Use local rebar, closes #515

2012-10-08 19:20:25 +02:00
607 changed files with 22587 additions and 146151 deletions
@@ -1 +0,0 @@
-lib/elixir/test/elixir/fixtures/*.txt text eol=lf
@@ -1,17 +1,13 @@
-/doc
-/ebin
+/.eunit/*
+/.full
 /lib/*/ebin/*
 /lib/*/tmp
+/lib/*/test/tmp
+/lib/elixir/src/elixir.app.src
 /lib/elixir/src/*_lexer.erl
 /lib/elixir/src/*_parser.erl
-/lib/elixir/src/elixir.app.src
 /lib/elixir/test/ebin
-/man/elixir.1
-/man/iex.1
+/deps/*
+/ebin
 /rel/elixir
-/Docs-v*.zip
-/Precompiled-v*.zip
-/.eunit
-/.release
-.elixir.plt
-erl_crash.dump
+erl_crash.dump
@@ -1,20 +1,9 @@
 language: erlang
-
-otp_release:
-  - 18.0
-  - 18.1
-  - 18.2
-  - 18.3
-  - 19.0
-  - 19.1
-
-sudo: false
-
-script: "make compile && rm -rf .git && make test"
-
+script: "make compile && make .full test"
 notifications:
  irc: "irc.freenode.org#elixir-lang"
  recipients:
    - jose.valim@plataformatec.com.br
-    - eric.meadows.jonsson@gmail.com
-
+otp_release:
+  - R15B01
+  - R15B
@@ -1,364 +1,53 @@
-# Changelog for Elixir v1.4
-
-Elixir v1.4 brings new features, enhancements and bug fixes into Elixir. The most notable changes are the addition of the `Registry` module and the `Task.async_stream/3` and `Task.async_stream/5` which aid developers in writing concurrent software. Those two features and a couple other improvements are described in detail below followed by the complete list of changes.
-
-## Registry
-
-The registry is a local, decentralized and scalable key-value process storage:
-
-  * Local because keys and values are only accessible to the current node (opposite to distributed)
-  * Decentralized because there is no single entity responsible for managing the registry
-  * Scalable because performance scales linearly with the addition of more cores upon partitioning
-
-A registry is chosen upon start to have unique or duplicate keys. Every key-value pair is associated to the process registering the key. Keys are automatically removed once the owner process terminates.
-
-    iex> Registry.start_link(:unique, MyRegistry)
-    iex> {:ok, _} = Registry.register(MyRegistry, "hello", 1)
-    iex> Registry.lookup(MyRegistry, "hello")
-    [{self(), 1}]
-
-With the registry, developers can provide dynamic process names, module-function dispatch or even a local pubsub system. See the `Registry` documentation for more information.
-
-## Syntax coloring
-
-Elixir v1.4 introduces the ability to syntax color inspected data structures:
-
-    iex> IO.puts inspect([hello: 1, world: "!"], syntax_colors: [atom: :cyan])
-    [hello: 1, world: "!"]
-
-Coloring is done with ANSI colors as specified in the `IO.ANSI` module.
-
-IEx automatically relies on this feature to provide syntax coloring for evaluated shell results. This behaviour can be configured via the `:syntax_colors` coloring option:
-
-    IEx.configure [colors: [syntax_colors: [atom: :cyan, string: :green]]]
-
-To disable coloring altogether, pass an empty list to `:syntax_colors`.
-
-## Calendar
-
-Elixir v1.3 introduced new calendar types. This release continues evolving the Calendar APIs by adding functions for comparing, adding and calculating the difference between types, retrieve the `day_of_week/1`, check if the current date is a `leap_year?/1` and more.
-
-## Task.async_stream
-
-When there is a need to traverse a collection of items concurrently, Elixir developers often resort to tasks:
-
-    collection
-    |> Enum.map(&Task.async(SomeMod, :function, [&1]))
-    |> Enum.map(&Task.await/1)
-
-While the snippet above works fine in many occasions, for large collections it will spawn and run concurrently as many tasks as there are items in the collection.
-
-`Task.async_stream/3` and `Task.async_stream/5` allows developers to process collections concurrently while controlling the maximum amount of concurrent tasks:
-
-    collection
-    |> Task.async_stream(SomeMod, :function, [], max_concurrency: System.schedulers_online)
-
-The `Task.async_stream` functions are also lazy, allowing developers to partially consume the stream until a condition is reached. Furthermore, `Task.Supervisor.async_stream/4` and `Task.Supervisor.async_stream/6` can be used to ensure the concurrent tasks are spawned under a given supervisor.
-
-## Application inference
-
-Mix v1.4 now automatically infers the list of applications that are required on runtime from your dependencies list.
-
-In previous Mix versions, most of your dependencies had to be added both to your dependencies list and applications list. Here is how a `mix.exs` would look like:
-
-    def application do
-      [applications: [:logger, :plug, :postgrex]]
-    end
-
-    def deps do
-      [{:plug, "~> 1.2"},
-       {:postgrex, "~> 1.0"}]
-    end
-
-This was error prone as many developers would not list their dependencies in their applications list.
-
-Mix v1.4 now automatically infers your applications list as long as you leave the `:applications` key empty. The `mix.exs` above can be rewritten to:
-
-    def application do
-      [extra_applications: [:logger]]
-    end
-
-    def deps do
-      [{:plug, "~> 1.2"},
-       {:postgrex, "~> 1.0"}]
-    end
-
-With the above, Mix will automatically build your application list based on your dependencies. Applications that are part of Erlang or Elixir that are required at runtime, such as `:logger`, must be added to the `:extra_applications` list. All extra applications will be included in the application list.
-
-Finally, if there is a dependency you don't want to include in the application runtime list, you can do so by specifying the `runtime: false` option:
-
-    {:distillery, "> 0.0.0", runtime: false}
-
-We hope this feature provides a more streamlined workflow for developers who are building releases for their Elixir projects.
-
-## Mix install from SCM
-
-Mix v1.4 can now install escripts and archives from both Git and Hex, providing you with even more options for distributing Elixir code.
-
-This makes it possible to distribute CLI applications written in Elixir by publishing a package which builds an escript to Hex. [`ex_doc`](https://hex.pm/packages/ex_doc) has been updated to serve as an example of how to use this new functionality.
-
-Simply running:
-
-    mix escript.install hex ex_doc
-
-will fetch `ex_doc` and its dependencies, build them, and then install `ex_doc` to `~/.mix/escripts` (by default). After adding `~/.mix/escripts` to your `PATH`, running `ex_doc` is as simple as:
-
-    ex_doc
-
-You can now also install archives from Hex in this way. Since they are fetched and built on the user's machine, they do not have the same limitations as pre-built archives. However, keep in mind archives run alongside every Mix project, which may lead to conflicts. For this reason, escripts is the preferred format.
-
-It is also possible to install escripts and archives by providing a Git/GitHub repo. See `mix help escript.install` and `mix help archive.install` for more details.
-
-## v1.4.5 (2017-06-22)
-
-This version includes changes that make Elixir fully compatible with Erlang/OTP 20.
-
-### 1. Enhancements
-
-#### Logger
-
-  * [Logger] Handle changes to crash reports in OTP 20
-
-### 2. Bug fixes
-
-#### Elixir
-
-  * [DateTime] Fix `DateTime.from_iso8601/2` when offset has no colon
-  * [Registry] Do not leak EXIT messages on `Registry.dispatch/3`
-
-## v1.4.4 (2017-05-15)
-
-This version includes changes that make Elixir fully compatible with Erlang/OTP 20-rc.1.
-
-### 1. Bug fixes
-
-#### Elixir
-
-  * [Map] Fix regression on struct update syntax
-
-## v1.4.3 (2017-05-15)
-
-This version includes changes that make Elixir fully compatible with Erlang/OTP 20-rc.1.
-
-### 1. Enhancements
-
-#### Elixir
-
-  * [Kernel] Improve compilation time for modules with many clauses
-  * [Map] Warn when attempting to override `__struct__` key
-  * [Regex] Add `recompile/1` and `recompile!/1` to ease transition to OTP 20 for archives and stored regexes
-
-#### Logger
-
-  * [Logger.Translator] Handle OTP 20 GenServer log messages
-
-#### Mix
-
-  * [mix compile] Recompile projects if OTP version changes
-
-### 2. Bug fixes
-
-#### Elixir
-
-  * [Kernel] Fix code generation when non-binary bitstrings are in AST
-  * [Record] Properly escape fields passed to `defrecord`
-  * [Version] Reject leading zeros according to the SemVer spec
-
-#### ExUnit
-
-  * [ExUnit.Diff] Do not fail when comparing maps with nil or boolean keys
-
-#### IEx
-
-  * [IEx.Helpers] Do not log exits on `IEx.Helpers.c/2` failures
-
-#### Mix
-
-  * [mix archive.install] Detect proper path on URLs with query strings
-  * [mix loadpaths] Do not assume all paths in loadpaths exist
-
-
-## v1.4.2 (2017-02-16)
-
-### 1. Bug fixes
-
-#### EEx
-
-  * [EEx] Support middle expressions on trim mode
-
-#### Elixir
-
-  * [Calendar] Correct typo on Calendar types
-  * [Kernel] Ensure redefined functions point to the proper source
-  * [OptionParser] Add `:allow_nonexistent_atoms` to support unsafe behaviour prior to v1.4
-  * [Stream] Allow consuming multiple items from suspended enumerable in `Stream.transform/3`
-  * [String] Incorporate new grapheme rules in Unicode 9
-
-#### IEx
-
-  * [IEx.Autocomplete] Do not crash on aliases which are not known at compile time
-
-#### Mix
-
-  * [Mix.Umbrella] Ensure umbrella projects can depend on other umbrella projects
-  * [Mix.Archive] Ensure previous archives with `.ez` extension are deleted
-
-## v1.4.1 (2017-01-26)
-
-### 1. Bug fixes
-
-#### Elixir
-
-  * [Kernel] Remove warning when making private functions overridable
-  * [Path] Ensure `Path.join/1` returns strings for lists of one element
-  * [Regex] Ensure `Regex.escape/1` also escapes `-`
-
-#### IEx
-
-  * [IEx] Disable ANSI detection for powershell to avoid false positives
-
-#### Mix
-
-  * [Mix.Make] Run `make clean` for `erlang.mk`
-  * [Mix.Rebar] Support all of rebar3 dependency package declaration
-  * [Mix.Rebar] Only pass overrides from parent to child in Rebar dep
-
-## v1.4.0 (2017-01-05)
-
-### 1. Enhancements
-
-#### Elixir
-
-  * [Calendar] Add `Date.compare/2`, `Time.compare/2`, `NaiveDateTime.compare/2` and `DateTime.compare/2`
-  * [Calendar] Support `NaiveDateTime.add/3` and `NaiveDateTime.diff/3` for adding seconds (up to microseconds) as well as the difference between two NaiveDateTimes in seconds (up to microseconds)
-  * [Calendar] Add `Date.leap_year?/1` and `Date.day_of_week/1`
-  * [Calendar] Ensure `Date`, `Time` and `NaiveDateTime` APIs work with any struct that provides the same set of fields as their respective struct. For example, a `NaiveDateTime` can be given to `Date` since it contains a superset of the fields in the `Date` struct
-  * [Calendar] Add `Time.utc_now/0` and `NaiveDateTime.utc_now/0`
-  * [Enum] Add `Enum.map_every/2` that invokes the given function with every nth item
-  * [Enum] Add `min/2`, `max/2`, `min_max/2`, `min_by/3`, `max_by/3`, and `min_max_by/3` that allow a function specifying the default value when the enumerable is empty
-  * [Enum] Introduce `Enum.zip/1` to zip multiple entries at once
-  * [Float] Introduce `Float.ratio/1` that returns a tuple with the numerator and denominator as integers to retrieve the given float
-  * [GenServer] Log warn on default `handle_info/2` implementation
-  * [Inspect] Support syntax coloring via the `:syntax_color` option
-  * [Integer] `Integer.digits/2` now accepts negative integers
-  * [Integer] Add `Integer.mod/2` and `Integer.floor_div/2`
-  * [IO] Add `:label` option to `IO.inspect/2` to help distinguish multiple `IO.inspect/2` calls.
-  * [Kernel] Recognize merge conflict markers in source and provide a readable error message
-  * [Kernel] Warn on unused module attributes
-  * [Kernel] Improve compiler message on unexpected end of line
-  * [Kernel] Raise `BadBooleanError` when a non-boolean is given on the left-hand side of `and`/`or`
-  * [List] Add `List.pop_at/3`
-  * [List] Add `List.myers_difference/2`
-  * [OptionParser] Expand multi-letter aliases in `OptionParser`
-  * [Process] Add `Process.send_after/4`
-  * [Process] Improve error messages on `Process.register/2` errors
-  * [Registry] Add a local, decentralized and scalable key-value process storage
-  * [Stream] Add `Stream.map_every/2` that invokes the given function with every nth item
-  * [Stream] Introduce `Stream.zip/1` to lazily zip multiple entries at once
-  * [String] Update to Unicode 9.0.0
-  * [Task] Add `Task.async_stream/3` and `Task.async_stream/5` as well as the supervised versions `Task.Supervisor.async_stream/4` and `Task.Supervisor.async_stream/6`
-  * [URI] Allow 0 as URI scheme default port
-
-#### ExUnit
-
-  * [ExUnit.Diff] Use red or green background for whitespace-only diffs
-  * [ExUnit.Doctest] Allow inspected structures with multiples lines and unicode characters in the doctest result
-  * [ExUnit.Formatter] Replace lhs/rhs with left/right in the formatter for clarity
-
-#### IEx
-
-  * [IEx.Autocomplete] Stop appending a trailing dot when autocompleting modules in IEx
-  * [IEx.Autocomplete] Support autocompletion for structs
-  * [IEx.Autocomplete] Improve IEx autocomplete to support navigating map atom keys
-  * [IEx.Helpers] `c/1` now compiles in memory by default to avoid common issue where `.beam` files remain at projects root directory
-  * [IEx.Helpers] Add info about protocols in `i/1`
-  * [IEx.Server] Support interrupting IEx evaluation through the Ctrl+G prompt
-
-#### Mix
-
-  * [mix archive] Compress archive files built by `mix archive` as they are now unzipped during installation
-  * [mix archive] Install from SCM
-  * [mix compile] Automatically infer the list of applications for Mix projects
-  * [mix cmd] Add the ability to specify one or more apps in `mix cmd`
-  * [mix deps] Warn if there are non-applications in the `apps` directory for umbrella projects
-  * [mix deps] Add warning for invalid paths on `mix deps.clean`
-  * [mix deps] Add `Mix.Project.apps_paths` that returns the paths to children applications in umbrella projects
-  * [mix deps] Add `MIX_REBAR` environment variable for overriding local rebar
-  * [mix escript] Install from SCM
-  * [mix new] Check directory existence in `mix new` and ask how to proceed if one exists
-  * [mix new] Applications built with the `--sup` flag now have an individual module to work as application callback
-  * [mix test] Add `--formatter` option to `mix test`
-  * [mix xref] Provide "did you mean?" suggestions for `mix xref`
-
-### 2. Bug fixes
-
-#### Elixir
-
-  * [Access] Do not accept nils in `Access.key/1` and `Access.key/2` in favor of explicit default values (or Access.key!/1 if you expect the key to always be available)
-  * [Float] Avoid multiple roundings in `Float.ceil/2`, `Float.floor/2` and `Float.round/2`
-  * [Kernel] Don't crash in `macro_exported?/3` when dealing with Erlang modules
-  * [Kernel] Ensure locals calls are rewritten when calling a local function or macro from inside a module
-  * [Kernel] Annotate the context for variables as zero-arity funs in quotes
-  * [Kernel.SpecialForms] Ensure comprehensions with guards and filters keep proper ordering,
-  * [Kernel.SpecialForms] Produce meaningful warning when with's else clauses have no effect
-  * [Macro] Wrap fn calls in parens in `Macro.to_string/2`
-  * [Macro] Do not print aliases as keys inside keyword lists in `Macro.to_string/2`
-  * [OptionParser] Support options in `OptionParser.to_argv/2` to ensure `:count` switches are correctly encoded
-  * [Stream] Ensure `Stream.take/2` does not consume next element on `:suspend`
-  * [String] Fix infinite recursion in `String.replace_leading/3` and `String.replace_trailing/3` when given an empty string
-  * [Task] Fix `Task.shutdown/1,2` infinite block when task has no monitor
-  * [Task] Ensure task cannot link after parents unlinks
-
-#### ExUnit
-
-  * [ExUnit] Fix a race condition in `assert_receive` where we would assert a message was not received but show it in the list of messages when the message is delivered right after the timeout value
-
-### IEx
-
-  * [IEx.Helpers] Purge consolidated protocols before and after `recompile/0`
-
-### Mix
-
-  * [Mix.Dep] Use `gmake` on FreeBSD instead of `make` when compiling make dependencies
-  * [Mix.Project] Only copy files from source when they're newer than destination (for Windows machines)
-  * [Mix.Task] Ensure non-recursive tasks inside umbrella are reenabled
-
-### 3. Soft deprecations (no warnings emitted)
-
-#### Elixir
-
-  * [Enum] `Enum.partition/2` has been deprecated in favor of `Enum.split_with/2`
-  * [System] Deprecate plural time units in favor of singular ones to align with future Erlang releases
-
-#### ExUnit
-
-  * [ExUnit] Using GenEvent to implement ExUnit formatters is deprecated. Please use the new `GenServer` based formatters instead
-
-### 4. Deprecations
-
-#### Elixir
-
-  * [Access] `Access.key/1` is deprecated due to erratic behaviour for missing keys, please use `Access.key/2` instead with proper default values
-  * [Behaviour] The `Behaviour` module is deprecated. Callbacks may now be defined directly via the `@callback` attribute
-  * [Enum] Deprecate `Enum.uniq/2` in favor of `Enum.uniq_by/2`
-  * [Float] `Float.to_char_list/2` and `Float.to_string/2` are deprecated (use the `:erlang.float_to_list/2` and `:erlang.float_to_binary/2` functions if such conversions are desired)
-  * [HashDict] The `HashDict` module is deprecated, in favour of the `Map`
-  * [HashSet] The `HashDict` module is deprecated, in favour of the `MapSet`  
-  * [Kernel] Deprecate support for making private functions overridable. Overridable functions must always be public as they must be contracts
-  * [Kernel] Anonymous functions with no expression after `->`, in favor of using an expression or returning `nil`
-  * [Kernel] Warn if variable is used as a function call
-  * [OptionParser] Deprecate aliases with multiple letters, such as `-abc`
-  * [Set] Deprecation of the `Set` module in favor of `MapSet`
-  * [Stream] Deprecate `Stream.uniq/2` in favor of `Stream.uniq_by/2`
-
-#### IEx
-
-  * [IEx.Helpers] `import_file/2` is deprecated in favor of `import_file_if_available/1`
-
-#### Mix
-
-  * [Mix.Utils] `underscore/1` and `camelize/1` are deprecated in favor of `Macro.underscore/1` and `Macro.camelize/1`
-
-## v1.3
-
-The CHANGELOG for v1.3 releases can be found [in the v1.3 branch](https://github.com/elixir-lang/elixir/blob/v1.3/CHANGELOG.md).
+# v0.6.0 (2012-08-01)
+
+* incompatible changes
+  * [Kernel] Compiled files now follow `Elixir-ModuleName` convention to solve issues with Erlang embedded mode. This removes the `__MAIN__` pseudo-variable as modules are now located inside `Elixir` namespace;
+  * [Kernel] `__using__` callback triggered by `use` now receives just one argument. Caller information can be accessed via macros using `__CALLER__`;
+  * [Module] Removed data functions in favor of unifying the attributes API;
+  * [Kernel] Comprehensions syntax changed to be more compatible with Erlang behavior;
+  * [Kernel] loop and recur were removed in favor of recursion with named functions;
+
+* deprecations
+  * [Access] The semantics of the access protocol were reduced from a broad query API to simple data structure key-based access;
+  * [Module] `Module.add_compile_callback(module, target, callback)` was deprecated in favor of `Module.add_attribute(module, :before_compile, { target, callback })`;
+  * [Module] `Module.function_defined?` was deprecated in favor of `Module.defines?`;
+  * [Module] `Module.defined_functions` was deprecated in favor of `Module.definitions_in`;
+  * [File] `File.read_info` was deprecated in favor of `File.stat`;
+  * [IO] `IO.print` was deprecated in favor of `IO.write`;
+  * [Kernel] Deprecated `__LINE__` and `__FUNCTION__` in favor of `__ENV__.line` and `__ENV__.function`;
+  * [Kernel] Deprecated `in_guard` in favor of `__CALLER__.in_guard?`;
+  * [Kernel] `refer` is deprecated in favor of `alias`;
+  * [ExUnit] Some assertions were deprecated in favor of simply using `assert()`; 
+
+* enhancements
+  * [OptionParser] Make OptionParser public, add support to flags and improved switch parsing;
+  * [Kernel] Operator `!` is now allowed in guard clauses;
+  * [IEx] IEx now provides autocomplete if the OS supports tty;
+  * [IEx] IEx now supports remsh;
+  * [Mix] First Mix public release;
+  * [Regex] Back references are now properly supported;
+  * [IEx] Elixir now defaults to compile with documentation and `d` can be used in IEx to print modules and functions documentation;
+  * [ExUnit] Support setup and teardown callbacks;
+  * [Kernel] Introduced operator `=~` for regular expression matches;
+  * [Kernel] Compiled docs now include the function signature;
+  * [Kernel] `defmodule` do not start a new variable scope, this improves meta-programming capabilities;
+  * [Range] Added a Range module with support to `in` operator (`x in 1..3`) and iterators;
+  * [Enum] Enhanced Enum protocol to support `Enum.count`;
+  * [Module] Added support to `@before_compile` and `@after_compile` callbacks. The first receives the module name while the latter receives the module name and its object code;
+  * [Kernel] quote special form now supports line and unquote as options;
+  * [Record] Allow `Record[_: value]` to set a default value to all records fields, as in Erlang;
+  * [IEx] Functions `c` and `m` are available in IEx to compile and print available module information. Functions `h` and `v` are available to show history and print previous commands values;
+  * [Enum] Optimized functions when a list is given as collection;
+  * [System] Added `System.find_executable`
+  * [Kernel] Document the macro `@` and allow attributes to be read inside functions;
+  * [IO/File] Many improvements to `File` and `IO` modules;
+  * [Macro] Added `Macro.expand`, useful for debugging what a macro expands to;
+  * [Enum] Added `find_index`;
+  * [Record] Records now provide a `to_keywords` function;
+  * [Kernel] Added support to the `%R` sigil. The same as `%r`, but without interpolation or escaping. Both implementations were also optimized to generate the regex at compilation time;
+  * [Kernel] Added `__ENV__` which returns a `Macro.Env` record with information about the compilation environment;
+  * [Kernel] Added `__CALLER__` inside macros which returns a `Macro.Env` record with information about the calling site;
+
+# v0.5.0 (2012-05-24)
+
+* First official release
@@ -1,56 +0,0 @@
-# Code of Conduct
-
-Contact: elixir-lang-conduct@googlegroups.com
-
-## Why have a Code of Conduct?
-
-As contributors and maintainers of this project, we are committed to providing a friendly, safe and welcoming environment for all, regardless of age, disability, gender, nationality, race, religion, sexuality, or similar personal characteristic.
-
-The goal of the Code of Conduct is to specify a baseline standard of behavior so that people with different social values and communication styles can talk about Elixir effectively, productively, and respectfully, even in face of disagreements. The Code of Conduct also provides a mechanism for resolving conflicts in the community when they arise.
-
-## Our Values
-
-These are the values Elixir developers should aspire to:
-
-  * Be friendly and welcoming
-  * Be patient
-    * Remember that people have varying communication styles and that not everyone is using their native language. (Meaning and tone can be lost in translation.)
-  * Be thoughtful
-    * Productive communication requires effort. Think about how your words will be interpreted.
-    * Remember that sometimes it is best to refrain entirely from commenting.
-  * Be respectful
-    * In particular, respect differences of opinion. It is important that we resolve disagreements and differing views constructively.
-  * Avoid destructive behavior
-    * Derailing: stay on topic; if you want to talk about something else, start a new conversation.
-    * Unconstructive criticism: don't merely decry the current state of affairs; offer (or at least solicit) suggestions as to how things may be improved.
-    * Snarking (pithy, unproductive, sniping comments).
-
-The following actions are explicitly forbidden:
-
-  * Insulting, demeaning, hateful, or threatening remarks.
-  * Discrimination based on age, disability, gender, nationality, race, religion, sexuality, or similar personal characteristic.
-  * Bullying or systematic harassment.
-  * Unwelcome sexual advances.
-  * Incitement to any of these.
-
-## Where does the Code of Conduct apply?
-
-If you participate in or contribute to the Elixir ecosystem in any way, you are encouraged to follow the Code of Conduct while doing so.
-
-Explicit enforcement of the Code of Conduct applies to the official mediums operated by the Elixir project:
-
-* The official GitHub projects and code reviews.
-* The official elixir-lang mailing lists.
-* The #elixir-lang IRC channel on Freenode.
-
-Other Elixir activities (such as conferences, meetups, and other unofficial forums) are encouraged to adopt this Code of Conduct. Such groups must provide their own contact information.
-
-Project maintainers may remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct.
-
-Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by emailing: elixir-lang-conduct@googlegroups.com. All complaints will be reviewed and investigated and will result in a response that is deemed necessary and appropriate to the circumstances. **All reports will be kept confidential**.
-
-**The goal of the Code of Conduct is to resolve conflicts in the most harmonious way possible**. We hope that in most cases issues may be resolved through polite discussion and mutual agreement. Bannings and other forceful measures are to be employed only as a last resort. **Do not** post about the issue publicly or try to rally sentiment against a particular individual or group.
-
-## Acknowledgements
-
-This document was based on the Code of Conduct from the Go project with parts derived from Django's Code of Conduct, Rust's Code of Conduct and the Contributor Covenant.
@@ -1,18 +0,0 @@
-### Precheck
-
-* Do not use the issues tracker for help or support (try Elixir Forum, Stack Overflow, IRC, etc.)
-* For proposing a new feature, please start a discussion on the Elixir Core mailing list
-* For bugs, do a quick search and make sure the bug has not yet been reported
-* Finally, be nice and have fun!
-
-### Environment
-
-* Elixir version (elixir -v):
-* Operating system:
-
-### Current behavior
-
-Include code samples, errors and stacktraces if appropriate.
-
-### Expected behavior
-
@@ -0,0 +1,10 @@
+LEGAL NOTICE INFORMATION
+------------------------
+
+All the files in this distribution are covered under either Elixir's
+license (see the file LICENSE) except the files mentioned below that
+contains sections that are under Erlang's License (EPL):
+
+lib/elixir/src/elixir_glob.erl
+lib/elixir/src/elixir_parser.erl (generated by build scripts)
+
@@ -1,4 +1,4 @@
-Copyright 2012 Plataformatec
+Copyright 2012 Plataformatec.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
@@ -1,259 +1,103 @@
-REBAR ?= "$(CURDIR)/rebar"
-PREFIX ?= /usr/local
-SHARE_PREFIX ?= $(PREFIX)/share
-CANONICAL :=
-ELIXIRC := bin/elixirc --verbose --ignore-module-conflict
-ERLC := erlc -I lib/elixir/include
-ERL := erl -I lib/elixir/include -noshell -pa lib/elixir/ebin
-VERSION := $(strip $(shell cat VERSION))
-Q := @
-LIBDIR := lib
-BINDIR := bin
-INSTALL = install
-INSTALL_DIR = $(INSTALL) -m755 -d
-INSTALL_DATA = $(INSTALL) -m644
-INSTALL_PROGRAM = $(INSTALL) -m755
-GIT_REVISION = $(strip $(shell git rev-parse HEAD 2> /dev/null ))
-GIT_TAG = $(strip $(shell head="$(call GIT_REVISION)"; git tag --points-at $$head 2> /dev/null | tail -1) )
+REBAR:=$(shell echo `pwd`/rebar)
+ELIXIRC:=bin/elixirc --ignore-module-conflict $(ELIXIRC_OPTS)
+ERLC:=erlc -I lib/elixir/include
+ERL:=erl -I lib/elixir/include -noshell -env ERL_LIBS $ERL_LIBS:lib
+FULLFLAG:=.full
+VERSION:=0.6.0

-.PHONY: install compile erlang elixir build_plt clean_plt dialyze test clean install_man clean_man docs Docs.zip Precompiled.zip zips
+.PHONY: 1
 .NOTPARALLEL: compile

-#==> Functions
+#==> Templates
+define TASK_TEMPLATE
+$(1): lib/$(1)/ebin/Elixir-$(2).beam lib/$(1)/ebin/$(1).app

-define CHECK_ERLANG_RELEASE
-	$(Q) erl -noshell -eval '{V,_} = string:to_integer(erlang:system_info(otp_release)), io:fwrite("~s", [is_integer(V) and (V >= 18)])' -s erlang halt | grep -q '^true'; \
-		if [ $$? != 0 ]; then \
-		   echo "At least Erlang 18.0 is required to build Elixir"; \
-		   exit 1; \
-		fi;
-endef
+lib/$(1)/ebin/$(1).app:
+	@ cd lib/$(1) && ../../bin/elixir ../../bin/mix compile.app

-define APP_TEMPLATE
-$(1): lib/$(1)/ebin/Elixir.$(2).beam lib/$(1)/ebin/$(1).app
-
-lib/$(1)/ebin/$(1).app: lib/$(1)/mix.exs
-	$(Q) mkdir -p lib/$(1)/_build/shared/lib/$(1)
-	$(Q) cp -R lib/$(1)/ebin lib/$(1)/_build/shared/lib/$(1)/
-	$(Q) cd lib/$(1) && ../../bin/elixir -e 'Mix.start(:permanent, [])' -r mix.exs -e 'Mix.Task.run("compile.app")'
-	$(Q) cp lib/$(1)/_build/shared/lib/$(1)/ebin/$(1).app lib/$(1)/ebin/$(1).app
-	$(Q) rm -rf lib/$(1)/_build
-
-lib/$(1)/ebin/Elixir.$(2).beam: $(wildcard lib/$(1)/lib/*.ex) $(wildcard lib/$(1)/lib/*/*.ex) $(wildcard lib/$(1)/lib/*/*/*.ex)
+lib/$(1)/ebin/Elixir-$(2).beam: $(wildcard lib/$(1)/lib/*.ex) $(wildcard lib/$(1)/lib/*/*.ex) $(wildcard lib/$(1)/lib/*/*/*.ex) $$(FORCE)
 	@ echo "==> $(1) (compile)"
-	@ rm -rf lib/$(1)/ebin
-	$(Q) cd lib/$(1) && ../../$$(ELIXIRC) "lib/**/*.ex" -o ebin
+	@ $$(ELIXIRC) "lib/$(1)/lib/**/*.ex" -o lib/$(1)/ebin

-test_$(1): compile $(1)
+test_$(1): $(1)
 	@ echo "==> $(1) (exunit)"
-	$(Q) cd lib/$(1) && ../../bin/elixir -r "test/test_helper.exs" -pr "test/**/*_test.exs";
+	@ cd lib/$(1) && time ../../bin/elixir -r "test/test_helper.exs" -pr "test/**/*_test.exs"
 endef

 #==> Compilation tasks
-
-KERNEL:=lib/elixir/ebin/Elixir.Kernel.beam
-UNICODE:=lib/elixir/ebin/Elixir.String.Unicode.beam
-
-default: compile
+KERNEL:=lib/elixir/ebin/Elixir-Kernel.beam

 compile: lib/elixir/src/elixir.app.src erlang elixir

 lib/elixir/src/elixir.app.src: src/elixir.app.src
-	$(Q) $(call CHECK_ERLANG_RELEASE)
-	$(Q) rm -rf lib/elixir/src/elixir.app.src
-	$(Q) echo "%% This file is automatically generated from <project_root>/src/elixir.app.src" \
-	                             >lib/elixir/src/elixir.app.src
-	$(Q) cat src/elixir.app.src >>lib/elixir/src/elixir.app.src
+	@ rm -rf lib/elixir/src/elixir.app.src
+	@ cp src/elixir.app.src lib/elixir/src/elixir.app.src

 erlang:
-	$(Q) cd lib/elixir && $(REBAR) compile
+	@ cd lib/elixir && $(REBAR) compile

-# Since Mix depends on EEx and EEx depends on
-# Mix, we first compile EEx without the .app
-# file, then mix and then compile EEx fully
-elixir: stdlib lib/eex/ebin/Elixir.EEx.beam mix ex_unit logger eex iex
+# We need to compile only EEx (without the app)
+# file so we can compile Mix
+elixir: kernel lib/eex/ebin/Elixir-EEx.beam mix ex_unit eex

-stdlib: $(KERNEL) VERSION
-$(KERNEL): lib/elixir/lib/*.ex lib/elixir/lib/*/*.ex lib/elixir/lib/*/*/*.ex
-	$(Q) if [ ! -f $(KERNEL) ]; then                  \
-		echo "==> bootstrap (compile)";                 \
-		$(ERL) -s elixir_compiler core -s erlang halt;  \
+kernel: $(KERNEL)
+$(KERNEL): lib/elixir/lib/*.ex lib/elixir/lib/*/*.ex $(FORCE)
+	@ if [ -f $(KERNEL) ]; then                                 \
+		echo "==> kernel (compile)";                            \
+		$(ELIXIRC) "lib/elixir/lib/**/*.ex" -o lib/elixir/ebin; \
+	else                                                        \
+		echo "==> bootstrap (compile)";                         \
+		$(ERL) -s elixir_compiler core -s erlang halt;          \
 	fi
-	@ echo "==> elixir (compile)";
-	$(Q) cd lib/elixir && ../../$(ELIXIRC) "lib/kernel.ex" -o ebin;
-	$(Q) cd lib/elixir && ../../$(ELIXIRC) "lib/**/*.ex" -o ebin;
-	$(Q) $(MAKE) unicode
-	$(Q) rm -rf lib/elixir/ebin/elixir.app
-	$(Q) cd lib/elixir && $(REBAR) compile
+	@ rm -rf lib/elixir/ebin/elixir.app
+	@ cd lib/elixir && $(REBAR) compile

-unicode: $(UNICODE)
-$(UNICODE): lib/elixir/unicode/*
-	@ echo "==> unicode (compile)";
-	$(Q) cd lib/elixir && ../../$(ELIXIRC) unicode/unicode.ex -o ebin;
-
-$(eval $(call APP_TEMPLATE,ex_unit,ExUnit))
-$(eval $(call APP_TEMPLATE,logger,Logger))
-$(eval $(call APP_TEMPLATE,eex,EEx))
-$(eval $(call APP_TEMPLATE,mix,Mix))
-$(eval $(call APP_TEMPLATE,iex,IEx))
-
-install: compile
-	@ echo "==> elixir (install)"
-	$(Q) for dir in lib/*; do \
-		rm -Rf $(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin; \
-		$(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin"; \
-		$(INSTALL_DATA) $$dir/ebin/* "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin"; \
-	done
-	$(Q) $(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/bin"
-	$(Q) $(INSTALL_PROGRAM) $(filter-out %.ps1, $(filter-out %.bat, $(wildcard bin/*))) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/bin"
-	$(Q) $(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(BINDIR)"
-	$(Q) for file in "$(DESTDIR)$(PREFIX)"/$(LIBDIR)/elixir/bin/* ; do \
-		ln -sf "../$(LIBDIR)/elixir/bin/$${file##*/}" "$(DESTDIR)$(PREFIX)/$(BINDIR)/" ; \
-	done
-	$(MAKE) install_man
+$(eval $(call TASK_TEMPLATE,ex_unit,ExUnit))
+$(eval $(call TASK_TEMPLATE,eex,EEx))
+$(eval $(call TASK_TEMPLATE,mix,Mix))

 clean:
-	cd lib/elixir && $(REBAR) clean
+	@ rm -rf .full
+	@ rm -rf lib/*/ebin
+	@ cd lib/elixir && $(REBAR) clean
+
+#==> Release tasks
+$(FULLFLAG): $(wildcard lib/*/ebin/*)
+	make ELIXIRC_OPTS="--debug-info" FORCE=1
+	touch $(FULLFLAG)
+
+zip: $(FULLFLAG)
+	rm -rf v$(VERSION).zip
+	zip -9 -r v$(VERSION).zip bin CHANGELOG.md LEGAL lib/*/ebin LICENSE README.md rel
+
+docs: $(FULLFLAG)
+	mkdir -p ebin
+	rm -rf docs
+	cp -R -f lib/*/ebin/*.beam ./ebin
+	bin/elixir ../exdoc/bin/exdoc
 	rm -rf ebin
-	rm -rf lib/*/ebin
-	rm -rf lib/elixir/test/ebin
-	rm -rf lib/*/tmp
-	rm -rf lib/mix/test/fixtures/git_repo
-	rm -rf lib/mix/test/fixtures/deps_on_git_repo
-	rm -rf lib/mix/test/fixtures/git_rebar
-	rm -rf lib/elixir/src/elixir.app.src
-	$(MAKE) clean_man

-clean_exbeam:
-	$(Q) rm -f lib/*/ebin/Elixir.*.beam
+release_docs: docs
+	cd ../elixir-lang.github.com && git checkout master
+	rm -rf ../elixir-lang.github.com/docs/master
+	mv output ../elixir-lang.github.com/docs/master

-#==> Create Documentation
-
-LOGO_PATH = $(shell test -f ../docs/logo.png && echo "--logo ../docs/logo.png")
-SOURCE_REF = $(shell tag="$(call GIT_TAG)" revision="$(call GIT_REVISION)"; echo "$${tag:-$$revision}\c")
-DOCS_FORMAT = html
-COMPILE_DOCS = bin/elixir ../ex_doc/bin/ex_doc "$(1)" "$(VERSION)" "lib/$(2)/ebin" -m "$(3)" -u "https://github.com/elixir-lang/elixir" --source-ref "$(call SOURCE_REF)" $(call LOGO_PATH) -o doc/$(2) -n https://hexdocs.pm/$(2)/$(CANONICAL) -p http://elixir-lang.org/docs.html -f "$(DOCS_FORMAT)" $(4)
-
-docs: compile ../ex_doc/bin/ex_doc docs_elixir docs_eex docs_mix docs_iex docs_ex_unit docs_logger
-
-docs_elixir: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (elixir)"
-	$(Q) rm -rf doc/elixir
-	$(call COMPILE_DOCS,Elixir,elixir,Kernel,-e "lib/elixir/pages/Behaviours.md" -e "lib/elixir/pages/Guards.md" -e "lib/elixir/pages/Naming Conventions.md" -e "lib/elixir/pages/Operators.md" -e "lib/elixir/pages/Typespecs.md" -e "lib/elixir/pages/Writing Documentation.md")
-
-docs_eex: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (eex)"
-	$(Q) rm -rf doc/eex
-	$(call COMPILE_DOCS,EEx,eex,EEx)
-
-docs_mix: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (mix)"
-	$(Q) rm -rf doc/mix
-	$(call COMPILE_DOCS,Mix,mix,Mix)
-
-docs_iex: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (iex)"
-	$(Q) rm -rf doc/iex
-	$(call COMPILE_DOCS,IEx,iex,IEx)
-
-docs_ex_unit: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (ex_unit)"
-	$(Q) rm -rf doc/ex_unit
-	$(call COMPILE_DOCS,ExUnit,ex_unit,ExUnit)
-
-docs_logger: compile ../ex_doc/bin/ex_doc
-	@ echo "==> ex_doc (logger)"
-	$(Q) rm -rf doc/logger
-	$(call COMPILE_DOCS,Logger,logger,Logger)
-
-../ex_doc/bin/ex_doc:
-	@ echo "ex_doc is not found in ../ex_doc as expected. See README for more information."
-	@ false
-
-#==> Zips
-
-Docs.zip: docs
-	rm -rf Docs-v$(VERSION).zip
-	zip -9 -r Docs-v$(VERSION).zip CHANGELOG.md doc NOTICE LICENSE README.md
-	@ echo "Docs file created $(CURDIR)/Docs-v$(VERSION).zip"
-
-Precompiled.zip: build_man compile
-	rm -rf Precompiled-v$(VERSION).zip
-	zip -9 -r Precompiled-v$(VERSION).zip bin CHANGELOG.md lib/*/ebin LICENSE man NOTICE README.md VERSION
-	@ echo "Precompiled file created $(CURDIR)/Precompiled-v$(VERSION).zip"
-
-zips: Precompiled.zip Docs.zip
+release_erl: $(FULLFLAG)
+	@ rm -rf rel/elixir
+	@ cd rel && ../rebar generate

 #==> Tests tasks
-
 test: test_erlang test_elixir

-TEST_ERL = lib/elixir/test/erlang
-TEST_EBIN = lib/elixir/test/ebin
-TEST_ERLS = $(addprefix $(TEST_EBIN)/, $(addsuffix .beam, $(basename $(notdir $(wildcard $(TEST_ERL)/*.erl)))))
-
-test_erlang: compile $(TEST_ERLS)
+test_erlang: compile
 	@ echo "==> elixir (eunit)"
-	$(Q) $(ERL) -pa $(TEST_EBIN) -s test_helper test;
-	@ echo ""
+	@ mkdir -p lib/elixir/test/ebin
+	@ $(ERLC) -pa lib/elixir/ebin -o lib/elixir/test/ebin lib/elixir/test/erlang/*.erl
+	@ time $(ERL) -pa lib/elixir/test/ebin -s test_helper test -s erlang halt
+	@ echo

-$(TEST_EBIN)/%.beam: $(TEST_ERL)/%.erl
-	$(Q) mkdir -p $(TEST_EBIN)
-	$(Q) $(ERLC) -o $(TEST_EBIN) $<
+test_elixir: test_kernel test_mix test_ex_unit test_eex

-test_elixir: test_stdlib test_ex_unit test_logger test_mix test_eex test_iex
-
-test_stdlib: compile
-	@ echo "==> elixir (exunit)"
-	$(Q) exec epmd & exit
-	$(Q) if [ "$(OS)" = "Windows_NT" ]; then \
-		cd lib/elixir && cmd //C call ../../bin/elixir.bat -r "test/elixir/test_helper.exs" -pr "test/elixir/**/*_test.exs"; \
-	else \
-		cd lib/elixir && ../../bin/elixir -r "test/elixir/test_helper.exs" -pr "test/elixir/**/*_test.exs"; \
-	fi
-
-#==> Dialyzer tasks
-
-DIALYZER_OPTS = --no_check_plt --fullpath -Werror_handling -Wunmatched_returns -Wunderspecs
-PLT = .elixir.plt
-
-$(PLT):
-	@ echo "==> Building PLT with Elixir's dependencies..."
-	$(Q) dialyzer --output_plt $(PLT) --build_plt --apps erts kernel stdlib compiler syntax_tools parsetools tools ssl inets
-
-clean_plt:
-	$(Q) rm -f $(PLT)
-
-build_plt: clean_plt $(PLT)
-
-dialyze: compile $(PLT)
-	@ echo "==> Dialyzing Elixir..."
-	$(Q) dialyzer --plt $(PLT) $(DIALYZER_OPTS) lib/*/ebin
-
-#==> Man page tasks
-
-build_man: man/iex.1 man/elixir.1
-
-man/iex.1:
-	$(Q) cp man/iex.1.in man/iex.1
-	$(Q) sed -i.bak "/{COMMON}/r common" man/iex.1
-	$(Q) sed -i.bak "/{COMMON}/d" man/iex.1
-	$(Q) rm man/iex.1.bak
-
-man/elixir.1:
-	$(Q) cp man/elixir.1.in man/elixir.1
-	$(Q) sed -i.bak "/{COMMON}/r common" man/elixir.1
-	$(Q) sed -i.bak "/{COMMON}/d" man/elixir.1
-	$(Q) rm man/elixir.1.bak
-
-clean_man:
-	rm -f man/elixir.1
-	rm -f man/iex.1
-
-install_man: build_man
-	$(Q) mkdir -p $(DESTDIR)$(SHARE_PREFIX)/man/man1
-	$(Q) $(INSTALL_DATA) man/elixir.1  $(DESTDIR)$(SHARE_PREFIX)/man/man1
-	$(Q) $(INSTALL_DATA) man/elixirc.1 $(DESTDIR)$(SHARE_PREFIX)/man/man1
-	$(Q) $(INSTALL_DATA) man/iex.1     $(DESTDIR)$(SHARE_PREFIX)/man/man1
-	$(Q) $(INSTALL_DATA) man/mix.1     $(DESTDIR)$(SHARE_PREFIX)/man/man1
-	$(MAKE) clean_man
+test_kernel: compile
+	@ echo "==> kernel (exunit)"
+	@ cd lib/elixir && time ../../bin/elixir -r "test/elixir/test_helper.exs" -pr "test/elixir/**/*_test.exs"
@@ -1,22 +0,0 @@
-LEGAL NOTICE INFORMATION
------------------------
-
-All the files in this distribution are copyright (c) 2012 Plataformatec
-covered under Elixir's license (see the file LICENSE) except the cases
-below.
-
-== lib/elixir/src/elixir_parser.erl (generated by build scripts)
-
-Copyright Ericsson AB 1996-2015
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
@@ -1,155 +1,52 @@
 ![Elixir](https://github.com/elixir-lang/elixir-lang.github.com/raw/master/images/logo/logo.png)
 =========
-[![Build Status](https://secure.travis-ci.org/elixir-lang/elixir.svg?branch=master
-"Build Status")](https://travis-ci.org/elixir-lang/elixir)
+[![Build Status](https://secure.travis-ci.org/elixir-lang/elixir.png?branch=master "Build Status")](http://travis-ci.org/elixir-lang/elixir)

-For more about Elixir, installation and documentation,
-[check Elixir's website](http://elixir-lang.org/).
+For more about Elixir, installation and documentation, [check Elixir's website](http://elixir-lang.org/).

-## Compiling from source
+# Usage

-To run Elixir from source, clone this repository to your machine, compile and test it:
+If you want to contribute to Elixir or run it from source, clone this repository to your machine, compile and test it:

-```sh
-git clone https://github.com/elixir-lang/elixir.git
-cd elixir
-make clean test
-```
+    $ git clone https://github.com/elixir-lang/elixir.git
+    $ cd elixir
+    $ make test

-> Note: if you are running on Windows,
-[this article includes important notes for compiling Elixir from source
-on Windows](https://github.com/elixir-lang/elixir/wiki/Windows).
+If tests pass, you are ready to move on to the [Getting Started guide][1] or to try Interactive Elixir by running: `bin/iex` in your terminal.

-If Elixir fails to build (specifically when pulling in a new version via
-`git`), be sure to remove any previous build artifacts by running
-`make clean`, then `make test`.
+However, if tests fail, it is likely you have an outdated Erlang version (Elixir requires Erlang R15B or later). You can check your Erlang version by calling `erl` in the command line. You will see some information as follow:

-If tests pass, you are ready to move on to the [Getting Started guide][1]
-or to try Interactive Elixir by running `bin/iex` in your terminal.
+    Erlang R15B (erts-5.8.4) [source] [64-bit] [smp:2:2] [rq:2] [async-threads:0] [hipe] [kernel-poll:false]

-However, if tests fail, it is likely you have an outdated Erlang version
-(Elixir requires Erlang 18.0 or later). You can check your Erlang version
-by calling `erl` in the command line. You will see some information as follows:
+If you have the correct version and tests still fail, feel free to [open an issue][2].

-    Erlang/OTP 18 [erts-7.0] [source] [smp:2:2] [async-threads:10] [hipe] [kernel-poll:false]
+# Contributing

-If you have properly set up your dependencies and tests still fail,
-you may want to open up a bug report, as explained next.
+If you want to contribute, Elixir code is divided in applications inside the `lib` folder:

-## Bug reports
+* `elixir` - Contains Elixir's kernel and stdlib;

-For reporting bugs, [visit our issues tracker][2] and follow the steps
-for reporting a new issue. Please disclose security vulnerabilities
-privately at elixir-security@googlegroups.com.
+* `eex` - Template engine that allows you to embed Elixir;

-## Contributing
+* `ex_unit` - Simple test framework that ships with Elixir;

-We welcome everyone to contribute to Elixir and help us tackle existing issues!
-To do so, there are a few things you need to know about the code. First, Elixir
-code is divided in applications inside the `lib` folder:
+We usually keep a list of features and bugs [in the issue tracker][2].

-* `elixir` - Contains Elixir's kernel and stdlib
+# Important links

-* `eex` - Template engine that allows you to embed Elixir
-
-* `ex_unit` - Simple test framework that ships with Elixir
-
-* `iex` - IEx, Elixir's interactive shell
-
-* `logger` - The built-in logger
-
-* `mix` - Elixir's build tool
-
-You can run all tests in the root directory with `make test` and you can
-also run tests for a specific framework `make test_#{NAME}`, for example,
-`make test_ex_unit`.
-
-In case you are changing a single file, you can compile and run tests only
-for that particular file for fast development cycles. For example, if you
-are changing the String module, you can compile it and run its tests as:
-
-```sh
-bin/elixirc lib/elixir/lib/string.ex -o lib/elixir/ebin
-bin/elixir lib/elixir/test/elixir/string_test.exs
-```
-
-After your changes are done, please remember to run the full suite with
-`make test`.
-
-From time to time, your tests may fail in an existing Elixir checkout and
-may require a clean start by running `make clean compile`. You can always
-check [the official build status on Travis-CI](https://travis-ci.org/elixir-lang/elixir).
-
-With tests running and passing, you are ready to contribute to Elixir and
-[send a pull request](https://help.github.com/articles/using-pull-requests/).
-We have saved some excellent pull requests we have received in the past in
-case you are looking for some examples:
-
-* [Implement Enum.member? – Pull Request](https://github.com/elixir-lang/elixir/pull/992)
-* [Add String.valid? – Pull Request](https://github.com/elixir-lang/elixir/pull/1058)
-* [Implement capture_io for ExUnit – Pull Request](https://github.com/elixir-lang/elixir/pull/1059)
-
-We usually keep a list of enhancements and bugs [in the issue tracker][2].
-For proposing new features, please start a discussion in the
-[Elixir Core mailing list][3]. Keep in mind that it is your responsibility
-to argue and explain why a feature is useful and how it will impact the
-codebase and the community. Finally, remember all interactions in our official
-spaces follow our [Code of Conduct][7].
-
-### Reviewing changes
-
-Once a pull request is sent, the Elixir team will review your changes.
-We outline our process below to clarify the roles of everyone involved.
-
-All pull requests must be approved by two committers before being merged into
-the repository. In case any changes are necessary, the team will leave
-appropriate comments requesting changes to the code.
-
-The Elixir team may optionally assign someone to review a pull request.
-In case someone is assigned, they must explicitly approve the code before
-another team member can merge it.
-
-When review is completed, your pull request will be squashed and merged
-into the repository.
-
-## Building documentation
-
-Building the documentation requires [ExDoc](https://github.com/elixir-lang/ex_doc)
-to be installed and built alongside Elixir:
-
-```sh
-# After cloning and compiling Elixir, in its parent directory:
-git clone git://github.com/elixir-lang/ex_doc.git
-cd ex_doc && ../elixir/bin/mix do deps.get, compile
-cd ../elixir && make docs
-```
-
-This will produce documentation sets for `elixir`, `mix`, etc., under
-the `doc` directory. If you are planning to contribute documentation,
-[please check our best practices for writing documentation](http://elixir-lang.org/docs/stable/elixir/writing-documentation.html).
-
-## Development links
-
-  * [Elixir Website][1]
-  * [Elixir Documentation][6]
-  * [Elixir Core Mailing list (development)][3]
-  * [Issues tracker][2]
-  * [Code of Conduct][7]
-  * **[#elixir-lang][4]** on [Freenode][5] IRC
+* #elixir-lang on freenode IRC
+* [Website][1]
+* [Issue tracker][2]
+* [Mailing list][3]

  [1]: http://elixir-lang.org
  [2]: https://github.com/elixir-lang/elixir/issues
-  [3]: https://groups.google.com/group/elixir-lang-core
-  [4]: https://webchat.freenode.net/?channels=#elixir-lang
-  [5]: http://www.freenode.net
-  [6]: http://elixir-lang.org/docs.html
-  [7]: CODE_OF_CONDUCT.md
+  [3]: http://groups.google.com/group/elixir-lang-core

-## License
+# License

 "Elixir" and the Elixir logo are copyright (c) 2012 Plataformatec.

-Elixir source code is released under Apache 2 License.
+Elixir source code is released under Apache 2 License with some parts under Erlang's license (EPL).

-Check [NOTICE](NOTICE) and [LICENSE](LICENSE) files for more
-information.
+Check LEGAL and LICENSE files for more information.
@@ -1,43 +1,25 @@
-# Release process
-
-## All releases
+## Release process

 This document simply outlines the release process:

-1. Ensure you are running on the oldest supported Erlang version
+1) Remove .dev extension from current versions

-2. Remove all `-dev` extension from versions (see below for all files)
+2) Run `make clean test` to ensure all tests pass from scratch

-3. Ensure CHANGELOG is updated and add current date
+3) Ensure CHANGELOG is updated and tag release version with timestamp in it

-4. Commit changes above with title "Release vVERSION" and generate new tag
+4) Commit changes above and tag new version on Git

-5. Run `make clean test` to ensure all tests pass from scratch and the CI is green
+5) Release new docs, update elixir-lang.org

-6. Recompile an existing project (for example, Ecto) to ensure manifests can be upgraded
+6) Push new zip to Elixir's downloads page

-7. Push branch and the new tag
-
-8. If a new `vMAJOR.MINOR`, create a new branch "vMAJOR.MINOR" and set `CANONICAL=` in Makefile before building docs
-
-9. Publish new zips with `make zips`, upload `Precompiled.zip` and `Docs.zip` to GitHub Releases
-
-10. Add the release to `elixir.csv` and `_data/elixir-versions.yml` files in `elixir-lang/elixir-lang.github.com`
-
-11. After a new `vMAJOR.MINOR`, move back to master, bump versions, start new CHANGELOG, add `-dev` back and commit "Start vMAJOR.MINOR+1"
+7) After release, bump versions and add .dev back

 ## Places where version is mentioned

-* VERSION
-* CHANGELOG.md
-* src/elixir.app.src (not lib/elixir/src/elixir.app.src)
-
-## Deprecation policy
-
-Elixir deprecations happens in 3 steps:
-
-  1. The feature is soft-deprecated. It means both CHANGELOG and documentation must list the feature as deprecated but no warning is effectively emitted by running the code. There is no requirement to soft-deprecate a feature.
-
-  2. The feature is effectively deprecated by emitting warnings on usage. In order to deprecate a feature, the proposed alternative MUST exist for AT LEAST two versions. For example, `Enum.uniq/2` was soft-deprecated in favor of `Enum.uniq_by/2` in Elixir v1.1. This means a deprecation warning may only be emitted by Elixir v1.3 or later.
-
-  3. The feature is removed. This can only happen on major releases. This means deprecated features in Elixir v1.x shall only be removed by Elixir v2.x.
+* src/elixir.app.src
+* lib/elixir/lib/system.ex
+* rel/reltool.config
+* Makefile
+* CHANGELOG
@@ -1 +0,0 @@
-1.4.5
@@ -1,36 +1,29 @@
 #!/bin/sh
-if [ $# -eq 0 ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
+if [ $# -eq 0 ]; then
  echo "Usage: `basename $0` [options] [.exs file] [data]

-  -v                          Prints version and exits
-  -e COMMAND                  Evaluates the given command (*)
-  -r FILE                     Requires the given files/patterns (*)
-  -S SCRIPT                   Finds and executes the given script in PATH
-  -pr FILE                    Requires the given files/patterns in parallel (*)
-  -pa PATH                    Prepends the given path to Erlang code path (*)
-  -pz PATH                    Appends the given path to Erlang code path (*)
-
-  --app APP                   Starts the given app and its dependencies (*)
-  --cookie COOKIE             Sets a cookie for this distributed node
-  --detached                  Starts the Erlang VM detached from console
-  --erl SWITCHES              Switches to be passed down to Erlang (*)
-  --hidden                    Makes a hidden node
-  --logger-otp-reports BOOL   Enables or disables OTP reporting
-  --logger-sasl-reports BOOL  Enables or disables SASL reporting
-  --name NAME                 Makes and assigns a name to the distributed node
-  --no-halt                   Does not halt the Erlang VM after execution
-  --sname NAME                Makes and assigns a short name to the distributed node
-  --werl                      Uses Erlang's Windows shell GUI (Windows only)
+  -v                Prints version and exit
+  -e \"command\"      Evaluates the given command (*)
+  -r \"file\"         Requires the given files/patterns (*)
+  -S \"script\"       Finds and executes the given script (*)
+  -pr \"file\"        Requires the given files/patterns in parallel (*)
+  -pa \"path\"        Prepends the given path to Erlang code path (*)
+  -pz \"path\"        Appends the given path to Erlang code path (*)
+  --erl \"switches\"  Switches to be passed down to erlang
+  --name \"name\"     Makes and assigns a name to the distributed node
+  --sname \"name\"    Makes and assigns a short name to the distributed node
+  --remsh \"name\"    Connects to a node using a remote shell (with iex)
+  --no-halt         Does not halt the Erlang VM after execution

 ** Options marked with (*) can be given more than once
 ** Options given after the .exs file or -- are passed down to the executed code
-** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS or --erl" >&2
+** Options can be passed to the erlang runtime using ELIXIR_ERL_OPTS or --erl" >&2
  exit 1
 fi

 readlink_f () {
  cd "$(dirname "$1")" > /dev/null
-  filename="$(basename "$1")"
+  local filename="$(basename "$1")"
  if [ -h "$filename" ]; then
    readlink_f "$(readlink "$filename")"
  else
@@ -38,8 +31,6 @@ readlink_f () {
  fi
 }

-MODE="elixir"
-ERL_EXEC="erl"
 ERL=""
 I=1

@@ -47,52 +38,21 @@ while [ $I -le $# ]; do
  S=1
  eval "PEEK=\${$I}"
  case "$PEEK" in
-    +iex)
-        MODE="iex"
-        ;;
-    +elixirc)
-        MODE="elixirc"
-        ;;
    -v|--compile|--no-halt)
        ;;
-    -e|-r|-pr|-pa|-pz|--remsh|--app)
+    -e|-r|-pr|-pa|-pz|--remsh|-S)
        S=2
        ;;
-    --detached|--hidden)
-        ERL="$ERL `echo $PEEK | cut -c 2-`"
-        ;;
-    --cookie)
-        I=$(expr $I + 1)
-        eval "VAL=\${$I}"
-        ERL="$ERL -setcookie "$VAL""
-        ;;
    --sname|--name)
        I=$(expr $I + 1)
        eval "VAL=\${$I}"
        ERL="$ERL `echo $PEEK | cut -c 2-` "$VAL""
        ;;
-    --logger-otp-reports)
-        I=$(expr $I + 1)
-        eval "VAL=\${$I}"
-        if [ "$VAL" == 'true' ] || [ "$VAL" == 'false' ]; then
-            ERL="$ERL -logger handle_otp_reports "$VAL""
-        fi
-        ;;
-    --logger-sasl-reports)
-        I=$(expr $I + 1)
-        eval "VAL=\${$I}"
-        if [ "$VAL" == 'true' ] || [ "$VAL" == 'false' ]; then
-            ERL="$ERL -logger handle_sasl_reports "$VAL""
-        fi
-        ;;
    --erl)
        I=$(expr $I + 1)
        eval "VAL=\${$I}"
        ERL="$ERL "$VAL""
        ;;
-    --werl)
-        USE_WERL=true
-        ;;
    *)
        break
        ;;
@@ -103,24 +63,9 @@ done
 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")

-if [ "$OSTYPE" = "cygwin" ]; then SCRIPT_PATH=$(cygpath -m "$SCRIPT_PATH"); fi
-if [ "$MODE" != "iex" ]; then ERL="-noshell -s elixir start_cli $ERL"; fi
-
-# Check for terminal support
-if [ "$OS" != "Windows_NT" ]; then
-  if test -t 1 -a -t 2; then ERL="-elixir ansi_enabled true $ERL"; fi
+if [ -f "$SCRIPT_PATH/../releases/RELEASES" ] && [ -f "$SCRIPT_PATH/erl" ]
+then
+  "$SCRIPT_PATH"/erl -env ERL_LIBS $ERL_LIBS:"$SCRIPT_PATH/../lib" -boot elixir -noshell $ELIXIR_ERL_OPTS $ERL -s elixir start_cli -extra "$@"
+else
+  erl -env ERL_LIBS $ERL_LIBS:"$SCRIPT_PATH/../lib" -noshell $ELIXIR_ERL_OPTS $ERL -s elixir start_cli -extra "$@"
 fi
-
-if [ "$OS" = "Windows_NT" ] && [ $USE_WERL ]; then
-    ERL_EXEC="werl"
-fi
-
-if [ -z "$ERL_PATH" ]; then
-  if [ -f "$SCRIPT_PATH/../releases/RELEASES" ] && [ -f "$SCRIPT_PATH/erl" ]; then
-    ERL_PATH="$SCRIPT_PATH"/"$ERL_EXEC"
-  else
-    ERL_PATH="$ERL_EXEC"
-  fi
-fi
-
-exec "$ERL_PATH" -pa "$SCRIPT_PATH"/../lib/*/ebin $ELIXIR_ERL_OPTIONS $ERL -extra "$@"
@@ -1,113 +1,22 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-setlocal
-if    ""%1""==""""       goto documentation
-if /I ""%1""==""--help"" goto documentation
-if /I ""%1""==""-h""     goto documentation
-if /I ""%1""==""/h""     goto documentation
-if    ""%1""==""/?""     goto documentation
-goto parseopts
-
+@echo off
+if "%*" == "" (
+	goto documentation
+) else (
+	goto run 
+) 
 :documentation
 echo Usage: %~nx0 [options] [.exs file] [data]
 echo.
-echo   -v                          Prints version and exits
-echo   -e COMMAND                  Evaluates the given command (*)
-echo   -r FILE                     Requires the given files/patterns (*)
-echo   -S SCRIPT                   Finds and executes the given script in PATH
-echo   -pr FILE                    Requires the given files/patterns in parallel (*)
-echo   -pa PATH                    Prepends the given path to Erlang code path (*)
-echo   -pz PATH                    Appends the given path to Erlang code path (*)
-echo.
-echo   --app APP                   Starts the given app and its dependencies (*)
-echo   --cookie COOKIE             Sets a cookie for this distributed node
-echo   --detached                  Starts the Erlang VM detached from console
-echo   --erl SWITCHES              Switches to be passed down to Erlang (*)
-echo   --hidden                    Makes a hidden node
-echo   --logger-otp-reports BOOL   Enables or disables OTP reporting
-echo   --logger-sasl-reports BOOL  Enables or disables SASL reporting
-echo   --name NAME                 Makes and assigns a name to the distributed node
-echo   --no-halt                   Does not halt the Erlang VM after execution
-echo   --sname NAME                Makes and assigns a short name to the distributed node
-echo   --werl                      Uses Erlang's Windows shell GUI
+echo  -v              Prints version and exit
+echo  -e command    Evaluates the given command (*)
+echo  -r command    Requires the given file/pattern (*)
+echo  -pr command   Requires the given file/pattern in parallel (*)
+echo  -pa path     Prepend the given path to Erlang code path (*)
+echo  -pz path      Append the given path to Erlang code path (*)
+echo  --no-halt       Do not halt the Erlang VM after execution
 echo.
 echo ** Options marked with (*) can be given more than once
 echo ** Options given after the .exs file or -- are passed down to the executed code
-echo ** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS or --erl
-goto end
-
-:parseopts
-
-rem Parameters for Erlang
-set parsErlang=
-
-rem Make sure we keep a copy of all parameters
-set allPars=%*
-
-rem Get the original path name from the batch file
-set originPath=%~dp0
-
-rem Optional parameters before the "-extra" parameter
-set beforeExtra=
-
-rem Flag which determines whether or not to use werl vs erl
-set useWerl=0
-
-rem Designates which mode / Elixir component to run as
-set runMode="elixir"
-
-rem Recursive loop called for each parameter that parses the cmd line parameters
-:startloop
-set par="%1"
-shift
-if "%par%"=="" (
-  rem if no parameters defined
-  goto expand_erl_libs
-)
-if "%par%"=="""" (
-  rem if no parameters defined - special case for parameter that is already quoted
-  goto expand_erl_libs
-)
-rem ******* EXECUTION OPTIONS **********************
-if "%par%"==""--werl"" (set useWerl=1)
-if "%par%"==""+iex"" (set runMode="iex")
-rem ******* ELIXIR PARAMETERS **********************
-rem Note: we don't have to do anything with options that don't take an argument
-if """"=="%par:-e=%"      (shift)
-if """"=="%par:-r=%"      (shift)
-if """"=="%par:-pr=%"     (shift)
-if """"=="%par:-pa=%"     (shift)
-if """"=="%par:-pz=%"     (shift)
-if """"=="%par:--app=%"   (shift)
-if """"=="%par:--remsh=%" (shift)
-rem ******* ERLANG PARAMETERS **********************
-if """"=="%par:--detached=%"            (set parsErlang=%parsErlang% -detached)
-if """"=="%par:--hidden=%"              (set parsErlang=%parsErlang% -hidden)
-if """"=="%par:--cookie=%"              (set parsErlang=%parsErlang% -setcookie %1 && shift)
-if """"=="%par:--sname=%"               (set parsErlang=%parsErlang% -sname %1 && shift)
-if """"=="%par:--name=%"                (set parsErlang=%parsErlang% -name %1 && shift)
-if """"=="%par:--logger-otp-reports=%"  (set parsErlang=%parsErlang% -logger handle_otp_reports %1 && shift)
-if """"=="%par:--logger-sasl-reports=%" (set parsErlang=%parsErlang% -logger handle_sasl_reports %1 && shift)
-if """"=="%par:--erl=%"                 (set beforeExtra=%beforeExtra% %~1 && shift)
-goto:startloop
-
-rem ******* assume all pre-params are parsed ********************
-:expand_erl_libs
-rem ******* expand all ebin paths as Windows does not support the ..\*\ebin wildcard ********************
-setlocal enabledelayedexpansion
-set ext_libs=
-for  /d %%d in ("%originPath%..\lib\*.") do (
-  set ext_libs=!ext_libs! -pa "%%~fd\ebin"
-)
-setlocal disabledelayedexpansion
-
+echo ** Options can be passed to the erlang runtime using ELIXIR_ERL_OPTS
 :run
-if not %runMode% == "iex" (
-  set beforeExtra=-noshell -s elixir start_cli %beforeExtra%
-)
-if %useWerl% equ 1 (
-  start werl.exe %ext_libs% %ELIXIR_ERL_OPTIONS% %parsErlang% %beforeExtra% -extra %*
-) else (
-  erl.exe %ext_libs% %ELIXIR_ERL_OPTIONS% %parsErlang% %beforeExtra% -extra %*
-)
-:end
-endlocal
+erl -env ERL_LIBS %ERL_LIBS%;"%~dp0\..\lib" -noshell %ELIXIR_ERL_OPTS% -s elixir start_cli -extra %*
@@ -1,23 +1,20 @@
 #!/bin/sh
-if [ $# -eq 0 ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
+if [ $# -eq 0 ]; then
  echo "Usage: `basename $0` [elixir switches] [compiler switches] [.ex files]

-  -o                   The directory to output compiled files
-  --no-docs            Do not attach documentation to compiled modules
-  --no-debug-info      Do not attach debug info to compiled modules
-  --verbose            Print compilation status
-  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+  -o              The directory to output compiled files
+  --no-docs       Do not attach documentation with compiled code
+  --debug-info    Attach debug info to compiled modules
  --ignore-module-conflict

 ** Options given after -- are passed down to the executed code
-** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS
-** Options can be passed to the Erlang compiler using ERL_COMPILER_OPTIONS" >&2
+** Options can be passed to the erlang runtime using ELIXIR_ERL_OPTS" >&2
  exit 1
 fi

 readlink_f () {
  cd "$(dirname "$1")" > /dev/null
-  filename="$(basename "$1")"
+  local filename="$(basename "$1")"
  if [ -h "$filename" ]; then
    readlink_f "$(readlink "$filename")"
  else
@@ -27,4 +24,4 @@ readlink_f () {

 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-exec "$SCRIPT_PATH"/elixir +elixirc "$@"
+"$SCRIPT_PATH"/elixir --compile "$@"
@@ -1,33 +1,22 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-setlocal
-set argc=0
-for %%A in (%*) do (
-  if /I "%%A"=="--help" goto documentation
-  if /I "%%A"=="-h"     goto documentation
-  if /I "%%A"=="/h"     goto documentation
-  if    "%%A"=="/?"     goto documentation
-  set /A argc+=1
-)
-if %argc%==0 goto documentation
-goto run
-
+@echo off
+if "%*" == "" (
+	goto documentation
+) else (
+	goto run 
+) 
 :documentation
-echo Usage: %~nx0 [elixir switches] [compiler switches] [.ex files]
+echo Usage: %~nx0 [switches] [.ex files]
 echo.
-echo  -o                   The directory to output compiled files
-echo  --no-docs            Do not attach documentation to compiled modules
-echo  --no-debug-info      Do not attach debug info to compiled modules
-echo  --verbose            Print compilation status
-echo  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+echo  -v              Prints version and exit
+echo  -o              The directory to output compiled files
+echo  -pa path      Prepend the given path to Erlang code path (*)
+echo  -pz path      Append the given path to Erlang code path (*)
+echo  --no-docs       Do not attach documentation with compiled code
+echo  --debug-info    Attach debug info to compiled modules
 echo  --ignore-module-conflict
 echo.
+echo ** Options marked with (*) can be given more than once
 echo ** Options given after -- are passed down to the executed code
-echo ** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS
-echo ** Options can be passed to the Erlang compiler using ERL_COMPILER_OPTIONS
-goto end
-
+echo ** Options can be passed to the erlang runtime using ELIXIR_ERL_OPTS" >&2
 :run
-call "%~dp0\elixir.bat" +elixirc %*
-
-:end
-endlocal
+call "%~dp0\elixir.bat" --compile %*
@@ -1,40 +1,7 @@
 #!/bin/sh
-if [ $# -gt 0 ] && ([ "$1" = "--help" ] || [ "$1" = "-h" ]); then
-  echo "Usage: `basename $0` [options] [.exs file] [data]
-
-  -v                          Prints version and exits
-  -e COMMAND                  Evaluates the given command (*)
-  -r FILE                     Requires the given files/patterns (*)
-  -S SCRIPT                   Finds and executes the given script in PATH
-  -pr FILE                    Requires the given files/patterns in parallel (*)
-  -pa PATH                    Prepends the given path to Erlang code path (*)
-  -pz PATH                    Appends the given path to Erlang code path (*)
-
-  --app APP                   Starts the given app and its dependencies (*)
-  --cookie COOKIE             Sets a cookie for this distributed node
-  --detached                  Starts the Erlang VM detached from console
-  --erl SWITCHES              Switches to be passed down to Erlang (*)
-  --hidden                    Makes a hidden node
-  --logger-otp-reports BOOL   Enables or disables OTP reporting
-  --logger-sasl-reports BOOL  Enables or disables SASL reporting
-  --name NAME                 Makes and assigns a name to the distributed node
-  --no-halt                   Does not halt the Erlang VM after execution
-  --sname NAME                Makes and assigns a short name to the distributed node
-  --werl                      Uses Erlang's Windows shell GUI (Windows only)
-
-  --dot-iex PATH              Overrides default .iex.exs file and uses path instead;
-                              path can be empty, then no file will be loaded
-  --remsh NAME                Connects to a node using a remote shell
-
-** Options marked with (*) can be given more than once
-** Options given after the .exs file or -- are passed down to the executed code
-** Options can be passed to the VM using ELIXIR_ERL_OPTIONS or --erl" >&2
-  exit 1
-fi
-
 readlink_f () {
  cd "$(dirname "$1")" > /dev/null
-  filename="$(basename "$1")"
+  local filename="$(basename "$1")"
  if [ -h "$filename" ]; then
    readlink_f "$(readlink "$filename")"
  else
@@ -44,4 +11,4 @@ readlink_f () {

 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user Elixir.IEx.CLI" +iex "$@"
+"$SCRIPT_PATH"/elixir --no-halt -e "IEx.cli" "$@"
@@ -1,45 +1,2 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
-setlocal
-if /I ""%1""==""--help"" goto documentation
-if /I ""%1""==""-h""     goto documentation
-if /I ""%1""==""/h""     goto documentation
-if    ""%1""==""/?""     goto documentation
-goto run
-
-:documentation
-echo Usage: %~nx0 [options] [.exs file] [data]
-echo.
-echo  -v                          Prints version and exits
-echo  -e COMMAND                  Evaluates the given command (*)
-echo  -r FILE                     Requires the given files/patterns (*)
-echo  -S SCRIPT                   Finds and executes the given script in PATH
-echo  -pr FILE                    Requires the given files/patterns in parallel (*)
-echo  -pa PATH                    Prepends the given path to Erlang code path (*)
-echo  -pz PATH                    Appends the given path to Erlang code path (*)
-echo.
-echo  --app APP                   Starts the given app and its dependencies (*)
-echo  --cookie COOKIE             Sets a cookie for this distributed node
-echo  --detached                  Starts the Erlang VM detached from console
-echo  --erl SWITCHES              Switches to be passed down to Erlang (*)
-echo  --hidden                    Makes a hidden node
-echo  --logger-otp-reports BOOL   Enables or disables OTP reporting
-echo  --logger-sasl-reports BOOL  Enables or disables SASL reporting
-echo  --name NAME                 Makes and assigns a name to the distributed node
-echo  --no-halt                   Does not halt the Erlang VM after execution
-echo  --sname NAME                Makes and assigns a short name to the distributed node
-echo  --werl                      Uses Erlang's Windows shell GUI (Windows only)
-echo.
-echo  --dot-iex PATH              Overrides default .iex.exs file and uses path instead;
-echo                              path can be empty, then no file will be loaded
-echo  --remsh NAME                Connects to a node using a remote shell
-echo.
-echo ** Options marked with (*) can be given more than once
-echo ** Options given after the .exs file or -- are passed down to the executed code
-echo ** Options can be passed to the Erlang VM using ELIXIR_ERL_OPTIONS or --erl
-goto end
-
-:run
-@if defined IEX_WITH_WERL (@set __ELIXIR_IEX_FLAGS=--werl) else (set __ELIXIR_IEX_FLAGS=)
-call "%~dp0\elixir.bat" +iex --erl "-user Elixir.IEx.CLI" --no-halt %__ELIXIR_IEX_FLAGS% %*
-:end
-endlocal
+@echo off
+call "%~dp0\elixir.bat" --no-halt -e "IEx.cli" %*
@@ -1,3 +1,3 @@
 #!/usr/bin/env elixir
 Mix.start
-Mix.CLI.main
+Mix.CLI.run
@@ -1,2 +1,2 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-call "%~dp0\elixir.bat" "%~dp0\mix" %*
+@echo off
+call "%~dp0\elixir.bat" "%~dp0\mix" %*
@@ -1,23 +0,0 @@
-# Store path to mix.bat as a FileInfo object
-$mixBatPath = (Get-ChildItem (((Get-ChildItem $MyInvocation.MyCommand.Path).Directory.FullName) + '\mix.bat'))
-$newArgs = @()
-
-for ($i = 0; $i -lt $args.length; $i++)
-{
-  if ($args[$i] -is [array])
-  {
-    # Commas created the array so we need to reintroduce those commas
-    for ($j = 0; $j -lt $args[$i].length - 1; $j++)
-    {
-      $newArgs += ($args[$i][$j] + ',')
-    }
-    $newArgs += $args[$i][-1]
-  }
-  else
-  {
-    $newArgs += $args[$i]
-  }
-}
-
-# Corrected arguments are ready to pass to batch file
-& $mixBatPath $newArgs
@@ -1,48 +1,31 @@
-defmodule EEx.SyntaxError do
-  defexception [:message, :file, :line]
-
-  def message(exception) do
-    "#{exception.file}:#{exception.line}: #{exception.message}"
-  end
-end
+defexception EEx.SyntaxError, message: nil

 defmodule EEx do
-  @moduledoc ~S"""
+  @moduledoc %B"""
  EEx stands for Embedded Elixir. It allows you to embed
-  Elixir code inside a string in a robust way.
+  Elixir code inside a string in a robust way:

-      iex> EEx.eval_string "foo <%= bar %>", [bar: "baz"]
-      "foo baz"
+      EEx.eval_string "foo <%= bar %>", [bar: "baz"]
+      #=> "foo baz"

  ## API

  This module provides 3 main APIs for you to use:

-    1. Evaluate a string (`eval_string`) or a file (`eval_file`)
-       directly. This is the simplest API to use but also the
-       slowest, since the code is evaluated and not compiled before.
+  1) Evaluate a string (`eval_string`) or a file (`eval_file`)
+     directly. This is the simplest API to use but also the
+     slowest, since the code is evaluated and not compiled before;

-    2. Define a function from a string (`function_from_string`)
-       or a file (`function_from_file`). This allows you to embed
-       the template as a function inside a module which will then
-       be compiled. This is the preferred API if you have access
-       to the template at compilation time.
+  2) Define a function from a string (`function_from_string`)
+     or a file (`function_from_file`). This allows you to embed
+     the template as a function inside a module which will then
+     be compiled. This is the preferred API if you have access
+     to the template at compilation time;

-    3. Compile a string (`compile_string`) or a file (`compile_file`)
-       into Elixir syntax tree. This is the API used by both functions
-       above and is available to you if you want to provide your own
-       ways of handling the compiled template.
-
-  ## Options
-
-  All functions in this module accept EEx-related options.
-  They are:
-
-    * `:line` - the line to be used as the template start. Defaults to 1.
-    * `:file` - the file to be used in the template. Defaults to the given
-      file the template is read from or to "nofile" when compiling from a string.
-    * `:engine` - the EEx engine to be used for compilation.
-    * `:trim` - trims whitespace left/right of quotation tags
+  3) Compile a string (`compile_string`) or a file (`compile_file`)
+     into Elixir syntax tree. This is the API used by both functions
+     above and is available to you if you want to provide your own
+     ways of handling the compiled template.

  ## Engine

@@ -58,14 +41,12 @@ defmodule EEx do

      <% Elixir expression - inline with output %>
      <%= Elixir expression - replace with result %>
-      <%% EEx quotation - returns the contents inside %>
-      <%# Comments - they are discarded from source %>

  All expressions that output something to the template
  **must** use the equals sign (`=`). Since everything in
-  Elixir is an expression, there are no exceptions for this rule.
-  For example, while some template languages would special-case
-  `if/2` clauses, they are treated the same in EEx and
+  Elixir is a macro, there are no exceptions for this rule.
+  For example, while some template languages would special-
+  case `if` clauses, they are treated the same in EEx and
  also require `=` in order to have their result printed:

      <%= if true do %>
@@ -83,49 +64,43 @@ defmodule EEx do
  An example is the `@` macro which allows easy data access
  in a template:

-      iex> EEx.eval_string "<%= @foo %>", assigns: [foo: 1]
-      "1"
+      EEx.eval_string "<%= @foo %>", assigns: [foo: 1]
+      #=> 1

-  In other words, `<%= @foo %>` translates to:
+  In other words, <%= @foo %> is simply translated to:

-      <%= {:ok, v} = Access.fetch(assigns, :foo); v %>
+      <%= Keyword.get assigns, :foo %>

-  The `assigns` extension is useful when the number of variables
+  The assigns extension is useful when the number of variables
  required by the template is not specified at compilation time.
  """

  @doc """
  Generates a function definition from the string.
-
  The kind (`:def` or `:defp`) must be given, the
  function name, its arguments and the compilation options.

  ## Examples

-      iex> defmodule Sample do
-      ...>   require EEx
-      ...>   EEx.function_from_string :def, :sample, "<%= a + b %>", [:a, :b]
-      ...> end
-      iex> Sample.sample(1, 2)
-      "3"
+      defmodule Sample do
+        require EEx
+        EEx.function_from_string :def, :sample, "<%= a + b %>", [:a, :b]
+      end
+
+      Sample.sample(1, 2) #=> "3"

  """
-  defmacro function_from_string(kind, name, source, args \\ [], options \\ []) do
-    quote bind_quoted: binding() do
-      info = Keyword.merge [file: __ENV__.file, line: __ENV__.line], options
-      args = Enum.map args, fn arg -> {arg, [line: info[:line]], nil} end
-      compiled = EEx.compile_string(source, info)
-
-      case kind do
-        :def  -> def(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
-        :defp -> defp(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
-      end
+  defmacro function_from_string(kind, name, source, args // [], options // []) do
+    info = [file: __CALLER__.file, line: __CALLER__.line + 1]
+    quote do
+      info = Keyword.merge unquote(info), unquote(options)
+      EEx.function_from_quoted(__MODULE__, unquote(kind), unquote(name),
+        unquote(args), EEx.compile_string(unquote(source), info), info)
    end
  end

  @doc """
  Generates a function definition from the file contents.
-
  The kind (`:def` or `:defp`) must be given, the
  function name, its arguments and the compilation options.

@@ -147,71 +122,62 @@ defmodule EEx do
      Sample.sample(1, 2) #=> "3"

  """
-  defmacro function_from_file(kind, name, file, args \\ [], options \\ []) do
-    quote bind_quoted: binding() do
-      info = Keyword.merge options, [file: file, line: 1]
-      args = Enum.map args, fn arg -> {arg, [line: 1], nil} end
-      compiled = EEx.compile_file(file, info)
+  defmacro function_from_file(kind, name, filename, args // [], options // []) do
+    quote do
+      file = unquote(filename)
+      info = Keyword.merge unquote(options), [file: file, line: 1]

-      @external_resource file
      @file file
-      case kind do
-        :def  -> def(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
-        :defp -> defp(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
-      end
+      EEx.function_from_quoted(__MODULE__, unquote(kind), unquote(name),
+        unquote(args), EEx.compile_file(file, info), info)
    end
  end

  @doc """
-  Gets a string `source` and generate a quoted expression
+  Get a string `source` and generate a quoted expression
  that can be evaluated by Elixir or compiled to a function.
  """
-  @spec compile_string(String.t, Keyword.t) :: Macro.t | no_return
-  def compile_string(source, options \\ []) when is_binary(source) and is_list(options) do
+  def compile_string(source, options // []) do
    EEx.Compiler.compile(source, options)
  end

  @doc """
-  Gets a `filename` and generate a quoted expression
+  Get a `filename` and generate a quoted expression
  that can be evaluated by Elixir or compiled to a function.
  """
-  @spec compile_file(String.t, Keyword.t) :: Macro.t | no_return
-  def compile_file(filename, options \\ []) when is_binary(filename) and is_list(options) do
+  def compile_file(filename, options // []) do
    options = Keyword.merge options, [file: filename, line: 1]
    compile_string(File.read!(filename), options)
  end

  @doc """
-  Gets a string `source` and evaluate the values using the `bindings`.
+  Get a string `source` and evaluate the values using the `bindings`.

  ## Examples

-      iex> EEx.eval_string "foo <%= bar %>", [bar: "baz"]
-      "foo baz"
+      EEx.eval_string "foo <%= bar %>", [bar: "baz"]
+      #=> "foo baz"

  """
-  @spec eval_string(String.t, Keyword.t, Keyword.t) :: any
-  def eval_string(source, bindings \\ [], options \\ [])
-      when is_binary(source) and is_list(bindings) and is_list(options) do
+  def eval_string(source, bindings // [], options // []) do
    compiled = compile_string(source, options)
    do_eval(compiled, bindings, options)
  end

  @doc """
-  Gets a `filename` and evaluate the values using the `bindings`.
+  Get a `filename` and evaluate the values using the `bindings`.

  ## Examples

-      # sample.eex
+      # sample.ex
      foo <%= bar %>

      # iex
-      EEx.eval_file "sample.eex", [bar: "baz"] #=> "foo baz"
+      EEx.eval_file "sample.ex", [bar: "baz"]
+      #=> "foo baz"

  """
-  @spec eval_file(String.t, Keyword.t, Keyword.t) :: any
-  def eval_file(filename, bindings \\ [], options \\ [])
-      when is_binary(filename) and is_list(bindings) and is_list(options) do
+  def eval_file(filename, bindings // [], options // []) do
    options  = Keyword.put options, :file, filename
    compiled = compile_file(filename, options)
    do_eval(compiled, bindings, options)
@@ -219,8 +185,17 @@ defmodule EEx do

  ### Helpers

+  @doc false
+  def function_from_quoted(module, kind, name, args, source, info) do
+    args  = Enum.map args, fn arg -> { arg, 0, nil } end
+    quote = quote do
+      unquote(kind).(unquote(name).(unquote_splicing(args)), do: unquote(source))
+    end
+    Module.eval_quoted module, quote, [], info
+  end
+
  defp do_eval(compiled, bindings, options) do
-    {result, _} = Code.eval_quoted(compiled, bindings, options)
+    { result, _ } = Code.eval_quoted(compiled, bindings, options)
    result
  end
 end
@@ -1,126 +1,117 @@
+defrecord EEx.State, engine: EEx.SmartEngine, dict: [], file: 'nofile', line: 1, start_line: 1
+
 defmodule EEx.Compiler do
  @moduledoc false

-  # When changing this setting, don't forget to update the docs for EEx
-  @default_engine EEx.SmartEngine
-
  @doc """
  This is the compilation entry point. It glues the tokenizer
  and the engine together by handling the tokens and invoking
  the engine every time a full expression or text is received.
  """
-  @spec compile(String.t, Keyword.t) :: Macro.t | no_return
-  def compile(source, opts) when is_binary(source) and is_list(opts) do
-    file   = opts[:file] || "nofile"
-    line   = opts[:line] || 1
-    trim   = opts[:trim] || false
-    case EEx.Tokenizer.tokenize(source, line, trim: trim) do
-      {:ok, tokens} ->
-        state = %{engine: opts[:engine] || @default_engine,
-                  file: file, line: line, quoted: [], start_line: nil}
-        generate_buffer(tokens, state.engine.init(opts), [], state)
-      {:error, line, message} ->
-        raise EEx.SyntaxError, line: line, file: file, message: message
-    end
+  def compile(source, options) do
+    line   = Keyword.get(options, :line, 1)
+    tokens = EEx.Tokenizer.tokenize(source, line)
+    state  = EEx.State.new(options)
+    generate_buffer(tokens, "", [], state)
  end

-  # Generates the buffers by handling each expression from the tokenizer.
-  # It returns Macro.t/0 or it raises.
+  # Generates the buffers by handling each expression from the tokenizer

-  defp generate_buffer([{:text, chars} | t], buffer, scope, state) do
-    buffer = state.engine.handle_text(buffer, IO.chardata_to_string(chars))
+  defp generate_buffer([{ :text, _line, chars }|t], buffer, scope, state) do
+    buffer = state.engine.handle_text(buffer, chars)
    generate_buffer(t, buffer, scope, state)
  end

-  defp generate_buffer([{:expr, line, mark, chars} | t], buffer, scope, state) do
-    expr = Code.string_to_quoted!(chars, [line: line, file: state.file])
-    buffer = state.engine.handle_expr(buffer, IO.chardata_to_string(mark), expr)
+  defp generate_buffer([{ :expr, line, mark, chars }|t], buffer, scope, state) do
+    expr = maybe_block Erlang.elixir_translator.forms(chars, line, state.file)
+    buffer = state.engine.handle_expr(buffer, mark, expr)
    generate_buffer(t, buffer, scope, state)
  end

-  defp generate_buffer([{:start_expr, start_line, mark, chars} | t], buffer, scope, state) do
-    {contents, line, t} = look_ahead_text(t, start_line, chars)
-    {contents, t} = generate_buffer(t, "", [contents | scope],
-                                    %{state | quoted: [], line: line, start_line: start_line})
-    buffer = state.engine.handle_expr(buffer, IO.chardata_to_string(mark), contents)
-    generate_buffer(t, buffer, scope, state)
+  defp generate_buffer([{ :start_expr, line, mark, chars }|t], buffer, scope, state) do
+    { contents, t } = generate_buffer(t, "", [chars|scope], state.dict([]).line(line).start_line(line))
+    buffer = state.engine.handle_expr(buffer, mark, contents)
+    generate_buffer(t, buffer, scope, state.dict([]))
  end

-  defp generate_buffer([{:middle_expr, line, _, chars} | t], buffer, [current | scope], state) do
-    {wrapped, state} = wrap_expr(current, line, buffer, chars, state)
-    generate_buffer(t, "", [wrapped | scope], %{state | line: line})
+  defp generate_buffer([{ :middle_expr, line, _, chars }|t], buffer, [current|scope], state) do
+    { wrapped, state } = wrap_expr(current, line, buffer, chars, state)
+    generate_buffer(t, "", [wrapped|scope], state.line(line))
  end

-  defp generate_buffer([{:end_expr, line, _, chars} | t], buffer, [current | _], state) do
-    {wrapped, state} = wrap_expr(current, line, buffer, chars, state)
-    tuples = Code.string_to_quoted!(wrapped, [line: state.start_line, file: state.file])
-    buffer = insert_quoted(tuples, state.quoted)
-    {buffer, t}
+  defp generate_buffer([{ :end_expr, line, _, chars }|t], buffer, [current|_], state) do
+    { wrapped, state } = wrap_expr(current, line, buffer, chars, state)
+    tuples = maybe_block Erlang.elixir_translator.forms(wrapped, state.start_line, state.file)
+    buffer = insert_quotes(tuples, state.dict)
+    { buffer, t }
  end

-  defp generate_buffer([{:end_expr, line, _, chars} | _], _buffer, [], state) do
-    raise EEx.SyntaxError, message: "unexpected token #{inspect chars}", file: state.file, line: line
+  defp generate_buffer([{ :end_expr, line, _, chars }|_], _buffer, [], _state) do
+    raise EEx.SyntaxError, message: "unexpected token: #{inspect chars} at line #{inspect line}"
  end

-  defp generate_buffer([], buffer, [], state) do
-    state.engine.handle_body(buffer)
+  defp generate_buffer([], buffer, [], _state) do
+    buffer
  end

-  defp generate_buffer([], _buffer, _scope, state) do
-    raise EEx.SyntaxError, message: "unexpected end of string, expected a closing '<% end %>'",
-                           file: state.file, line: state.line
+  defp generate_buffer([], _buffer, _scope, _state) do
+    raise EEx.SyntaxError, message: "unexpected end of string. expecting a closing <% end %>."
  end

  # Creates a placeholder and wrap it inside the expression block

  defp wrap_expr(current, line, buffer, chars, state) do
    new_lines = List.duplicate(?\n, line - state.line)
-    key = length(state.quoted)
-    placeholder = '__EEX__(' ++ Integer.to_charlist(key) ++ ');'
-    {current ++ placeholder ++ new_lines ++ chars,
-     %{state | quoted: [{key, buffer} | state.quoted]}}
-  end

-  # Look text ahead on expressions
-
-  defp look_ahead_text([{:text, text}, {:middle_expr, line, _, chars} | t]=list, start, contents) do
-    if only_spaces?(text) do
-      {contents ++ text ++ chars, line, t}
+    if state.dict == [] and is_empty?(buffer) do
+      { current ++ new_lines ++ chars, state }
    else
-      {contents, start, list}
+      key = length(state.dict)
+      placeholder = '__EEX__(' ++ integer_to_list(key) ++ ');'
+      { current ++ placeholder ++ new_lines ++ chars, state.prepend_dict([{key, buffer}]) }
    end
  end
-  defp look_ahead_text([{:middle_expr, line, _, chars} | t], _start, contents) do
-    {contents ++ chars, line, t}
-  end
-  defp look_ahead_text(t, start, contents) do
-    {contents, start, t}
+
+  # Check if the syntax node represents an empty string
+
+  defp is_empty?(bin) when is_binary(bin) do
+    bc(<<c>> inbits bin, not c in [?\s,?\t,?\r,?\n], do: <<c>>) == ""
  end

-  defp only_spaces?(chars) do
-    Enum.all?(chars, &(&1 in [?\s, ?\t, ?\r, ?\n]))
+  defp is_empty?({ :<>, _, [left, right] }) do
+    is_empty?(left) and is_empty?(right)
  end

+  defp is_empty?(_) do
+    false
+  end
+
+  # Block wrapping
+
+  defp maybe_block([]),    do: nil
+  defp maybe_block([h]),   do: h
+  defp maybe_block(other), do: { :__block__, 0, other }
+
  # Changes placeholder to real expression

-  defp insert_quoted({:__EEX__, _, [key]}, quoted) do
-    {^key, value} = List.keyfind quoted, key, 0
+  defp insert_quotes({ :__EEX__, _, [key] }, dict) do
+    { ^key, value } = List.keyfind dict, key, 1
    value
  end

-  defp insert_quoted({left, line, right}, quoted) do
-    {insert_quoted(left, quoted), line, insert_quoted(right, quoted)}
+  defp insert_quotes({ left, line, right }, dict) do
+    { insert_quotes(left, dict), line, insert_quotes(right, dict) }
  end

-  defp insert_quoted({left, right}, quoted) do
-    {insert_quoted(left, quoted), insert_quoted(right, quoted)}
+  defp insert_quotes({ left, right }, dict) do
+    { insert_quotes(left, dict), insert_quotes(right, dict) }
  end

-  defp insert_quoted(list, quoted) when is_list(list) do
-    Enum.map list, &insert_quoted(&1, quoted)
+  defp insert_quotes(list, dict) when is_list(list) do
+    Enum.map list, insert_quotes(&1, dict)
  end

-  defp insert_quoted(other, _quoted) do
+  defp insert_quotes(other, _dict) do
    other
  end
 end
@@ -1,116 +1,25 @@
 defmodule EEx.Engine do
-  @moduledoc ~S"""
-  Basic EEx engine that ships with Elixir.
+  @moduledoc %B"""
+  This is the basic EEx engine that ships with Elixir.
+  An engine needs to implement two functions:

-  An engine needs to implement four functions:
+  * `handle_text(buffer, text)` - it receives the buffer,
+    the text and must return a new quoted expression;

-    * `init(opts)` - returns the initial buffer
+  * `handle_expr(buffer, marker, expr)` - it receives the buffer,
+    the marker, the expr and must return a new quoted expression;

-    * `handle_body(quoted)` - receives the final built quoted
-      expression, should do final post-processing and return a
-      quoted expression.
+    The marker is what follows exactly after `<%`. For example,
+    `<% foo %>` has an empty marker, but `<%= foo %>` has `'='`
+    as marker. The allowed markers so far are:

-    * `handle_text(buffer, text)` - it receives the buffer,
-      the text and must return a new quoted expression.
+    * `''`
+    * `'='`

-    * `handle_expr(buffer, marker, expr)` - it receives the buffer,
-      the marker, the expr and must return a new quoted expression.
-
-      The marker is what follows exactly after `<%`. For example,
-      `<% foo %>` has an empty marker, but `<%= foo %>` has `"="`
-      as marker. The allowed markers so far are: `""` and `"="`.
-
-      Read `handle_expr/3` below for more information about the markers
-      implemented by default by this engine.
-
-  `EEx.Engine` can be used directly if one desires to use the
-  default implementations for the functions above.
+    Read `handle_expr/3` below for more information about the markers
+    implemented by default by this engine.
  """

-  @callback init(opts :: Keyword.t) :: Macro.t
-  @callback handle_body(quoted :: Macro.t) :: Macro.t
-  @callback handle_text(buffer :: Macro.t, text :: String.t) :: Macro.t
-  @callback handle_expr(buffer :: Macro.t, marker :: String.t, expr :: Macro.t) :: Macro.t
-
-  @doc false
-  defmacro __using__(_) do
-    quote do
-      @behaviour EEx.Engine
-
-      def init(opts) do
-        EEx.Engine.init(opts)
-      end
-
-      def handle_body(quoted) do
-        EEx.Engine.handle_body(quoted)
-      end
-
-      def handle_text(buffer, text) do
-        EEx.Engine.handle_text(buffer, text)
-      end
-
-      def handle_expr(buffer, marker, expr) do
-        EEx.Engine.handle_expr(buffer, marker, expr)
-      end
-
-      defoverridable [handle_body: 1, handle_expr: 3, handle_text: 2, init: 1]
-    end
-  end
-
-  @doc """
-  Handles assigns in quoted expressions.
-
-  A warning will be printed on missing assigns.
-  Future versions will raise.
-
-  This can be added to any custom engine by invoking
-  `handle_assign/1` with `Macro.prewalk/2`:
-
-      def handle_expr(buffer, token, expr) do
-        expr = Macro.prewalk(expr, &EEx.Engine.handle_assign/1)
-        EEx.Engine.handle_expr(buffer, token, expr)
-      end
-
-  """
-  @spec handle_assign(Macro.t) :: Macro.t
-  def handle_assign({:@, meta, [{name, _, atom}]}) when is_atom(name) and is_atom(atom) do
-    line = meta[:line] || 0
-    quote line: line, do: EEx.Engine.fetch_assign!(var!(assigns), unquote(name))
-  end
-  def handle_assign(arg) do
-    arg
-  end
-
-  @doc false
-  # TODO: Raise on 2.0
-  @spec fetch_assign!(map, Map.key) :: term | nil
-  def fetch_assign!(assigns, key) do
-    case Access.fetch(assigns, key) do
-      {:ok, val} ->
-        val
-      :error ->
-        keys = Enum.map(assigns, &elem(&1, 0))
-        IO.warn "assign @#{key} not available in EEx template. " <>
-                "Please ensure all assigns are given as options. " <>
-                "Available assigns: #{inspect keys}"
-        nil
-    end
-  end
-
-  @doc """
-  Returns an empty string as initial buffer.
-  """
-  def init(_opts) do
-    ""
-  end
-
-  @doc """
-  The default implementation simply returns the given expression.
-  """
-  def handle_body(quoted) do
-    quoted
-  end
-
  @doc """
  The default implementation simply concatenates text to the buffer.
  """
@@ -126,18 +35,23 @@ defmodule EEx.Engine do

  All other markers are not implemented by this engine.
  """
-  def handle_expr(buffer, "=", expr) do
+  def handle_expr(buffer, '=', expr) do
    quote do
-      tmp1 = unquote(buffer)
-      tmp1 <> String.Chars.to_string(unquote(expr))
+      tmp_1 = unquote(buffer)
+      tmp_2 = to_binary(unquote(expr))
+      tmp_1 <> tmp_2
    end
  end

-  def handle_expr(buffer, "", expr) do
+  def handle_expr(buffer, '', expr) do
    quote do
-      tmp2 = unquote(buffer)
+      tmp = unquote(buffer)
      unquote(expr)
-      tmp2
+      tmp
    end
  end
-end
+
+  def behaviour_info(:callbacks) do
+    [handle_text: 2, handle_expr: 3]
+  end
+end
@@ -1,41 +1,97 @@
-defmodule EEx.SmartEngine do
+defmodule EEx.TransformerEngine do
  @moduledoc """
-  The default engine used by EEx.
+  An abstract engine that is meant to be used and
+  built upon in other modules. This engine implements
+  the `EEx.Engine` behavior and provides a `transform`
+  overridable directive that allows a developer to
+  customize the expression returned by the engine.

-  It includes assigns (like `@foo`) and possibly other
-  conveniences in the future.
+  Check `EEx.AssignsEngine` and `EEx.SmartEngine` for
+  examples of using this module.
+  """
+
+  @doc false
+  defmacro __using__(_) do
+    quote do
+      @behavior EEx.Engine
+
+      def handle_text(buffer, text) do
+        EEx.Engine.handle_text(buffer, text)
+      end
+
+      def handle_expr(buffer, mark, expr) do
+        EEx.Engine.handle_expr(buffer, mark, transform(expr))
+      end
+
+      defp transform({ a, b, c }) do
+        { transform(a), b, transform(c) }
+      end
+
+      defp transform({ a, b }) do
+        { transform(a), transform(b) }
+      end
+
+      defp transform(list) when is_list(list) do
+        lc i inlist list, do: transform(i)
+      end
+
+      defp transform(other) do
+        other
+      end
+
+      defoverridable [transform: 1, handle_expr: 3, handle_text: 2]
+    end
+  end
+end
+
+defmodule EEx.AssignsEngine do
+  @moduledoc """
+  An abstract engine that, when used with the
+  `TransformerEngine`, allows a developer to access
+  assigns using `@` as syntax.
+
+  This engine is included by default on the SmartEngine.

  ## Examples

-      iex> EEx.eval_string("<%= @foo %>", assigns: [foo: 1])
-      "1"
-
-  In the example above, we can access the value `foo` under
-  the binding `assigns` using `@foo`. This is useful because
-  a template, after being compiled, can receive different
-  assigns and would not require recompilation for each
-  variable set.
-
-  Assigns can also be used when compiled to a function:
-
-      # sample.eex
-      <%= @a + @b %>
-
-      # sample.ex
-      defmodule Sample do
-        require EEx
-        EEx.function_from_file :def, :sample, "sample.eex", [:assigns]
+      defmodule MyEngine do
+        use EEx.TransformerEngine
+        use EEx.AssignsEngine
      end

-      # iex
-      Sample.sample(a: 1, b: 2) #=> "3"
+      EEx.eval_string("<%= @foo %>", assigns: [foo: 1])
+      #=> 1

+  In the example above, we can access the value `foo` under
+  the binding `assigns` using `@foo`. This is useful when
+  a template, after compiled, may receive different assigns
+  and the developer don't want to recompile it for each
+  variable set.
  """

-  use EEx.Engine
+  @doc false
+  defmacro __using__(_) do
+    quote unquote: false do
+      defp transform({ :@, line, [{ name, _, atom }] }) when is_atom(name) and is_atom(atom) do
+        quote(do: Keyword.get var!(assigns), unquote(name))
+      end

-  def handle_expr(buffer, mark, expr) do
-    expr = Macro.prewalk(expr, &EEx.Engine.handle_assign/1)
-    super(buffer, mark, expr)
+      defp transform(_) do
+        super
+      end
+
+      defoverridable [transform: 1]
+    end
  end
 end
+
+defmodule EEx.SmartEngine do
+  use EEx.TransformerEngine
+  use EEx.AssignsEngine
+
+  @moduledoc """
+  An engine meant for end-user usage that includes
+  `AssignsEngine` and other conveniences. Read
+  `EEx.AssignsEngine` for examples.
+  """
+end
@@ -1,130 +1,102 @@
 defmodule EEx.Tokenizer do
  @moduledoc false

-  @type content :: IO.chardata
-  @type line :: non_neg_integer
-  @type token :: {:text, content} |
-                 {:expr | :start_expr | :middle_expr | :end_expr, line, '=' | '', content}
-
  @doc """
-  Tokenizes the given charlist or binary.
+  Tokenizes the given char list or binary.
+  It returns 4 different types of tokens as result:

-  It returns {:ok, list} with the following tokens:
+  * { :text, line, contents }
+  * { :expr, line, marker, contents }
+  * { :start_expr, line, marker, contents }
+  * { :end_expr, line, marker, contents }

-    * `{:text, content}`
-    * `{:expr, line, marker, content}`
-    * `{:start_expr, line, marker, content}`
-    * `{:middle_expr, line, marker, content}`
-    * `{:end_expr, line, marker, content}`
-
-  Or `{:error, line, error}` in case of errors.
  """
-  @spec tokenize(binary | charlist, line, Keyword.t) :: {:ok, [token]} | {:error, line, String.t}
-  def tokenize(bin, line, opts \\ [])
-
-  def tokenize(bin, line, opts)
-      when is_binary(bin) and is_integer(line) and line >= 0 and is_list(opts) do
-    tokenize(String.to_charlist(bin), line, opts)
+  def tokenize(bin, line) when is_binary(bin) do
+    tokenize(binary_to_list(bin), line)
  end

-  def tokenize(list, line, opts)
-      when is_list(list) and is_integer(line) and line >= 0 and is_list(opts) do
-    tokenize(list, line, opts, [], [])
+  def tokenize(list, line) do
+    List.reverse(tokenize(list, line, line, [], []))
  end

-  defp tokenize('<%%' ++ t, line, opts, buffer, acc) do
-   tokenize t, line, opts, [?%, ?< | buffer], acc
+  defp tokenize([?<,?%|t], current_line, line, buffer, acc) do
+    { marker, t } = retrieve_marker(t)
+    { expr, new_line, rest } = tokenize_expr t, line, []
+
+    token = token_name(expr)
+    acc   = tokenize_text(current_line, buffer, acc)
+    final = { token, line, marker, List.reverse(expr) }
+    tokenize rest, new_line, new_line, [], [final | acc]
  end

-  defp tokenize('<%#' ++ t, line, opts, buffer, acc) do
-    case expr(t, line, []) do
-      {:error, _, _} = error -> error
-      {:ok, _, new_line, rest} ->
-        {rest, new_line, buffer} = trim_if_needed(rest, new_line, opts, buffer, acc)
-        tokenize rest, new_line, opts, buffer, acc
-    end
+  defp tokenize('\n' ++ t, current_line, line, buffer, acc) do
+    tokenize t, current_line, line + 1, [?\n|buffer], acc
  end

-  defp tokenize('<%' ++ t, line, opts, buffer, acc) do
-    {marker, t} = retrieve_marker(t)
-
-    case expr(t, line, []) do
-      {:error, _, _} = error -> error
-      {:ok, expr, new_line, rest} ->
-        token = token_name(expr)
-        {rest, new_line, buffer} = trim_if_needed(rest, new_line, opts, buffer, acc)
-        acc   = tokenize_text(buffer, acc)
-        final = {token, line, marker, Enum.reverse(expr)}
-        tokenize rest, new_line, opts, [], [final | acc]
-    end
+  defp tokenize([h|t], current_line, line, buffer, acc) do
+    tokenize t, current_line, line, [h|buffer], acc
  end

-  defp tokenize('\n' ++ t, line, opts, buffer, acc) do
-    tokenize t, line + 1, opts, [?\n | buffer], acc
-  end
-
-  defp tokenize([h | t], line, opts, buffer, acc) do
-    tokenize t, line, opts, [h | buffer], acc
-  end
-
-  defp tokenize([], _line, _opts, buffer, acc) do
-    {:ok, Enum.reverse(tokenize_text(buffer, acc))}
+  defp tokenize([], current_line, _line, buffer, acc) do
+    tokenize_text(current_line, buffer, acc)
  end

  # Retrieve marker for <%

  defp retrieve_marker('=' ++ t) do
-    {'=', t}
+    { '=', t }
  end

  defp retrieve_marker(t) do
-    {'', t}
+    { '', t }
  end

  # Tokenize an expression until we find %>

-  defp expr([?%, ?> | t], line, buffer) do
-    {:ok, buffer, line, t}
+  defp tokenize_expr([?%,?>|t], line, buffer) do
+    { buffer, line, t }
  end

-  defp expr('\n' ++ t, line, buffer) do
-    expr t, line + 1, [?\n | buffer]
+  defp tokenize_expr('\n' ++ t, line, buffer) do
+    tokenize_expr t, line + 1, [?\n|buffer]
  end

-  defp expr([h | t], line, buffer) do
-    expr t, line, [h | buffer]
+  defp tokenize_expr([h|t], line, buffer) do
+    tokenize_expr t, line, [h|buffer]
  end

-  defp expr([], line, _buffer) do
-    {:error, line, "missing token '%>'"}
+  # Raise an error if the expected token is not found
+
+  defp tokenize_expr([], _line, _buffer) do
+    raise EEx.SyntaxError, message: "missing token: %>"
  end

  # Receive an expression content and check
  # if it is a start, middle or an end token.
  #
-  # Start tokens finish with "do" and "fn ->"
-  # Middle tokens are marked with "->" or keywords
-  # End tokens contain only the end word and optionally ")"
+  # Start tokens finish with `do` and `fn ->`
+  # Middle tokens are marked with `->` or keywords
+  # End tokens contain only the end word

-  defp token_name([h | t]) when h in [?\s, ?\t, ?)] do
+  defp token_name([h|t]) when h in [?\s, ?\t] do
    token_name(t)
  end

-  defp token_name('od' ++ [h | _]) when h in [?\s, ?\t, ?)] do
+  defp token_name('od' ++ [h|_]) when h in [?\s, ?\t, ?)] do
    :start_expr
  end

  defp token_name('>-' ++ rest) do
-    rest = Enum.reverse(rest)
+    rest = List.reverse(rest)

-    # Tokenize the remaining passing check_terminators as
-    # false, which relax the tokenizer to not error on
-    # unmatched pairs. Then, we check if there is a "fn"
-    # token and, if so, it is not followed by an "end"
-    # token. If this is the case, we are on a start expr.
-    case :elixir_tokenizer.tokenize(rest, 1, file: "eex", check_terminators: false) do
-      {:ok, _line, _column, tokens} ->
-        tokens   = Enum.reverse(tokens)
+    # Tokenize the remaining passing "__internal__" as file,
+    # which relax the tokenizer to not error on unmatched
+    # pairs. Then, we check if there is a "fn" token and,
+    # if so, it is not followed by an "end" token. If this
+    # is the case, we are on a start expr.
+    case :elixir_tokenizer.tokenize(rest, 1, "__internal__") do
+      { :ok, tokens } ->
+        tokens   = List.reverse(tokens)
        fn_index = fn_index(tokens)

        if fn_index && end_index(tokens) > fn_index do
@@ -132,7 +104,7 @@ defmodule EEx.Tokenizer do
        else
          :middle_expr
        end
-      _error ->
+      error ->
        :middle_expr
    end
  end
@@ -148,75 +120,32 @@ defmodule EEx.Tokenizer do
  end

  defp fn_index(tokens) do
-    Enum.find_index tokens, fn
-      {:fn_paren, _} -> true
-      {:fn, _}       -> true
-      _              -> false
-    end
+    Enum.find_index(tokens, function do
+      { :fn_paren, _ } -> true
+      { :fn, _ }       -> true
+      _                -> false
+    end)
  end

  defp end_index(tokens) do
-    Enum.find_index(tokens, &match?({:end, _}, &1)) || :infinity
+    Enum.find_index(tokens, match?({ :end, _ }, &1)) || :infinity
  end

  defp check_spaces(string, token) do
-    if Enum.all?(string, &(&1 in [?\s, ?\t])) do
-      token
-    else
-      :expr
-    end
+    if only_spaces?(string), do: token, else: :expr
  end

+  defp only_spaces?([h|t]) when h in [?\s, ?\t], do: only_spaces?(t)
+  defp only_spaces?(other), do: other == []
+
  # Tokenize the buffered text by appending
  # it to the given accumulator.

-  defp tokenize_text([], acc) do
+  defp tokenize_text(_line, [], acc) do
    acc
  end

-  defp tokenize_text(buffer, acc) do
-    [{:text, Enum.reverse(buffer)} | acc]
-  end
-
-  # If trim mode is enabled and the token is on a line with
-  # only itself and whitespace, trim the whitespace around it,
-  # including the line break following it if there is one.
-  defp trim_if_needed(rest, line, opts, buffer, acc) do
-    original = {rest, line, buffer}
-    if opts[:trim] do
-      case {trim_left(buffer, acc), trim_right(rest, line)} do
-        {{true, new_buffer}, {true, new_rest, new_line}} ->
-          {new_rest, new_line, new_buffer}
-        _ ->
-          original
-      end
-    else
-      original
-    end
-  end
-
-  defp trim_left(buffer, acc) do
-    case {trim_whitespace(buffer), acc} do
-      {[?\n | _] = trimmed_buffer, _} -> {true, trimmed_buffer}
-      {[], []} -> {true, []}
-      _ -> {false, buffer}
-    end
-  end
-
-  defp trim_right(rest, line) do
-    case trim_whitespace(rest) do
-      [?\r, ?\n | trimmed_rest] -> {true, trimmed_rest, line + 1}
-      [?\n | trimmed_rest] -> {true, trimmed_rest, line + 1}
-      [] -> {true, [], line}
-      _ -> {false, rest, line}
-    end
-  end
-
-  defp trim_whitespace([h | t]) when h == ?\s or h == ?\t do
-    trim_whitespace(t)
-  end
-
-  defp trim_whitespace(list) do
-    list
+  defp tokenize_text(line, buffer, acc) do
+    [{ :text, line, list_to_binary(List.reverse(buffer)) } | acc]
  end
 end
@@ -2,8 +2,6 @@ defmodule EEx.Mixfile do
  use Mix.Project

  def project do
-    [app: :eex,
-     version: System.version,
-     build_per_environment: false]
+    [app: :eex, version: System.version]
  end
-end
+end
@@ -1,45 +1,22 @@
-Code.require_file "../test_helper.exs", __DIR__
+Code.require_file "../../test_helper", __FILE__

 defmodule EEx.SmartEngineTest do
  use ExUnit.Case, async: true

-  import ExUnit.CaptureIO
-
  test "evaluates simple string" do
    assert_eval "foo bar", "foo bar"
  end

-  test "evaluates with assigns as keywords" do
+  test "evaluates with assigns" do
    assert_eval "1", "<%= @foo %>", assigns: [foo: 1]
  end

-  test "evaluates with assigns as a map" do
-    assert_eval "1", "<%= @foo %>", assigns: %{foo: 1}
-  end
-
-  test "error with missing assigns" do
-    stderr = capture_io(:stderr, fn ->
-      assert_eval "", "<%= @foo %>", assigns: %{}
-    end)
-    assert stderr =~ "assign @foo not available in EEx template"
-  end
-
  test "evaluates with loops" do
-    assert_eval "1\n2\n3\n", "<%= for x <- [1, 2, 3] do %><%= x %>\n<% end %>"
+    assert_eval "1\n2\n3\n", "<%= lc x inlist [1,2,3] do %><%= x %>\n<% end %>"
  end

-  test "compiled preserved line numbers" do
-    result = EEx.compile_string("<%= @hello %>", engine: EEx.SmartEngine)
-    Macro.prewalk(result, fn
-      {_left, meta, _right} ->
-        assert Keyword.get(meta, :line, 0) in [0, 1]
-      _ ->
-        :ok
-    end)
-  end
-
-  defp assert_eval(expected, actual, binding \\ []) do
-    result = EEx.eval_string(actual, binding, file: __ENV__.file)
+  defp assert_eval(expected, actual, binding // []) do
+    result = EEx.eval_string(actual, binding, file: __FILE__)
    assert result == expected
  end
 end
@@ -1,30 +1,27 @@
-Code.require_file "../test_helper.exs", __DIR__
+Code.require_file "../../test_helper", __FILE__

 defmodule EEx.TokenizerTest do
  use ExUnit.Case, async: true
  require EEx.Tokenizer, as: T

  test "simple chars lists" do
-    assert T.tokenize('foo', 1) == {:ok, [{:text, 'foo'}]}
+    assert T.tokenize('foo', 1) == [ { :text, 1, "foo" } ]
  end

  test "simple strings" do
-    assert T.tokenize("foo", 1) == {:ok, [{:text, 'foo'}]}
+    assert T.tokenize("foo", 1) == [ { :text, 1, "foo" } ]
  end

  test "strings with embedded code" do
-    assert T.tokenize('foo <% bar %>', 1) ==
-           {:ok, [{:text, 'foo '}, {:expr, 1, '', ' bar '}]}
+    assert T.tokenize('foo <% bar %>', 1) == [ { :text, 1, "foo " }, { :expr, 1, [], ' bar ' } ]
  end

  test "strings with embedded equals code" do
-    assert T.tokenize('foo <%= bar %>', 1) ==
-           {:ok, [{:text, 'foo '}, {:expr, 1, '=', ' bar '}]}
+    assert T.tokenize('foo <%= bar %>', 1) == [ { :text, 1, "foo " }, { :expr, 1, '=', ' bar ' } ]
  end

  test "strings with more than one line" do
-    assert T.tokenize('foo\n<%= bar %>', 1) ==
-           {:ok, [{:text, 'foo\n'}, {:expr, 2, '=', ' bar '}]}
+    assert T.tokenize('foo\n<%= bar %>', 1) == [ { :text, 1, "foo\n" },{ :expr, 2, '=', ' bar ' } ]
  end

  test "strings with more than one line and expression with more than one line" do
@@ -35,129 +32,50 @@ baz %>
 <% foo %>
 '''

-    assert T.tokenize(string, 1) == {:ok, [
-      {:text, 'foo '},
+    assert T.tokenize(string, 1) == [
+      {:text, 1, "foo "},
      {:expr, 1, '=', ' bar\n\nbaz '},
-      {:text, '\n'},
-      {:expr, 4, '', ' foo '},
-      {:text, '\n'}
-    ]}
-  end
-
-  test "quotation" do
-    assert T.tokenize('foo <%% true %>', 1) == {:ok, [
-      {:text, 'foo <% true %>'}
-    ]}
-  end
-
-  test "quotation with do/end" do
-    assert T.tokenize('foo <%% true do %>bar<%% end %>', 1) == {:ok, [
-      {:text, 'foo <% true do %>bar<% end %>'}
-    ]}
-  end
-
-  test "quotation with interpolation" do
-    assert T.tokenize('a <%% b <%= c %> <%= d %> e %> f', 1) == {:ok, [
-      {:text, 'a <% b '},
-      {:expr, 1, '=', ' c '},
-      {:text, ' '},
-      {:expr, 1, '=', ' d '},
-      {:text, ' e %> f'}
-    ]}
-
-    assert T.tokenize('<%%% a <%%= b %> c %>', 1) == {:ok, [
-      {:text, '<%% a <%= b %> c %>'}
-    ]}
-  end
-
-  test "comments" do
-    assert T.tokenize('foo <%# true %>', 1) == {:ok, [
-      {:text, 'foo '}
-    ]}
-  end
-
-  test "comments with do/end" do
-    assert T.tokenize('foo <%# true do %>bar<%# end %>', 1) == {:ok, [
-      {:text, 'foo bar'}
-    ]}
+      {:text, 3, "\n"},
+      {:expr, 4, [], ' foo '},
+      {:text, 4, "\n"}
+    ] 
  end

  test "strings with embedded do end" do
-    assert T.tokenize('foo <% if true do %>bar<% end %>', 1) == {:ok, [
-      {:text, 'foo '},
-      {:start_expr, 1, '', ' if true do '},
-      {:text, 'bar'},
-      {:end_expr, 1, '', ' end '}
-    ]}
+    assert T.tokenize('foo <% if true do %>bar<% end %>', 1) == [
+      { :text, 1, "foo " },
+      { :start_expr, 1, '', ' if true do ' },
+      { :text, 1, "bar" },
+      { :end_expr, 1, '', ' end ' }
+    ]
  end

  test "strings with embedded -> end" do
-    assert T.tokenize('foo <% cond do %><% false -> %>bar<% true -> %>baz<% end %>', 1) == {:ok, [
-      {:text, 'foo '},
-      {:start_expr, 1, '', ' cond do '},
-      {:middle_expr, 1, '', ' false -> '},
-      {:text, 'bar'},
-      {:middle_expr, 1, '', ' true -> '},
-      {:text, 'baz'},
-      {:end_expr, 1, '', ' end '}
-    ]}
+    assert T.tokenize('foo <% cond do %><% false -> %>bar<% true -> %>baz<% end %>', 1) == [
+      { :text, 1, "foo " },
+      { :start_expr, 1, '', ' cond do ' },
+      { :middle_expr, 1, '', ' false -> ' },
+      { :text, 1, "bar" },
+      { :middle_expr, 1, '', ' true -> ' },
+      { :text, 1, "baz" },
+      { :end_expr, 1, '', ' end ' }
+    ]
  end

  test "strings with embedded keywords blocks" do
-    assert T.tokenize('foo <% if true do %>bar<% else %>baz<% end %>', 1) == {:ok, [
-      {:text, 'foo '},
-      {:start_expr, 1, '', ' if true do '},
-      {:text, 'bar'},
-      {:middle_expr, 1, '', ' else '},
-      {:text, 'baz'},
-      {:end_expr, 1, '', ' end '}
-    ]}
-  end
-
-  test "trim mode" do
-    template = '\t<%= if true do %> \n TRUE \n  <% else %>\n FALSE \n  <% end %>  '
-    assert T.tokenize(template, 1, trim: true) == {:ok, [
-      {:start_expr, 1, '=', ' if true do '},
-      {:text, ' TRUE \n'},
-      {:middle_expr, 3, '', ' else '},
-      {:text, ' FALSE \n'},
-      {:end_expr, 5, '', ' end '}
-    ]}
-  end
-
-  test "trim mode with comment" do
-    assert T.tokenize('  <%# comment %>  \n123', 1, trim: true) == {:ok, [
-      {:text, '123'}
-    ]}
-  end
-
-  test "trim mode with CRLF" do
-    assert T.tokenize('0\r\n  <%= 12 %>  \r\n34', 1, trim: true) == {:ok, [
-      {:text, '0\r\n'},
-      {:expr, 2, '=', ' 12 '},
-      {:text, '34'}
-    ]}
-  end
-
-  test "trim mode set to false" do
-    assert T.tokenize(' <%= 12 %> \n', 1, trim: false) == {:ok, [
-      {:text, ' '},
-      {:expr, 1, '=', ' 12 '},
-      {:text, ' \n'}
-    ]}
-  end
-
-  test "trim mode no false positives" do
-    assert_not_trimmed = fn x -> assert T.tokenize(x, 1, trim: true) == T.tokenize(x, 1) end
-
-    assert_not_trimmed.('foo <%= "bar" %>  ')
-    assert_not_trimmed.('\n  <%= "foo" %>bar')
-    assert_not_trimmed.('  <%% hello %>  ')
-    assert_not_trimmed.('  <%= 01 %><%= 23 %>\n')
+    assert T.tokenize('foo <% if true do %>bar<% else %>baz<% end %>', 1) == [
+      { :text, 1, "foo " },
+      { :start_expr, 1, '', ' if true do ' },
+      { :text, 1, "bar" },
+      { :middle_expr, 1, '', ' else ' },
+      { :text, 1, "baz" },
+      { :end_expr, 1, '', ' end ' }
+    ]
  end

  test "raise syntax error when there is start mark and no end mark" do
-    assert T.tokenize('foo <% :bar', 1) == {:error, 1, "missing token '%>'"}
-    assert T.tokenize('<%# true ', 1) == {:error, 1, "missing token '%>'"}
+    assert_raise EEx.SyntaxError, "missing token: %>", fn ->
+      T.tokenize('foo <% :bar', 1)
+    end
  end
 end
@@ -1,39 +1,41 @@
-Code.require_file "test_helper.exs", __DIR__
+Code.require_file "../test_helper", __FILE__

 require EEx

-defmodule EExTest.Compiled do
+defmodule EExText.Compiled do
  def before_compile do
-    fill_in_stacktrace()
-    {__ENV__.line, hd(tl(System.stacktrace))}
+    fill_in_stacktrace
+    { __ENV__.line, hd(tl(System.stacktrace)) }
  end
-
+  { :erlang, 1, 2 }.tuple_to_list
  EEx.function_from_string :def, :string_sample, "<%= a + b %>", [:a, :b]

-  filename = Path.join(__DIR__, "fixtures/eex_template_with_bindings.eex")
+  filename = File.expand_path("../fixtures/eex_template_with_bindings.eex", __FILE__)
  EEx.function_from_file :defp, :private_file_sample, filename, [:bar]
-
-  filename = Path.join(__DIR__, "fixtures/eex_template_with_bindings.eex")
-  EEx.function_from_file :def, :public_file_sample, filename, [:bar]
-
  def file_sample(arg), do: private_file_sample(arg)

  def after_compile do
-    fill_in_stacktrace()
-    {__ENV__.line, hd(tl(System.stacktrace))}
+    fill_in_stacktrace
+    { __ENV__.line, hd(tl(System.stacktrace)) }
  end

  @file "unknown"
  def unknown do
-    fill_in_stacktrace()
-    {__ENV__.line, hd(tl(System.stacktrace))}
+    fill_in_stacktrace
+    { __ENV__.line, hd(tl(System.stacktrace)) }
+  end
+
+  @file __ENV__
+  def other do
+    fill_in_stacktrace
+    { __ENV__.line, hd(tl(System.stacktrace)) }
  end

  defp fill_in_stacktrace do
    try do
-      :erlang.error "failed"
+      Erlang.erlang.error "failed"
    catch
-      :error, _ -> System.stacktrace
+      :error, _, stack -> stack
    end
  end
 end
@@ -49,10 +51,6 @@ end
 defmodule EExTest do
  use ExUnit.Case, async: true

-  doctest EEx
-  doctest EEx.Engine
-  doctest EEx.SmartEngine
-
  test "evaluates simple string" do
    assert_eval "foo bar", "foo bar"
  end
@@ -98,16 +96,12 @@ defmodule EExTest do
    assert_eval "foo baz", "foo <%= if true do %><%= if false do %>bar<% else %>baz<% end %><% end %>"
  end

-  test "evaluates with parentheses after end in end token" do
-    assert_eval " 101  102  103 ", "<%= Enum.map([1, 2, 3], (fn x -> %> <%= 100 + x %> <% end) ) %>"
-  end
-
  test "evaluates with defined variable" do
    assert_eval "foo 1", "foo <% bar = 1 %><%= bar %>"
  end

  test "evaluates with require code" do
-    assert_eval "foo 1,2,3", "foo <% require Enum, as: E %><%= E.join [1, 2, 3], \",\" %>"
+    assert_eval "foo 1,2,3", "foo <% require Enum, as: E %><%= E.join [1,2,3], \",\" %>"
  end

  test "evaluates with end of token" do
@@ -115,25 +109,25 @@ defmodule EExTest do
  end

  test "raises a syntax error when the token is invalid" do
-    assert_raise EEx.SyntaxError, "nofile:1: missing token '%>'", fn ->
+    assert_raise EEx.SyntaxError, "missing token: %>", fn ->
      EEx.compile_string "foo <%= bar"
    end
  end

  test "raises a syntax error when end expression is found without a start expression" do
-    assert_raise EEx.SyntaxError, "nofile:1: unexpected token ' end '",  fn ->
+    assert_raise EEx.SyntaxError, "unexpected token: ' end ' at line 1",  fn ->
      EEx.compile_string "foo <% end %>"
    end
  end

  test "raises a syntax error when start expression is found without an end expression" do
-    assert_raise EEx.SyntaxError, "nofile:2: unexpected end of string, expected a closing '<% end %>'", fn ->
-      EEx.compile_string "foo\n<% if true do %>"
+    assert_raise EEx.SyntaxError, "unexpected end of string. expecting a closing <% end %>.", fn ->
+      EEx.compile_string "foo <% if true do %>"
    end
  end

-  test "raises a syntax error when nested end expression is found without a start expression" do
-    assert_raise EEx.SyntaxError, "nofile:1: unexpected token ' end '", fn ->
+  test "raises a syntax error when nested end expression is found without an start expression" do
+    assert_raise EEx.SyntaxError, "unexpected token: ' end ' at line 1", fn ->
      EEx.compile_string "foo <% if true do %><% end %><% end %>"
    end
  end
@@ -236,10 +230,6 @@ foo
    assert_eval expected, string
  end

-  test "respects files" do
-    assert_eval "sample.ex", "<%= __ENV__.file %>", [], file: "sample.ex"
-  end
-
  test "properly handle functions" do
    expected = """

@@ -252,7 +242,7 @@ Number 3
 """

    string = """
-<%= Enum.map [1, 2, 3], fn x -> %>
+<%= Enum.map [1,2,3], fn x -> %>
 Number <%= x %>
 <% end %>
 """
@@ -260,7 +250,7 @@ Number <%= x %>
    assert_eval expected, string
  end

-  test "properly handle functions on the left side of clauses" do
+  test "do not consider already finished functions" do
    expected = """
 foo

@@ -280,159 +270,73 @@ foo
    assert_eval expected, string
  end

-  test "evaluates nested do expressions" do
-    string = """
-    <% y = ["a", "b", "c"] %>
-    <%= cond do %>
-     <% "a" in y -> %>
-      Good
-     <% true -> %>
-      <% if true do %>true<% else %>false<% end %>
-      Bad
-    <% end %>
-    """
-
-    assert_eval "\n\n  Good\n \n", string
-  end
-
-  test "evaluates expressions with buffers" do
-    string = """
-    <%= 123 %>
-    <% if true do %>
-      <%= 456 %>
-    <% end %>
-    <%= 789 %>
-    """
-
-    assert_eval "123\n\n789\n", string
-  end
-
-  test "for comprehensions" do
-    string = """
-    <%= for _name <- packages || [] do %>
-    <% end %>
-    <%= all || :done %>
-    """
-    assert_eval "\ndone\n", string, packages: nil, all: nil
-  end
-
-  test "Unicode" do
-    template = """
-      • <%= "•" %> •
-      <%= "Jößé Vâlìm" %> Jößé Vâlìm
-    """
-    result = EEx.eval_string(template)
-    assert result == "  • • •\n  Jößé Vâlìm Jößé Vâlìm\n"
-  end
-
-  test "trim mode" do
-    string = "<%= 123 %> \n456\n  <%= 789 %>"
-    expected = "123456\n789"
-    assert_eval expected, string, [], trim: true
-  end
-
-  test "trim mode with middle expression" do
-    string = """
-    <%= cond do %>
-    <% false -> %>
-      this
-    <% true -> %>
-      that
-    <% end %>
-    """
-    expected = "  that\n"
-    assert_eval expected, string, [], trim: true
-  end
-
  test "evaluates the source from a given file" do
-    filename = Path.join(__DIR__, "fixtures/eex_template.eex")
+    filename = File.expand_path("../fixtures/eex_template.eex", __FILE__)
    result = EEx.eval_file(filename)
    assert result == "foo bar.\n"
  end

  test "evaluates the source from a given file with bindings" do
-    filename = Path.join(__DIR__, "fixtures/eex_template_with_bindings.eex")
+    filename = File.expand_path("../fixtures/eex_template_with_bindings.eex", __FILE__)
    result = EEx.eval_file(filename, [bar: 1])
    assert result == "foo 1\n"
  end

  test "raises an Exception when there's an error with the given file" do
-    assert_raise File.Error, "could not read file \"non-existent.eex\": no such file or directory", fn ->
+    assert_raise File.Error, "could not read file non-existent.eex: no such file or directory", fn ->
      filename = "non-existent.eex"
      EEx.compile_file(filename)
    end
  end

-  test "sets external resource attribute" do
-    assert EExTest.Compiled.__info__(:attributes)[:external_resource] ==
-           [Path.join(__DIR__, "fixtures/eex_template_with_bindings.eex")]
-  end
-
  test "defined from string" do
-    assert EExTest.Compiled.string_sample(1, 2) == "3"
+    assert EExText.Compiled.string_sample(1, 2) == "3"
  end

  test "defined from file" do
-    assert EExTest.Compiled.file_sample(1) == "foo 1\n"
-    assert EExTest.Compiled.public_file_sample(1) == "foo 1\n"
+    assert EExText.Compiled.file_sample(1) == "foo 1\n"
  end

  test "defined from file do not affect backtrace" do
-    assert EExTest.Compiled.before_compile ==
-      {8,
-        {EExTest.Compiled,
+    assert EExText.Compiled.before_compile ==
+      { 8,
+        { EExText.Compiled,
          :before_compile,
          0,
-          [file: to_charlist(Path.relative_to_cwd(__ENV__.file)), line: 7]
-       }
-     }
+          [file: binary_to_list(__FILE__), line: 7]
+        }
+      }

-    assert EExTest.Compiled.after_compile ==
-      {23,
-        {EExTest.Compiled,
+    assert EExText.Compiled.after_compile ==
+      { 19,
+        { EExText.Compiled,
          :after_compile,
          0,
-          [file: to_charlist(Path.relative_to_cwd(__ENV__.file)), line: 22]
-       }
-     }
+          [file: binary_to_list(__FILE__), line: 18]
+        }
+      }

-    assert EExTest.Compiled.unknown ==
-      {29,
-        {EExTest.Compiled,
+    assert EExText.Compiled.unknown ==
+      { 25,
+        { EExText.Compiled,
          :unknown,
          0,
-          [file: 'unknown', line: 28]
-       }
-     }
+          [file: 'unknown', line: 24]
+        }
+      }
+
+    assert EExText.Compiled.other ==
+      { 31,
+        { EExText.Compiled,
+          :other,
+          0,
+          [file: binary_to_list(__FILE__), line: 30]
+        }
+      }
  end

-  defmodule TestEngine do
-    @behaviour EEx.Engine
-
-    def init(_opts) do
-      ""
-    end
-
-    def handle_body(body) do
-      {:wrapped, body}
-    end
-
-    def handle_text(buffer, text) do
-      EEx.Engine.handle_text(buffer, text)
-    end
-
-    def handle_expr(buffer, mark, expr) do
-      EEx.Engine.handle_expr(buffer, mark, expr)
-    end
-  end
-
-  test "calls handle_body" do
-    assert {:wrapped, "foo"} = EEx.eval_string("foo", [], engine: TestEngine)
-  end
-
-  defp assert_eval(expected, actual, binding \\ [], opts \\ []) do
-    opts = Enum.into [file: __ENV__.file, engine: EEx.Engine], opts
-    result = EEx.eval_string(actual, binding, opts)
+  defp assert_eval(expected, actual) do
+    result = EEx.eval_string(actual, [], file: __FILE__, engine: EEx.Engine)
    assert result == expected
  end
 end
@@ -1 +1,2 @@
-ExUnit.start [trace: "--trace" in System.argv]
+# Configure ExUnit, no options supported yet.
+ExUnit.start []
@@ -0,0 +1,39 @@
+-define(ELIXIR_WRAP_CALL(Line, Module, Function, Args),
+  { call, Line,
+    { remote, Line, { atom, Line, Module }, { atom, Line, Function } },
+    Args
+  }).
+
+-define(ELIXIR_ATOM_CONCAT(Atoms), list_to_atom(lists:concat(Atoms))).
+-define(ELIXIR_MACRO(Macro), list_to_atom(lists:concat(['MACRO-',Macro]))).
+
+-record(elixir_scope, {
+  context=nil,                                   %% can be assign, guards or nil
+  noname=false,                                  %% when true, don't add new names (used by try)
+  check_clauses=true,                            %% when true, check def clauses ordering
+  super=false,                                   %% when true, it means super was invoked
+  caller=false,                                  %% when true, it means caller was invoked
+  name_args=false,                               %% when true, it means arguments should be named
+  macro=[],                                      %% a stack with macros nesting
+  module=nil,                                    %% the current module
+  function=nil,                                  %% the current function
+  recur=nil,                                     %% the current loop function to be recurred
+  vars=dict:new(),                               %% a dict of defined variables and their alias
+  temp_vars=dict:new(),                          %% a dict of all variables defined in a particular assign
+  clause_vars=dict:new(),                        %% a dict of all variables defined in a particular clause
+  quote_vars=dict:new(),                         %% a dict of all quoted variables
+  extra_guards=nil,                              %% extra guards from args expansion
+  counter=0,                                     %% a counter for the variables defined
+  file=(<<"nofile">>),                           %% the current scope filename
+  local=nil,                                     %% the scope to evaluate local functions against
+  aliases=[],                                    %% an orddict with aliases by new -> old names
+  requires=elixir_dispatch:default_requires(),   %% a set with modules required
+  macros=elixir_dispatch:default_macros(),       %% a list with macros imported by module
+  functions=elixir_dispatch:default_functions(), %% a list with functions imported by module
+  scheduled=[]}).                                %% scheduled modules to be loaded
+
+-record(elixir_quote, {
+  line=0,
+  marker=quoted,
+  unquote=true
+}).
@@ -1,656 +1,66 @@
-defmodule Access do
+import Kernel, except: [access: 2]
+
+defprotocol Access do
  @moduledoc """
-  Key-based access to data structures using the `data[key]` syntax.
-
-  Elixir provides two syntaxes for accessing values. `user[:name]`
-  is used by dynamic structures, like maps and keywords, while
-  `user.name` is used by structs. The main difference is that
-  `user[:name]` won't raise if the key `:name` is missing but
-  `user.name` will raise if there is no `:name` key.
-
-  Besides the cases above, this module provides convenience
-  functions for accessing other structures, like `at/1` for
-  lists and `elem/1` for tuples. Those functions can be used
-  by the nested update functions in `Kernel`, such as
-  `Kernel.get_in/2`, `Kernel.put_in/3`, `Kernel.update_in/3`,
-  `Kernel.get_and_update_in/3` and friends.
-
-  ## Dynamic lookups
-
-  Out of the box, `Access` works with `Keyword` and `Map`:
-
-      iex> keywords = [a: 1, b: 2]
-      iex> keywords[:a]
-      1
-
-      iex> map = %{a: 1, b: 2}
-      iex> map[:a]
-      1
-
-      iex> star_ratings = %{1.0 => "★", 1.5 => "★☆", 2.0 => "★★"}
-      iex> star_ratings[1.5]
-      "★☆"
-
-  Note that the dynamic lookup syntax (`term[key]`) roughly translates to
-  `Access.get(term, key, nil)`.
-
-  `Access` can be combined with `Kernel.put_in/3` to put a value
-  in a given key:
-
-      iex> map = %{a: 1, b: 2}
-      iex> put_in map[:a], 3
-      %{a: 3, b: 2}
-
-  This syntax is very convenient as it can be nested arbitrarily:
-
-      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
-      iex> put_in users["john"][:age], 28
-      %{"john" => %{age: 28}, "meg" => %{age: 23}}
-
-  Furthermore, `Access` transparently ignores `nil` values:
-
-      iex> keywords = [a: 1, b: 2]
-      iex> keywords[:c][:unknown]
-      nil
-
-  Since `Access` is a behaviour, it can be implemented for key-value
-  data structures. The implementation should be added to the
-  module that defines the struct being accessed. `Access` requires the
-  key comparison to be implemented using the `===` operator.
-
-  ## Static lookups
-
-  The `Access` syntax (`foo[bar]`) cannot be used to access fields in
-  structs, since structs do not implement the `Access` behaviour by
-  default. It is also a design decision: the dynamic access lookup
-  is meant to be used for dynamic key-value structures, like maps
-  and keywords, and not by static ones like structs (where fields are
-  known and not dynamic).
-
-  Therefore Elixir provides a static lookup for struct fields and for atom
-  fields in maps. Imagine a struct named `User` with a `:name` field.
-  The following would raise:
-
-      user = %User{name: "John"}
-      user[:name]
-      # ** (UndefinedFunctionError) undefined function User.fetch/2
-      #    (User does not implement the Access behaviour)
-
-  Structs instead use the `user.name` syntax to access fields:
-
-      user.name
-      #=> "John"
-
-  The same `user.name` syntax can also be used by `Kernel.put_in/2`
-  to for updating structs fields:
-
-      put_in user.name, "Mary"
-      #=> %User{name: "Mary"}
-
-  Differently from `user[:name]`, `user.name` is not extensible via
-  a behaviour and is restricted only to structs and atom keys in maps.
-
-  As mentioned above, this works for atom keys in maps as well. Refer to the
-  `Map` module for more information on this.
-
-  Summing up:
-
-    * `user[:name]` is used by dynamic structures, is extensible and
-      does not raise on missing keys
-    * `user.name` is used by static structures, it is not extensible
-      and it will raise on missing keys
-
-  ## Accessors
-
-  While Elixir provides built-in syntax only for traversing dynamic
-  and static key-value structures, this module provides convenience
-  functions for traversing other structures, like tuples and lists,
-  to be used alongside `Kernel.put_in/2` in others.
-
-  For instance, given a user with a list of languages, here is how to
-  deeply traverse the map and convert all language names to uppercase:
-
-      iex> user = %{name: "john",
-      ...>          languages: [%{name: "elixir", type: :functional},
-      ...>                      %{name: "c", type: :procedural}]}
-      iex> update_in user, [:languages, Access.all(), :name], &String.upcase/1
-      %{name: "john",
-        languages: [%{name: "ELIXIR", type: :functional},
-                    %{name: "C", type: :procedural}]}
-
-  See the functions `key/1`, `key!/1`, `elem/1`, and `all/0` for some of the
-  available accessors.
-
-  ## Implementing the Access behaviour for custom data structures
-
-  In order to be able to use the `Access` protocol with custom data structures
-  (which have to be structs), such structures have to implement the `Access`
-  behaviour. For example, for a `User` struct, this would have to be done:
-
-      defmodule User do
-        defstruct [:name, :email]
-
-        @behaviour Access
-        # Implementation of the Access callbacks...
-      end
+  The Access protocol is the underlying protocol invoked
+  when the brackets syntax is used. For instance, `foo[bar]`
+  is translated to `access foo, bar` which, by default,
+  invokes `Access.access` protocol.

+  This protocol is limited and is implemented only for the
+  following built-in types: keywords, tuples, atoms and
+  functions.
  """

-  @type t :: list | map | nil | any
-  @type key :: any
-  @type value :: any
+  @only [List, Function, Record, Atom]

  @doc """
-  Invoked in order to access the value stored under `key` in the given term `term`.
-
-  This function should return `{:ok, value}` where `value` is the value under
-  `key` if it succeeded, or `:error` if the key does not exist in the structure.
-
-  Many of the functions defined in the `Access` module internally call this
-  function. This function is also used when the square-brackets access syntax
-  (`structure[key]`) is used: the `fetch/2` callback implemented by the module
-  that defines the `structure` struct is invoked and if it returns `{:ok,
-  value}` then `value` is returned, or if it returns `:error` then `nil` is
-  returned.
-
-
-  See the `Map.fetch/2` and `Keyword.fetch/2` implementations for examples of
-  how to implement this callback.
+  Receives the element being accessed and the access item.
  """
-  @callback fetch(term :: t, key) :: {:ok, value} | :error
+  def access(element, qualifier)
+end

+defimpl Access, for: List do
  @doc """
-  Invoked in order to access the value stored under `key` in the given term `term`,
-  defaulting to `default` if not present.
-
-  This function should return the value under the key `key` in `term` if there's
-  such key, otherwise `default`.
-
-  For most data structures, this can be implemented using `fetch/2` internally;
-  for example:
-
-      def get(structure, key, default) do
-        case fetch(structure, key) do
-          {:ok, value} -> value
-          :error       -> default
-        end
-      end
-
-  See the `Map.get/3` and `Keyword.get/3` implementations for more examples.
-  """
-  @callback get(term :: t, key, default :: value) :: value
-
-  @doc """
-  Invoked in order to access the value under `key` and update it at the same time.
-
-  The implementation of this callback should invoke the passed function with the
-  value under key `key` in the passed structure, or `nil` if the key is not
-  present. This function should return either `{value_to_return, new_value}` or
-  `:pop`.
-
-  If it returns `{value_to_return, new_value}`, the return value of this
-  callback should be `{value_to_return, new_term}` where `new_term` is `term`
-  after updating the value of `key` with `new_value`.
-
-  If it returns `:pop`, the return value of this callback should be `{value,
-  new_term}` where `value` is the value under `key` or `nil` if not present, and
-  `new_term` is `term` without the key `key`.
-
-  See the implementations of `Map.get_and_update/3` or `Keyword.get_and_update/3`
-  for more examples.
-  """
-  @callback get_and_update(term :: t, key, (value -> {value, value} | :pop)) :: {value, t}
-
-  @doc """
-  Invoked to "pop" the value under `key` out of the given term.
-
-  When the key `key` exists in the given `term`, the implementation should
-  return a `{value, new_term}` tuple where `value` is the value that was under
-  `key` and `new_term` is `term` without `key`.
-
-  When the key `key` is not present in the given `term`, a tuple `{value, term}`
-  should be returned, where `value` is implementation-defined.
-
-  See the implementations for `Map.pop/3` or `Keyword.pop/3` for more examples.
-  """
-  @callback pop(term :: t, key) :: {value, t}
-
-  defmacrop raise_undefined_behaviour(e, struct, top) do
-    quote do
-      stacktrace = System.stacktrace
-      e =
-        case stacktrace do
-          [unquote(top) | _] ->
-            %{unquote(e) | reason: "#{inspect unquote(struct)} does not implement the Access behaviour"}
-          _ ->
-            unquote(e)
-        end
-      reraise e, stacktrace
-    end
-  end
-
-  @doc """
-  Fetches the value for the given key in a container (a map, keyword
-  list, or struct that implements the `Access` behaviour).
-  """
-  @spec fetch(t, term) :: {:ok, term} | :error
-  def fetch(container, key)
-
-  def fetch(%{__struct__: struct} = container, key) do
-    struct.fetch(container, key)
-  rescue
-    e in UndefinedFunctionError ->
-      raise_undefined_behaviour e, struct, {^struct, :fetch, [^container, ^key], _}
-  end
-
-  def fetch(map, key) when is_map(map) do
-    Map.fetch(map, key)
-  end
-
-  def fetch(list, key) when is_list(list) and is_atom(key) do
-    Keyword.fetch(list, key)
-  end
-
-  def fetch(list, key) when is_list(list) do
-    raise ArgumentError,
-      "the Access calls for keywords expect the key to be an atom, got: " <> inspect(key)
-  end
-
-  def fetch(nil, _key) do
-    :error
-  end
-
-  @doc """
-  Gets the value for the given key in a container (a map, keyword
-  list, or struct that implements the `Access` behaviour).
-  """
-  @spec get(t, term, term) :: term
-  def get(container, key, default \\ nil) do
-    case fetch(container, key) do
-      {:ok, value} -> value
-      :error -> default
-    end
-  end
-
-  @doc """
-  Gets and updates the given key in a container (a map, keyword
-  list, or struct that implements the `Access` behaviour).
-
-  This `fun` argument receives the value of `key` (or `nil` if `key`
-  is not present) and must return a two-element tuple: the "get" value
-  (the retrieved value, which can be operated on before being returned)
-  and the new value to be stored under `key`. The `fun` may also
-  return `:pop`, implying the current value shall be removed
-  from the container and returned.
-
-  The returned value is a two-element tuple with the "get" value returned by
-  `fun` and a new container with the updated value under `key`.
-  """
-  @spec get_and_update(container :: t, key, (value -> {get_value, update_value} | :pop)) ::
-        {get_value, container :: t} when get_value: var, update_value: value
-  def get_and_update(container, key, fun)
-
-  def get_and_update(%{__struct__: struct} = container, key, fun) do
-    struct.get_and_update(container, key, fun)
-  rescue
-    e in UndefinedFunctionError ->
-      raise_undefined_behaviour e, struct, {^struct, :get_and_update, [^container, ^key, ^fun], _}
-  end
-
-  def get_and_update(map, key, fun) when is_map(map) do
-    Map.get_and_update(map, key, fun)
-  end
-
-  def get_and_update(list, key, fun) when is_list(list) do
-    Keyword.get_and_update(list, key, fun)
-  end
-
-  def get_and_update(nil, key, _fun) do
-    raise ArgumentError,
-      "could not put/update key #{inspect key} on a nil value"
-  end
-
-  @doc """
-  Removes the entry with a given key from a container (a map, keyword
-  list, or struct that implements the `Access` behaviour).
-
-  Returns a tuple containing the value associated with the key and the
-  updated container. `nil` is returned for the value if the key isn't
-  in the container.
+  Access the given key in a keywords list.

  ## Examples

-  With a map:
-
-      iex> Access.pop(%{name: "Elixir", creator: "Valim"}, :name)
-      {"Elixir", %{creator: "Valim"}}
-
-  A keyword list:
-
-      iex> Access.pop([name: "Elixir", creator: "Valim"], :name)
-      {"Elixir", [creator: "Valim"]}
-
-  An unknown key:
-
-      iex> Access.pop(%{name: "Elixir", creator: "Valim"}, :year)
-      {nil, %{creator: "Valim", name: "Elixir"}}
+      keywords = [a: 1, b: 2]
+      keywords[:a] #=> 1

  """
-  def pop(%{__struct__: struct} = container, key) do
-    struct.pop(container, key)
-  rescue
-    e in UndefinedFunctionError ->
-      raise_undefined_behaviour e, struct, {^struct, :pop, [^container, ^key], _}
+
+  def access(list, atom) when is_atom(atom) do
+    atom_access(list, atom)
  end

-  def pop(map, key) when is_map(map) do
-    Map.pop(map, key)
-  end
-
-  def pop(list, key) when is_list(list) do
-    Keyword.pop(list, key)
-  end
-
-  def pop(nil, key) do
-    raise ArgumentError,
-      "could not pop key #{inspect key} on a nil value"
-  end
-
-  ## Accessors
-
-  @doc false
-  def key(key) do
-    IO.warn "Access.key/1 is deprecated due to erratic behaviour for missing keys, " <>
-            "please use Access.key/2 instead with proper default values " <>
-            "(or Access.key!/1 if you expect the key to always be available)"
-
-    fn
-      :get, data, next ->
-        next.(Map.get(to_map(data), key))
-      :get_and_update, data, next ->
-        value = Map.get(to_map(data), key)
-        case next.(value) do
-          {get, update} -> {get, Map.put(data, key, update)}
-          :pop -> {value, Map.delete(data, key)}
-        end
-    end
-  end
-
-  defp to_map(nil), do: %{}
-  defp to_map(%{} = map), do: map
-  defp to_map(data), do: raise "Access.key/1 expected a map/struct or nil, got: #{inspect data}"
+  defp atom_access([{k, _}|_], key) when key < k, do: nil
+  defp atom_access([{k, _}|d], key) when key > k, do: atom_access(d, key)
+  defp atom_access([{_k, value}|_], _key),        do: value
+  defp atom_access([], _),                        do: nil
+end

+defimpl Access, for: Atom do
  @doc """
-  Returns a function that accesses the given key in a map/struct.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  The returned function uses the default value if the key does not exist.
-  This can be used to specify defaults and safely traverse missing keys:
-
-      iex> get_in(%{}, [Access.key(:user, %{}), Access.key(:name, nil)])
-      nil
-
-  Such is also useful when using update functions, allowing us to introduce
-  values as we traverse the data-structure for updates:
-
-      iex> put_in(%{}, [Access.key(:user, %{}), Access.key(:name, nil)], "Mary")
-      %{user: %{name: "Mary"}}
-
-  ## Examples
-
-      iex> map = %{user: %{name: "john"}}
-      iex> get_in(map, [Access.key(:unknown, %{}), Access.key(:name, "john")])
-      "john"
-      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: %{name: "JOHN"}}}
-      iex> pop_in(map, [Access.key!(:user), Access.key!(:name)])
-      {"john", %{user: %{}}}
-
-  An error is raised if the accessed structure is not a map or a struct:
-
-      iex> get_in(nil, [Access.key(:foo, nil)])
-      ** (BadMapError) expected a map, got: nil
-
-      iex> get_in([], [Access.key(:foo, nil)])
-      ** (BadMapError) expected a map, got: []
-
+  The access protocol can only be accessed by atoms
+  at compilation time. If we reach this, we should raise
+  an exception.
  """
-  def key(key, default) do
-    fn
-      :get, data, next ->
-        next.(Map.get(data, key, default))
-      :get_and_update, data, next ->
-        value = Map.get(data, key, default)
-        case next.(value) do
-          {get, update} -> {get, Map.put(data, key, update)}
-          :pop -> {value, Map.delete(data, key)}
-        end
-    end
+  def access(atom, _) do
+    raise "The access protocol can only be invoked for atoms at " <>
+      "compilation time, tried to invoke it for #{inspect atom}"
  end
+end

+defimpl Access, for: Function do
  @doc """
-  Returns a function that accesses the given key in a map/struct.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  Raises if the key does not exist.
-
-  ## Examples
-
-      iex> map = %{user: %{name: "john"}}
-      iex> get_in(map, [Access.key!(:user), Access.key!(:name)])
-      "john"
-      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: %{name: "JOHN"}}}
-      iex> pop_in(map, [Access.key!(:user), Access.key!(:name)])
-      {"john", %{user: %{}}}
-      iex> get_in(map, [Access.key!(:user), Access.key!(:unknown)])
-      ** (KeyError) key :unknown not found in: %{name: \"john\"}
-
-  An error is raised if the accessed structure is not a map/struct:
-
-      iex> get_in([], [Access.key!(:foo)])
-      ** (RuntimeError) Access.key!/1 expected a map/struct, got: []
-
-  """
-  def key!(key) do
-    fn
-      :get, %{} = data, next ->
-        next.(Map.fetch!(data, key))
-      :get_and_update, %{} = data, next ->
-        value = Map.fetch!(data, key)
-        case next.(value) do
-          {get, update} -> {get, Map.put(data, key, update)}
-          :pop -> {value, Map.delete(data, key)}
-        end
-      _op, data, _next ->
-        raise "Access.key!/1 expected a map/struct, got: #{inspect data}"
-    end
-  end
-
-  @doc ~S"""
-  Returns a function that accesses the element at the given index in a tuple.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  Raises if the index is out of bounds.
-
-  ## Examples
-
-      iex> map = %{user: {"john", 27}}
-      iex> get_in(map, [:user, Access.elem(0)])
-      "john"
-      iex> get_and_update_in(map, [:user, Access.elem(0)], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: {"JOHN", 27}}}
-      iex> pop_in(map, [:user, Access.elem(0)])
-      ** (RuntimeError) cannot pop data from a tuple
-
-  An error is raised if the accessed structure is not a tuple:
-
-      iex> get_in(%{}, [Access.elem(0)])
-      ** (RuntimeError) Access.elem/1 expected a tuple, got: %{}
-
+  The Access protocol for functions simply invokes
+  the function passing the item as argument. This
+  is useful because it allows a function to be
+  passed as argument in places a dict would also fit.
  """
-  def elem(index) when is_integer(index) do
-    pos = index + 1
-
-    fn
-      :get, data, next when is_tuple(data) ->
-        next.(:erlang.element(pos, data))
-      :get_and_update, data, next when is_tuple(data) ->
-        value = :erlang.element(pos, data)
-        case next.(value) do
-          {get, update} -> {get, :erlang.setelement(pos, data, update)}
-          :pop -> raise "cannot pop data from a tuple"
-        end
-      _op, data, _next ->
-        raise "Access.elem/1 expected a tuple, got: #{inspect data}"
-    end
-  end
-
-  @doc ~S"""
-  Returns a function that accesses all the elements in a list.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  ## Examples
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.all(), :name])
-      ["john", "mary"]
-      iex> get_and_update_in(list, [Access.all(), :name], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {["john", "mary"], [%{name: "JOHN"}, %{name: "MARY"}]}
-      iex> pop_in(list, [Access.all(), :name])
-      {["john", "mary"], [%{}, %{}]}
-
-  Here is an example that traverses the list dropping even
-  numbers and multipling odd numbers by 2:
-
-      iex> require Integer
-      iex> get_and_update_in([1, 2, 3, 4, 5], [Access.all], fn
-      ...>   num -> if Integer.is_even(num), do: :pop, else: {num, num * 2}
-      ...> end)
-      {[1, 2, 3, 4, 5], [2, 6, 10]}
-
-  An error is raised if the accessed structure is not a list:
-
-      iex> get_in(%{}, [Access.all()])
-      ** (RuntimeError) Access.all/0 expected a list, got: %{}
-
-  """
-  def all() do
-    &all/3
-  end
-
-  defp all(:get, data, next) when is_list(data) do
-    Enum.map(data, next)
-  end
-
-  defp all(:get_and_update, data, next) when is_list(data) do
-    all(data, next, [], [])
-  end
-
-  defp all(_op, data, _next) do
-    raise "Access.all/0 expected a list, got: #{inspect data}"
-  end
-
-  defp all([head | rest], next, gets, updates) do
-    case next.(head) do
-      {get, update} -> all(rest, next, [get | gets], [update | updates])
-      :pop -> all(rest, next, [head | gets], updates)
-    end
-  end
-
-  defp all([], _next, gets, updates) do
-    {:lists.reverse(gets), :lists.reverse(updates)}
-  end
-
-  @doc ~S"""
-  Returns a function that accesses the element at `index` (zero based) of a list.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  ## Examples
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.at(1), :name])
-      "mary"
-      iex> get_and_update_in(list, [Access.at(0), :name], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {"john", [%{name: "JOHN"}, %{name: "mary"}]}
-
-  `at/1` can also be used to pop elements out of a list or
-  a key inside of a list:
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> pop_in(list, [Access.at(0)])
-      {%{name: "john"}, [%{name: "mary"}]}
-      iex> pop_in(list, [Access.at(0), :name])
-      {"john", [%{}, %{name: "mary"}]}
-
-  When the index is out of bounds, `nil` is returned and the update function is never called:
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.at(10), :name])
-      nil
-      iex> get_and_update_in(list, [Access.at(10), :name], fn
-      ...>   prev -> {prev, String.upcase(prev)}
-      ...> end)
-      {nil, [%{name: "john"}, %{name: "mary"}]}
-
-  An error is raised for negative indexes:
-
-      iex> get_in([], [Access.at(-1)])
-      ** (FunctionClauseError) no function clause matching in Access.at/1
-
-  An error is raised if the accessed structure is not a list:
-
-      iex> get_in(%{}, [Access.at(1)])
-      ** (RuntimeError) Access.at/1 expected a list, got: %{}
-  """
-  def at(index) when index >= 0 do
-    fn(op, data, next) -> at(op, data, index, next) end
-  end
-
-  defp at(:get, data, index, next) when is_list(data) do
-    data |> Enum.at(index) |> next.()
-  end
-
-  defp at(:get_and_update, data, index, next) when is_list(data) do
-    get_and_update_at(data, index, next, [])
-  end
-
-  defp at(_op, data, _index, _next) do
-    raise "Access.at/1 expected a list, got: #{inspect data}"
-  end
-
-  defp get_and_update_at([head | rest], 0, next, updates) do
-    case next.(head) do
-      {get, update} -> {get, :lists.reverse([update | updates], rest)}
-      :pop -> {head, :lists.reverse(updates, rest)}
-    end
-  end
-
-  defp get_and_update_at([head | rest], index, next, updates) do
-    get_and_update_at(rest, index - 1, next, [head | updates])
-  end
-
-  defp get_and_update_at([], _index, _next, updates) do
-    {nil, :lists.reverse(updates)}
+  def access(function, item) do
+    function.(item)
  end
 end
@@ -1,312 +0,0 @@
-defmodule Agent do
-  @moduledoc """
-  Agents are a simple abstraction around state.
-
-  Often in Elixir there is a need to share or store state that
-  must be accessed from different processes or by the same process
-  at different points in time.
-
-  The Agent module provides a basic server implementation that
-  allows state to be retrieved and updated via a simple API.
-
-  ## Examples
-
-  For example, in the Mix tool that ships with Elixir, we need
-  to keep a set of all tasks executed by a given project. Since
-  this set is shared, we can implement it with an Agent:
-
-      defmodule Mix.TasksServer do
-        def start_link do
-          Agent.start_link(fn -> MapSet.new end, name: __MODULE__)
-        end
-
-        @doc "Checks if the task has already executed"
-        def executed?(task, project) do
-          item = {task, project}
-          Agent.get(__MODULE__, fn set ->
-            item in set
-          end)
-        end
-
-        @doc "Marks a task as executed"
-        def put_task(task, project) do
-          item = {task, project}
-          Agent.update(__MODULE__, &MapSet.put(&1, item))
-        end
-
-        @doc "Resets the executed tasks and returns the previous list of tasks"
-        def take_all() do
-          Agent.get_and_update(__MODULE__, fn set ->
-            {Enum.into(set, []), MapSet.new}
-          end)
-        end
-      end
-
-  Note that agents still provide a segregation between the
-  client and server APIs, as seen in GenServers. In particular,
-  all code inside the function passed to the agent is executed
-  by the agent. This distinction is important because you may
-  want to avoid expensive operations inside the agent, as it will
-  effectively block the agent until the request is fulfilled.
-
-  Consider these two examples:
-
-      # Compute in the agent/server
-      def get_something(agent) do
-        Agent.get(agent, fn state -> do_something_expensive(state) end)
-      end
-
-      # Compute in the agent/client
-      def get_something(agent) do
-        Agent.get(agent, &(&1)) |> do_something_expensive()
-      end
-
-  The first function blocks the agent. The second function copies
-  all the state to the client and then executes the operation in the
-  client. The difference is whether the data is large enough to require
-  processing in the server, at least initially, or small enough to be
-  sent to the client cheaply.
-
-  ## Name Registration
-
-  An Agent is bound to the same name registration rules as GenServers.
-  Read more about it in the `GenServer` docs.
-
-  ## A word on distributed agents
-
-  It is important to consider the limitations of distributed agents. Agents
-  provide two APIs, one that works with anonymous functions and another
-  that expects an explicit module, function, and arguments.
-
-  In a distributed setup with multiple nodes, the API that accepts anonymous
-  functions only works if the caller (client) and the agent have the same
-  version of the caller module.
-
-  Keep in mind this issue also shows up when performing "rolling upgrades"
-  with agents. By rolling upgrades we mean the following situation: you wish
-  to deploy a new version of your software by *shutting down* some of your
-  nodes and replacing them with nodes running a new version of the software.
-  In this setup, part of your environment will have one version of a given
-  module and the other part another version (the newer one) of the same module.
-
-  The best solution is to simply use the explicit module, function, and arguments
-  APIs when working with distributed agents.
-
-  ## Hot code swapping
-
-  An agent can have its code hot swapped live by simply passing a module,
-  function, and args tuple to the update instruction. For example, imagine
-  you have an agent named `:sample` and you want to convert its inner state
-  from some dict structure to a map. It can be done with the following
-  instruction:
-
-      {:update, :sample, {:advanced, {Enum, :into, [%{}]}}}
-
-  The agent's state will be added to the given list as the first argument.
-  """
-
-  @typedoc "Return values of `start*` functions"
-  @type on_start :: {:ok, pid} | {:error, {:already_started, pid} | term}
-
-  @typedoc "The agent name"
-  @type name :: atom | {:global, term} | {:via, module, term}
-
-  @typedoc "The agent reference"
-  @type agent :: pid | {atom, node} | name
-
-  @typedoc "The agent state"
-  @type state :: term
-
-  @doc """
-  Starts an agent linked to the current process with the given function.
-
-  This is often used to start the agent as part of a supervision tree.
-
-  Once the agent is spawned, the given function is invoked and its return
-  value is used as the agent state. Note that `start_link` does not return
-  until the given function has returned.
-
-  ## Options
-
-  The `:name` option is used for registration as described in the module
-  documentation.
-
-  If the `:timeout` option is present, the agent is allowed to spend at most
-  the given number of milliseconds on initialization or it will be terminated
-  and the start function will return `{:error, :timeout}`.
-
-  If the `:debug` option is present, the corresponding function in the
-  [`:sys` module](http://www.erlang.org/doc/man/sys.html) will be invoked.
-
-  If the `:spawn_opt` option is present, its value will be passed as options
-  to the underlying process as in `Process.spawn/4`.
-
-  ## Return values
-
-  If the server is successfully created and initialized, the function returns
-  `{:ok, pid}`, where `pid` is the PID of the server. If an agent with the
-  specified name already exists, the function returns
-  `{:error, {:already_started, pid}}` with the PID of that process.
-
-  If the given function callback fails with `reason`, the function returns
-  `{:error, reason}`.
-  """
-  @spec start_link((() -> term), GenServer.options) :: on_start
-  def start_link(fun, options \\ []) when is_function(fun, 0) do
-    GenServer.start_link(Agent.Server, fun, options)
-  end
-
-  @doc """
-  Starts an agent linked to the current process with the given module
-  function and arguments.
-
-  Same as `start_link/2` but a module, function and args are expected
-  instead of an anonymous function.
-  """
-  @spec start_link(module, atom, [any], GenServer.options) :: on_start
-  def start_link(module, fun, args, options \\ []) do
-    GenServer.start_link(Agent.Server, {module, fun, args}, options)
-  end
-
-  @doc """
-  Starts an agent process without links (outside of a supervision tree).
-
-  See `start_link/2` for more information.
-  """
-  @spec start((() -> term), GenServer.options) :: on_start
-  def start(fun, options \\ []) when is_function(fun, 0) do
-    GenServer.start(Agent.Server, fun, options)
-  end
-
-  @doc """
-  Starts an agent with the given module function and arguments.
-
-  Similar to `start/2` but a module, function and args are expected
-  instead of an anonymous function.
-  """
-  @spec start(module, atom, [any], GenServer.options) :: on_start
-  def start(module, fun, args, options \\ []) do
-    GenServer.start(Agent.Server, {module, fun, args}, options)
-  end
-
-  @doc """
-  Gets an agent value via the given function.
-
-  The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The result of the function invocation is
-  returned.
-
-  A timeout can also be specified (it has a default value of 5000).
-  """
-  @spec get(agent, (state -> a), timeout) :: a when a: var
-  def get(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
-    GenServer.call(agent, {:get, fun}, timeout)
-  end
-
-  @doc """
-  Gets an agent value via the given function.
-
-  Same as `get/3` but a module, function and args are expected
-  instead of an anonymous function. The state is added as first
-  argument to the given list of args.
-  """
-  @spec get(agent, module, atom, [term], timeout) :: any
-  def get(agent, module, fun, args, timeout \\ 5000) do
-    GenServer.call(agent, {:get, {module, fun, args}}, timeout)
-  end
-
-  @doc """
-  Gets and updates the agent state in one operation.
-
-  The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The function must return a tuple with two
-  elements, the first being the value to return (i.e. the `get` value)
-  and the second one is the new state.
-
-  A timeout can also be specified (it has a default value of 5000).
-  """
-  @spec get_and_update(agent, (state -> {a, state}), timeout) :: a when a: var
-  def get_and_update(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
-    GenServer.call(agent, {:get_and_update, fun}, timeout)
-  end
-
-  @doc """
-  Gets and updates the agent state in one operation.
-
-  Same as `get_and_update/3` but a module, function and args are expected
-  instead of an anonymous function. The state is added as first
-  argument to the given list of args.
-  """
-  @spec get_and_update(agent, module, atom, [term], timeout) :: any
-  def get_and_update(agent, module, fun, args, timeout \\ 5000) do
-    GenServer.call(agent, {:get_and_update, {module, fun, args}}, timeout)
-  end
-
-  @doc """
-  Updates the agent state.
-
-  The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The function must return the new state.
-
-  A timeout can also be specified (it has a default value of 5000).
-  This function always returns `:ok`.
-  """
-  @spec update(agent, (state -> state), timeout) :: :ok
-  def update(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
-    GenServer.call(agent, {:update, fun}, timeout)
-  end
-
-  @doc """
-  Updates the agent state.
-
-  Same as `update/3` but a module, function and args are expected
-  instead of an anonymous function. The state is added as first
-  argument to the given list of args.
-  """
-  @spec update(agent, module, atom, [term], timeout) :: :ok
-  def update(agent, module, fun, args, timeout \\ 5000) do
-    GenServer.call(agent, {:update, {module, fun, args}}, timeout)
-  end
-
-  @doc """
-  Performs a cast (fire and forget) operation on the agent state.
-
-  The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The function must return the new state.
-
-  Note that `cast` returns `:ok` immediately, regardless of whether the
-  destination node or agent exists.
-  """
-  @spec cast(agent, (state -> state)) :: :ok
-  def cast(agent, fun) when is_function(fun, 1) do
-    GenServer.cast(agent, {:cast, fun})
-  end
-
-  @doc """
-  Performs a cast (fire and forget) operation on the agent state.
-
-  Same as `cast/2` but a module, function and args are expected
-  instead of an anonymous function. The state is added as first
-  argument to the given list of args.
-  """
-  @spec cast(agent, module, atom, [term]) :: :ok
-  def cast(agent, module, fun, args) do
-    GenServer.cast(agent, {:cast, {module, fun, args}})
-  end
-
-  @doc """
-  Stops the agent with the given `reason`.
-
-  It returns `:ok` if the server terminates with the given
-  reason, if it terminates with another reason, the call will
-  exit.
-
-  This function keeps OTP semantics regarding error reporting.
-  If the reason is any other than `:normal`, `:shutdown` or
-  `{:shutdown, _}`, an error report will be logged.
-  """
-  @spec stop(agent, reason :: term, timeout) :: :ok
-  def stop(agent, reason \\ :normal, timeout \\ :infinity) do
-    :gen.stop(agent, reason, timeout)
-  end
-end
@@ -1,59 +0,0 @@
-defmodule Agent.Server do
-  @moduledoc false
-
-  use GenServer
-
-  def init(fun) do
-    _ = initial_call(fun)
-    {:ok, run(fun, [])}
-  end
-
-  def handle_call({:get, fun}, _from, state) do
-    {:reply, run(fun, [state]), state}
-  end
-
-  def handle_call({:get_and_update, fun}, _from, state) do
-    case run(fun, [state]) do
-      {reply, state} -> {:reply, reply, state}
-      other          -> {:stop, {:bad_return_value, other}, state}
-    end
-  end
-
-  def handle_call({:update, fun}, _from, state) do
-    {:reply, :ok, run(fun, [state])}
-  end
-
-  def handle_call(msg, from, state) do
-    super(msg, from, state)
-  end
-
-  def handle_cast({:cast, fun}, state) do
-    {:noreply, run(fun, [state])}
-  end
-
-  def handle_cast(msg, state) do
-    super(msg, state)
-  end
-
-  def code_change(_old, state, fun) do
-    {:ok, run(fun, [state])}
-  end
-
-  defp initial_call(mfa) do
-    _ = Process.put(:"$initial_call", get_initial_call(mfa))
-    :ok
-  end
-
-  defp get_initial_call(fun) when is_function(fun, 0) do
-    {:module, module} = :erlang.fun_info(fun, :module)
-    {:name, name} = :erlang.fun_info(fun, :name)
-    {module, name, 0}
-  end
-
-  defp get_initial_call({mod, fun, args}) do
-    {mod, fun, length(args)}
-  end
-
-  defp run({m, f, a}, extra), do: apply(m, f, extra ++ a)
-  defp run(fun, extra), do: apply(fun, extra)
-end
@@ -1,541 +0,0 @@
-defmodule Application do
-  @moduledoc """
-  A module for working with applications and defining application callbacks.
-
-  In Elixir (actually, in Erlang/OTP), an application is a component
-  implementing some specific functionality, that can be started and stopped
-  as a unit, and which can be re-used in other systems.
-
-  Applications are defined with an application file named `APP.app` where
-  `APP` is the application name, usually in `underscore_case`. The application
-  file must reside in the same `ebin` directory as the compiled modules of the
-  application.
-
-  In Elixir, Mix is responsible for compiling your source code and
-  generating your application `.app` file. Furthermore, Mix is also
-  responsible for configuring, starting and stopping your application
-  and its dependencies. For this reason, this documentation will focus
-  on the remaining aspects of your application: the application environment
-  and the application callback module.
-
-  You can learn more about Mix generation of `.app` files by typing
-  `mix help compile.app`.
-
-  ## Application environment
-
-  Once an application is started, OTP provides an application environment
-  that can be used to configure the application.
-
-  Assuming you are inside a Mix project, you can edit the `application/0`
-  function in the `mix.exs` file to the following:
-
-      def application do
-        [env: [hello: :world]]
-      end
-
-  In the application function, we can define the default environment values
-  for our application. By starting your application with `iex -S mix`, you
-  can access the default value:
-
-      Application.get_env(:APP_NAME, :hello)
-      #=> :world
-
-  It is also possible to put and delete values from the application value,
-  including new values that are not defined in the environment file (although
-  this should be avoided).
-
-  Keep in mind that each application is responsible for its environment.
-  Do not use the functions in this module for directly accessing or modifying
-  the environment of other applications (as it may lead to inconsistent
-  data in the application environment).
-
-  ## Application module callback
-
-  Often times, an application defines a supervision tree that must be started
-  and stopped when the application starts and stops. For such, we need to
-  define an application module callback. The first step is to define the
-  module callback in the application definition in the `mix.exs` file:
-
-      def application do
-        [mod: {MyApp, []}]
-      end
-
-  Our application now requires the `MyApp` module to provide an application
-  callback. This can be done by invoking `use Application` in that module and
-  defining a `start/2` callback, for example:
-
-      defmodule MyApp do
-        use Application
-
-        def start(_type, _args) do
-          MyApp.Supervisor.start_link()
-        end
-      end
-
-  `start/2` typically returns `{:ok, pid}` or `{:ok, pid, state}` where
-  `pid` identifies the supervision tree and `state` is the application state.
-  `args` is the second element of the tuple given to the `:mod` option.
-
-  The `type` argument passed to `start/2` is usually `:normal` unless in a
-  distributed setup where application takeovers and failovers are configured.
-  This particular aspect of applications is explained in more detail in the
-  OTP documentation:
-
-    * [`:application` module](http://www.erlang.org/doc/man/application.html)
-    * [Applications – OTP Design Principles](http://www.erlang.org/doc/design_principles/applications.html)
-
-  A developer may also implement the `stop/1` callback (automatically defined
-  by `use Application`) which does any application cleanup. It receives the
-  application state and can return any value. Note that shutting down the
-  supervisor is automatically handled by the VM.
-  """
-
-  @doc """
-  Called when an application is started.
-
-  This function is called when an the application is started using
-  `Application.start/2` (and functions on top of that, such as
-  `Application.ensure_started/2`). This function should start the top-level
-  process of the application (which should be the top supervisor of the
-  application's supervision tree if the application follows the OTP design
-  principles around supervision).
-
-  `start_type` defines how the application is started:
-
-    * `:normal` - used if the startup is a normal startup or if the application
-      is distributed and is started on the current node because of a failover
-      from another mode and the application specification key `:start_phases`
-      is `:undefined`.
-    * `{:takeover, node}` - used if the application is distributed and is
-      started on the current node because of a failover on the node `node`.
-    * `{:failover, node}` - used if the application is distributed and is
-      started on the current node because of a failover on node `node`, and the
-      application specification key `:start_phases` is not `:undefined`.
-
-  `start_args` are the arguments passed to the application in the `:mod`
-  specification key (e.g., `mod: {MyApp, [:my_args]}`).
-
-  This function should either return `{:ok, pid}` or `{:ok, pid, state}` if
-  startup is successful. `pid` should be the PID of the top supervisor. `state`
-  can be an arbitrary term, and if omitted will default to `[]`; if the
-  application is later stopped, `state` is passed to the `stop/1` callback (see
-  the documentation for the `c:stop/1` callback for more information).
-
-  `use Application` provides no default implementation for the `start/2`
-  callback.
-  """
-  @callback start(start_type, start_args :: term) ::
-    {:ok, pid} |
-    {:ok, pid, state} |
-    {:error, reason :: term}
-
-  @doc """
-  Called when an application is stopped.
-
-  This function is called when an application has stopped, i.e., when its
-  supervision tree has been stopped. It should do the opposite of what the
-  `start/2` callback did, and should perform any necessary cleanup. The return
-  value of this callback is ignored.
-
-  `state` is the return value of the `start/2` callback or the return value of
-  the `prep_stop/1` function if the application module defines such a function.
-
-  `use Application` defines a default implementation of this function which does
-  nothing and just returns `:ok`.
-  """
-  @callback stop(state) :: term
-
-  @doc false
-  defmacro __using__(_) do
-    quote location: :keep do
-      @behaviour Application
-
-      @doc false
-      def stop(_state) do
-        :ok
-      end
-
-      defoverridable [stop: 1]
-    end
-  end
-
-  @type app :: atom
-  @type key :: atom
-  @type value :: term
-  @type state :: term
-  @type start_type :: :permanent | :transient | :temporary
-
-  @application_keys [:description, :id, :vsn, :modules, :maxP, :maxT, :registered,
-                     :included_applications, :applications, :mod, :start_phases]
-
-  @doc """
-  Returns the spec for `app`.
-
-  The following keys are returned:
-
-    * #{Enum.map_join @application_keys, "\n  * ", &inspect/1}
-
-  Note the environment is not returned as it can be accessed via
-  `fetch_env/2`. Returns `nil` if the application is not loaded.
-  """
-  @spec spec(app) :: [{key, value}] | nil
-  def spec(app) do
-    case :application.get_all_key(app) do
-      {:ok, info} -> :lists.keydelete(:env, 1, info)
-      :undefined  -> nil
-    end
-  end
-
-  @doc """
-  Returns the value for `key` in `app`'s specification.
-
-  See `spec/1` for the supported keys. If the given
-  specification parameter does not exist, this function
-  will raise. Returns `nil` if the application is not loaded.
-  """
-  @spec spec(app, key) :: value | nil
-  def spec(app, key) when key in @application_keys do
-    case :application.get_key(app, key) do
-      {:ok, value} -> value
-      :undefined -> nil
-    end
-  end
-
-  @doc """
-  Gets the application for the given module.
-
-  The application is located by analyzing the spec
-  of all loaded applications. Returns `nil` if
-  the module is not listed in any application spec.
-  """
-  @spec get_application(atom) :: atom | nil
-  def get_application(module) when is_atom(module) do
-    case :application.get_application(module) do
-      {:ok, app} -> app
-      :undefined -> nil
-    end
-  end
-
-  @doc """
-  Returns all key-value pairs for `app`.
-  """
-  @spec get_all_env(app) :: [{key, value}]
-  def get_all_env(app) do
-    :application.get_all_env(app)
-  end
-
-  @doc """
-  Returns the value for `key` in `app`'s environment.
-
-  If the configuration parameter does not exist, the function returns the
-  `default` value.
-  """
-  @spec get_env(app, key, value) :: value
-  def get_env(app, key, default \\ nil) do
-    :application.get_env(app, key, default)
-  end
-
-  @doc """
-  Returns the value for `key` in `app`'s environment in a tuple.
-
-  If the configuration parameter does not exist, the function returns `:error`.
-  """
-  @spec fetch_env(app, key) :: {:ok, value} | :error
-  def fetch_env(app, key) do
-    case :application.get_env(app, key) do
-      {:ok, value} -> {:ok, value}
-      :undefined -> :error
-    end
-  end
-
-  @doc """
-  Returns the value for `key` in `app`'s environment.
-
-  If the configuration parameter does not exist, raises `ArgumentError`.
-  """
-  @spec fetch_env!(app, key) :: value | no_return
-  def fetch_env!(app, key) do
-    case fetch_env(app, key) do
-      {:ok, value} -> value
-      :error ->
-        raise ArgumentError,
-          "application #{inspect app} is not loaded, " <>
-          "or the configuration parameter #{inspect key} is not set"
-    end
-  end
-
-  @doc """
-  Puts the `value` in `key` for the given `app`.
-
-  ## Options
-
-    * `:timeout`    - the timeout for the change (defaults to 5000ms)
-    * `:persistent` - persists the given value on application load and reloads
-
-  If `put_env/4` is called before the application is loaded, the application
-  environment values specified in the `.app` file will override the ones
-  previously set.
-
-  The persistent option can be set to `true` when there is a need to guarantee
-  parameters set with this function will not be overridden by the ones defined
-  in the application resource file on load. This means persistent values will
-  stick after the application is loaded and also on application reload.
-  """
-  @spec put_env(app, key, value, [timeout: timeout, persistent: boolean]) :: :ok
-  def put_env(app, key, value, opts \\ []) do
-    :application.set_env(app, key, value, opts)
-  end
-
-  @doc """
-  Deletes the `key` from the given `app` environment.
-
-  See `put_env/4` for a description of the options.
-  """
-  @spec delete_env(app, key, [timeout: timeout, persistent: boolean]) :: :ok
-  def delete_env(app, key, opts \\ []) do
-    :application.unset_env(app, key, opts)
-  end
-
-  @doc """
-  Ensures the given `app` is started.
-
-  Same as `start/2` but returns `:ok` if the application was already
-  started. This is useful in scripts and in test setup, where test
-  applications need to be explicitly started:
-
-      :ok = Application.ensure_started(:my_test_dep)
-
-  """
-  @spec ensure_started(app, start_type) :: :ok | {:error, term}
-  def ensure_started(app, type \\ :temporary) when is_atom(app) do
-    :application.ensure_started(app, type)
-  end
-
-  @doc """
-  Ensures the given `app` and its applications are started.
-
-  Same as `start/2` but also starts the applications listed under
-  `:applications` in the `.app` file in case they were not previously
-  started.
-  """
-  @spec ensure_all_started(app, start_type) :: {:ok, [app]} | {:error, {app, term}}
-  def ensure_all_started(app, type \\ :temporary) when is_atom(app) do
-    :application.ensure_all_started(app, type)
-  end
-
-  @doc """
-  Starts the given `app`.
-
-  If the `app` is not loaded, the application will first be loaded using `load/1`.
-  Any included application, defined in the `:included_applications` key of the
-  `.app` file will also be loaded, but they won't be started.
-
-  Furthermore, all applications listed in the `:applications` key must be explicitly
-  started before this application is. If not, `{:error, {:not_started, app}}` is
-  returned, where `app` is the name of the missing application.
-
-  In case you want to automatically  load **and start** all of `app`'s dependencies,
-  see `ensure_all_started/2`.
-
-  The `type` argument specifies the type of the application:
-
-    * `:permanent` - if `app` terminates, all other applications and the entire
-      node are also terminated.
-
-    * `:transient` - if `app` terminates with `:normal` reason, it is reported
-      but no other applications are terminated. If a transient application
-      terminates abnormally, all other applications and the entire node are
-      also terminated.
-
-    * `:temporary` - if `app` terminates, it is reported but no other
-      applications are terminated (the default).
-
-  Note that it is always possible to stop an application explicitly by calling
-  `stop/1`. Regardless of the type of the application, no other applications will
-  be affected.
-
-  Note also that the `:transient` type is of little practical use, since when a
-  supervision tree terminates, the reason is set to `:shutdown`, not `:normal`.
-  """
-  @spec start(app, start_type) :: :ok | {:error, term}
-  def start(app, type \\ :temporary) when is_atom(app) do
-    :application.start(app, type)
-  end
-
-  @doc """
-  Stops the given `app`.
-
-  When stopped, the application is still loaded.
-  """
-  @spec stop(app) :: :ok | {:error, term}
-  def stop(app) do
-    :application.stop(app)
-  end
-
-  @doc """
-  Loads the given `app`.
-
-  In order to be loaded, an `.app` file must be in the load paths.
-  All `:included_applications` will also be loaded.
-
-  Loading the application does not start it nor load its modules, but
-  it does load its environment.
-  """
-  @spec load(app) :: :ok | {:error, term}
-  def load(app) when is_atom(app) do
-    :application.load(app)
-  end
-
-  @doc """
-  Unloads the given `app`.
-
-  It will also unload all `:included_applications`.
-  Note that the function does not purge the application modules.
-  """
-  @spec unload(app) :: :ok | {:error, term}
-  def unload(app) when is_atom(app) do
-    :application.unload(app)
-  end
-
-  @doc """
-  Gets the directory for app.
-
-  This information is returned based on the code path. Here is an
-  example:
-
-      File.mkdir_p!("foo/ebin")
-      Code.prepend_path("foo/ebin")
-      Application.app_dir(:foo)
-      #=> "foo"
-
-  Even though the directory is empty and there is no `.app` file
-  it is considered the application directory based on the name
-  "foo/ebin". The name may contain a dash `-` which is considered
-  to be the app version and it is removed for the lookup purposes:
-
-      File.mkdir_p!("bar-123/ebin")
-      Code.prepend_path("bar-123/ebin")
-      Application.app_dir(:bar)
-      #=> "bar-123"
-
-  For more information on code paths, check the `Code` module in
-  Elixir and also Erlang's `:code` module.
-  """
-  @spec app_dir(app) :: String.t
-  def app_dir(app) when is_atom(app) do
-    case :code.lib_dir(app) do
-      lib when is_list(lib) -> IO.chardata_to_string(lib)
-      {:error, :bad_name} -> raise ArgumentError, "unknown application: #{inspect app}"
-    end
-  end
-
-  @doc """
-  Returns the given path inside `app_dir/1`.
-  """
-  @spec app_dir(app, String.t | [String.t]) :: String.t
-  def app_dir(app, path) when is_binary(path) do
-    Path.join(app_dir(app), path)
-  end
-  def app_dir(app, path) when is_list(path) do
-    Path.join([app_dir(app) | path])
-  end
-
-  @doc """
-  Returns a list with information about the applications which are currently running.
-  """
-  @spec started_applications(timeout) :: [tuple]
-  def started_applications(timeout \\ 5000) do
-    :application.which_applications(timeout)
-  end
-
-  @doc """
-  Returns a list with information about the applications which have been loaded.
-  """
-  @spec loaded_applications :: [tuple]
-  def loaded_applications do
-    :application.loaded_applications
-  end
-
-  @doc """
-  Formats the error reason returned by `start/2`,
-  `ensure_started/2`, `stop/1`, `load/1` and `unload/1`,
-  returns a string.
-  """
-  @spec format_error(any) :: String.t
-  def format_error(reason) do
-    try do
-      do_format_error(reason)
-    catch
-      # A user could create an error that looks like a built-in one
-      # causing an error.
-      :error, _ ->
-        inspect(reason)
-    end
-  end
-
-  # exit(:normal) call is special cased, undo the special case.
-  defp do_format_error({{:EXIT, :normal}, {mod, :start, args}}) do
-    Exception.format_exit({:normal, {mod, :start, args}})
-  end
-
-  # {:error, reason} return value
-  defp do_format_error({reason, {mod, :start, args}}) do
-    Exception.format_mfa(mod, :start, args) <> " returned an error: " <>
-      Exception.format_exit(reason)
-  end
-
-  # error or exit(reason) call, use exit reason as reason.
-  defp do_format_error({:bad_return, {{mod, :start, args}, {:EXIT, reason}}}) do
-    Exception.format_exit({reason, {mod, :start, args}})
-  end
-
-  # bad return value
-  defp do_format_error({:bad_return, {{mod, :start, args}, return}}) do
-    Exception.format_mfa(mod, :start, args) <>
-      " returned a bad value: " <> inspect(return)
-  end
-
-  defp do_format_error({:already_started, app}) when is_atom(app) do
-    "already started application #{app}"
-  end
-
-  defp do_format_error({:not_started, app}) when is_atom(app) do
-    "not started application #{app}"
-  end
-
-  defp do_format_error({:bad_application, app}) do
-    "bad application: #{inspect(app)}"
-  end
-
-  defp do_format_error({:already_loaded, app}) when is_atom(app) do
-    "already loaded application #{app}"
-  end
-
-  defp do_format_error({:not_loaded, app}) when is_atom(app) do
-    "not loaded application #{app}"
-  end
-
-  defp do_format_error({:invalid_restart_type, restart}) do
-    "invalid application restart type: #{inspect(restart)}"
-  end
-
-  defp do_format_error({:invalid_name, name}) do
-    "invalid application name: #{inspect(name)}"
-  end
-
-  defp do_format_error({:invalid_options, opts}) do
-    "invalid application options: #{inspect(opts)}"
-  end
-
-  defp do_format_error({:badstartspec, spec}) do
-    "bad application start specs: #{inspect(spec)}"
-  end
-
-  defp do_format_error({'no such file or directory', file}) do
-    "could not find application file: #{file}"
-  end
-
-  defp do_format_error(reason) do
-    Exception.format_exit(reason)
-  end
-end
@@ -1,44 +0,0 @@
-defmodule Atom do
-  @moduledoc """
-  Convenience functions for working with atoms.
-
-  See also `Kernel.is_atom/1`.
-  """
-
-  @doc """
-  Converts an atom to a string.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Atom.to_string(:foo)
-      "foo"
-
-  """
-  @spec to_string(atom) :: String.t
-  def to_string(atom) do
-    :erlang.atom_to_binary(atom, :utf8)
-  end
-
-  @doc """
-  Converts an atom to a charlist.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Atom.to_charlist(:"An atom")
-      'An atom'
-
-  """
-  @spec to_charlist(atom) :: charlist
-  def to_charlist(atom) do
-    :erlang.atom_to_list(atom)
-  end
-
-  # TODO: Deprecate by v1.5
-  @doc false
-  @spec to_char_list(atom) :: charlist
-  def to_char_list(atom), do: Atom.to_charlist(atom)
-end
@@ -1,944 +0,0 @@
-defmodule Base do
-  import Bitwise
-
-  @moduledoc """
-  This module provides data encoding and decoding functions
-  according to [RFC 4648](http://tools.ietf.org/html/rfc4648).
-
-  This document defines the commonly used base 16, base 32, and base
-  64 encoding schemes.
-
-  ## Base 16 alphabet
-
-      | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
-      |------:|---------:|------:|---------:|------:|---------:|------:|---------:|
-      |      0|         0|      4|         4|      8|         8|     12|         C|
-      |      1|         1|      5|         5|      9|         9|     13|         D|
-      |      2|         2|      6|         6|     10|         A|     14|         E|
-      |      3|         3|      7|         7|     11|         B|     15|         F|
-
-  ## Base 32 alphabet
-
-      | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
-      |------:|---------:|------:|---------:|------:|---------:|------:|---------:|
-      |      0|         A|      9|         J|     18|         S|     27|         3|
-      |      1|         B|     10|         K|     19|         T|     28|         4|
-      |      2|         C|     11|         L|     20|         U|     29|         5|
-      |      3|         D|     12|         M|     21|         V|     30|         6|
-      |      4|         E|     13|         N|     22|         W|     31|         7|
-      |      5|         F|     14|         O|     23|         X|       |          |
-      |      6|         G|     15|         P|     24|         Y|  (pad)|         =|
-      |      7|         H|     16|         Q|     25|         Z|       |          |
-      |      8|         I|     17|         R|     26|         2|       |          |
-
-
-  ## Base 32 (extended hex) alphabet
-
-      | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
-      |------:|---------:|------:|---------:|------:|---------:|------:|---------:|
-      |      0|         0|      9|         9|     18|         I|     27|         R|
-      |      1|         1|     10|         A|     19|         J|     28|         S|
-      |      2|         2|     11|         B|     20|         K|     29|         T|
-      |      3|         3|     12|         C|     21|         L|     30|         U|
-      |      4|         4|     13|         D|     22|         M|     31|         V|
-      |      5|         5|     14|         E|     23|         N|       |          |
-      |      6|         6|     15|         F|     24|         O|  (pad)|         =|
-      |      7|         7|     16|         G|     25|         P|       |          |
-      |      8|         8|     17|         H|     26|         Q|       |          |
-
-  ## Base 64 alphabet
-
-      | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
-      |------:|---------:|------:|---------:|------:|---------:|------:|---------:|
-      |      0|         A|     17|         R|     34|         i|     51|         z|
-      |      1|         B|     18|         S|     35|         j|     52|         0|
-      |      2|         C|     19|         T|     36|         k|     53|         1|
-      |      3|         D|     20|         U|     37|         l|     54|         2|
-      |      4|         E|     21|         V|     38|         m|     55|         3|
-      |      5|         F|     22|         W|     39|         n|     56|         4|
-      |      6|         G|     23|         X|     40|         o|     57|         5|
-      |      7|         H|     24|         Y|     41|         p|     58|         6|
-      |      8|         I|     25|         Z|     42|         q|     59|         7|
-      |      9|         J|     26|         a|     43|         r|     60|         8|
-      |     10|         K|     27|         b|     44|         s|     61|         9|
-      |     11|         L|     28|         c|     45|         t|     62|         +|
-      |     12|         M|     29|         d|     46|         u|     63|         /|
-      |     13|         N|     30|         e|     47|         v|       |          |
-      |     14|         O|     31|         f|     48|         w|  (pad)|         =|
-      |     15|         P|     32|         g|     49|         x|       |          |
-      |     16|         Q|     33|         h|     50|         y|       |          |
-
-  ## Base 64 (URL and filename safe) alphabet
-
-      | Value | Encoding | Value | Encoding | Value | Encoding | Value | Encoding |
-      |------:|---------:|------:|---------:|------:|---------:|------:|---------:|
-      |      0|         A|     17|         R|     34|         i|     51|         z|
-      |      1|         B|     18|         S|     35|         j|     52|         0|
-      |      2|         C|     19|         T|     36|         k|     53|         1|
-      |      3|         D|     20|         U|     37|         l|     54|         2|
-      |      4|         E|     21|         V|     38|         m|     55|         3|
-      |      5|         F|     22|         W|     39|         n|     56|         4|
-      |      6|         G|     23|         X|     40|         o|     57|         5|
-      |      7|         H|     24|         Y|     41|         p|     58|         6|
-      |      8|         I|     25|         Z|     42|         q|     59|         7|
-      |      9|         J|     26|         a|     43|         r|     60|         8|
-      |     10|         K|     27|         b|     44|         s|     61|         9|
-      |     11|         L|     28|         c|     45|         t|     62|         -|
-      |     12|         M|     29|         d|     46|         u|     63|         _|
-      |     13|         N|     30|         e|     47|         v|       |          |
-      |     14|         O|     31|         f|     48|         w|  (pad)|         =|
-      |     15|         P|     32|         g|     49|         x|       |          |
-      |     16|         Q|     33|         h|     50|         y|       |          |
-
-  """
-
-  b16_alphabet    = Enum.with_index '0123456789ABCDEF'
-  b64_alphabet    = Enum.with_index 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
-  b64url_alphabet = Enum.with_index 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_'
-  b32_alphabet    = Enum.with_index 'ABCDEFGHIJKLMNOPQRSTUVWXYZ234567'
-  b32hex_alphabet = Enum.with_index '0123456789ABCDEFGHIJKLMNOPQRSTUV'
-
-  Enum.each [{:enc16,    :dec16,    b16_alphabet},
-             {:enc32,    :dec32,    b32_alphabet},
-             {:enc64,    :dec64,    b64_alphabet},
-             {:enc64url, :dec64url, b64url_alphabet},
-             {:enc32hex, :dec32hex, b32hex_alphabet}], fn({enc, dec, alphabet}) ->
-    for {encoding, value} <- alphabet do
-      defp unquote(enc)(unquote(value)), do: unquote(encoding)
-      defp unquote(dec)(unquote(encoding)), do: unquote(value)
-    end
-    defp unquote(dec)(c) do
-      raise ArgumentError, "non-alphabet digit found: #{inspect <<c>>, binaries: :as_strings} (byte #{c})"
-    end
-  end
-
-  @compile {:inline, from_upper: 1, from_lower: 1, from_mixed: 1,
-                     to_lower: 1, to_upper: 1, enc16: 1, dec16: 1,
-                     enc32: 1, dec32: 1, enc32hex: 1, dec32hex: 1,
-                     enc64: 1, dec64: 1, enc64url: 1, dec64url: 1}
-
-  defp to_lower(char) when char in ?A..?Z,
-    do: char + (?a - ?A)
-  defp to_lower(char),
-    do: char
-
-  defp to_upper(char), do: char
-
-  defp from_upper(char), do: char
-
-  defp from_lower(char) when char in ?a..?z,
-    do: char - (?a - ?A)
-  defp from_lower(char) when not char in ?A..?Z,
-    do: char
-  defp from_lower(char),
-    do: raise(ArgumentError, "non-alphabet digit found: \"#{<<char>>}\" (byte #{char})")
-
-  defp from_mixed(char) when char in ?a..?z,
-    do: char - (?a - ?A)
-  defp from_mixed(char),
-    do: char
-
-  defp maybe_pad(subject, false, _, _),
-    do: subject
-  defp maybe_pad(subject, _, group_size, pad) do
-    case rem(byte_size(subject), group_size) do
-      0 -> subject
-      x -> subject <> String.duplicate(pad, group_size - x)
-    end
-  end
-
-  @doc """
-  Encodes a binary string into a base 16 encoded string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to use when encoding
-
-  The values for `:case` can be:
-
-    * `:upper` - uses upper case characters (default)
-    * `:lower` - uses lower case characters
-
-  ## Examples
-
-      iex> Base.encode16("foobar")
-      "666F6F626172"
-
-      iex> Base.encode16("foobar", case: :lower)
-      "666f6f626172"
-
-  """
-  @spec encode16(binary) :: binary
-  @spec encode16(binary, Keyword.t) :: binary
-  def encode16(data, opts \\ []) when is_binary(data) do
-    case = Keyword.get(opts, :case, :upper)
-    do_encode16(case, data)
-  end
-
-  @doc """
-  Decodes a base 16 encoded string into a binary string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  ## Examples
-
-      iex> Base.decode16("666F6F626172")
-      {:ok, "foobar"}
-
-      iex> Base.decode16("666f6f626172", case: :lower)
-      {:ok, "foobar"}
-
-      iex> Base.decode16("666f6F626172", case: :mixed)
-      {:ok, "foobar"}
-
-  """
-  @spec decode16(binary) :: {:ok, binary} | :error
-  @spec decode16(binary, Keyword.t) :: {:ok, binary} | :error
-  def decode16(string, opts \\ []) do
-    {:ok, decode16!(string, opts)}
-  rescue
-    ArgumentError -> :error
-  end
-
-  @doc """
-  Decodes a base 16 encoded string into a binary string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  An `ArgumentError` exception is raised if the padding is incorrect or
-  a non-alphabet character is present in the string.
-
-  ## Examples
-
-      iex> Base.decode16!("666F6F626172")
-      "foobar"
-
-      iex> Base.decode16!("666f6f626172", case: :lower)
-      "foobar"
-
-      iex> Base.decode16!("666f6F626172", case: :mixed)
-      "foobar"
-
-  """
-  @spec decode16!(binary) :: binary
-  @spec decode16!(binary, Keyword.t) :: binary
-  def decode16!(string, opts \\ [])
-
-  def decode16!(string, opts) when is_binary(string) and rem(byte_size(string), 2) == 0 do
-    case = Keyword.get(opts, :case, :upper)
-    do_decode16(case, string)
-  end
-
-  def decode16!(string, _opts) when is_binary(string) do
-    raise ArgumentError, "odd-length string"
-  end
-
-  @doc """
-  Encodes a binary string into a base 64 encoded string.
-
-  Accepts `padding: false` option which will omit padding from
-  the output string.
-
-  ## Examples
-
-      iex> Base.encode64("foobar")
-      "Zm9vYmFy"
-
-      iex> Base.encode64("foob")
-      "Zm9vYg=="
-
-      iex> Base.encode64("foob", padding: false)
-      "Zm9vYg"
-
-  """
-  @spec encode64(binary) :: binary
-  @spec encode64(binary, Keyword.t) :: binary
-  def encode64(data, opts \\ []) when is_binary(data) do
-    pad? = Keyword.get(opts, :padding, true)
-    do_encode64(data, pad?)
-  end
-
-  @doc """
-  Decodes a base 64 encoded string into a binary string.
-
-  Accepts `ignore: :whitespace` option which will ignore all the
-  whitespace characters in the input string.
-
-  Accepts `padding: false` option which will ignore padding from
-  the input string.
-
-  ## Examples
-
-      iex> Base.decode64("Zm9vYmFy")
-      {:ok, "foobar"}
-
-      iex> Base.decode64("Zm9vYmFy\\n", ignore: :whitespace)
-      {:ok, "foobar"}
-
-      iex> Base.decode64("Zm9vYg==")
-      {:ok, "foob"}
-
-      iex> Base.decode64("Zm9vYg", padding: false)
-      {:ok, "foob"}
-
-  """
-  @spec decode64(binary) :: {:ok, binary} | :error
-  @spec decode64(binary, Keyword.t) :: {:ok, binary} | :error
-  def decode64(string, opts \\ []) when is_binary(string) do
-    {:ok, decode64!(string, opts)}
-  rescue
-    ArgumentError -> :error
-  end
-
-  @doc """
-  Decodes a base 64 encoded string into a binary string.
-
-  Accepts `ignore: :whitespace` option which will ignore all the
-  whitespace characters in the input string.
-
-  Accepts `padding: false` option which will ignore padding from
-  the input string.
-
-  An `ArgumentError` exception is raised if the padding is incorrect or
-  a non-alphabet character is present in the string.
-
-  ## Examples
-
-      iex> Base.decode64!("Zm9vYmFy")
-      "foobar"
-
-      iex> Base.decode64!("Zm9vYmFy\\n", ignore: :whitespace)
-      "foobar"
-
-      iex> Base.decode64!("Zm9vYg==")
-      "foob"
-
-      iex> Base.decode64!("Zm9vYg", padding: false)
-      "foob"
-
-  """
-  @spec decode64!(binary) :: binary
-  @spec decode64!(binary, Keyword.t) :: binary
-  def decode64!(string, opts \\ []) when is_binary(string) do
-    pad? = Keyword.get(opts, :padding, true)
-    string |> remove_ignored(opts[:ignore]) |> do_decode64(pad?)
-  end
-
-  @doc """
-  Encodes a binary string into a base 64 encoded string with URL and filename
-  safe alphabet.
-
-  Accepts `padding: false` option which will omit padding from
-  the output string.
-
-  ## Examples
-
-      iex> Base.url_encode64(<<255, 127, 254, 252>>)
-      "_3_-_A=="
-
-      iex> Base.url_encode64(<<255, 127, 254, 252>>, padding: false)
-      "_3_-_A"
-
-  """
-  @spec url_encode64(binary) :: binary
-  @spec url_encode64(binary, Keyword.t) :: binary
-  def url_encode64(data, opts \\ []) when is_binary(data) do
-    pad? = Keyword.get(opts, :padding, true)
-    do_encode64url(data, pad?)
-  end
-
-  @doc """
-  Decodes a base 64 encoded string with URL and filename safe alphabet
-  into a binary string.
-
-  Accepts `ignore: :whitespace` option which will ignore all the
-  whitespace characters in the input string.
-
-  Accepts `padding: false` option which will ignore padding from
-  the input string.
-
-  ## Examples
-
-      iex> Base.url_decode64("_3_-_A==")
-      {:ok, <<255, 127, 254, 252>>}
-
-      iex> Base.url_decode64("_3_-_A==\\n", ignore: :whitespace)
-      {:ok, <<255, 127, 254, 252>>}
-
-      iex> Base.url_decode64("_3_-_A", padding: false)
-      {:ok, <<255, 127, 254, 252>>}
-
-  """
-  @spec url_decode64(binary) :: {:ok, binary} | :error
-  @spec url_decode64(binary, Keyword.t) :: {:ok, binary} | :error
-  def url_decode64(string, opts \\ []) when is_binary(string) do
-    {:ok, url_decode64!(string, opts)}
-  rescue
-    ArgumentError -> :error
-  end
-
-  @doc """
-  Decodes a base 64 encoded string with URL and filename safe alphabet
-  into a binary string.
-
-  Accepts `ignore: :whitespace` option which will ignore all the
-  whitespace characters in the input string.
-
-  Accepts `padding: false` option which will ignore padding from
-  the input string.
-
-  An `ArgumentError` exception is raised if the padding is incorrect or
-  a non-alphabet character is present in the string.
-
-  ## Examples
-
-      iex> Base.url_decode64!("_3_-_A==")
-      <<255, 127, 254, 252>>
-
-      iex> Base.url_decode64!("_3_-_A==\\n", ignore: :whitespace)
-      <<255, 127, 254, 252>>
-
-      iex> Base.url_decode64!("_3_-_A", padding: false)
-      <<255, 127, 254, 252>>
-
-  """
-  @spec url_decode64!(binary) :: binary
-  @spec url_decode64!(binary, Keyword.t) :: binary
-  def url_decode64!(string, opts \\ []) when is_binary(string)  do
-    pad? = Keyword.get(opts, :padding, true)
-    string |> remove_ignored(opts[:ignore]) |> do_decode64url(pad?)
-  end
-
-  @doc """
-  Encodes a binary string into a base 32 encoded string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to use when encoding
-    * `:padding` - specifies whether to apply padding
-
-  The values for `:case` can be:
-
-    * `:upper` - uses upper case characters (default)
-    * `:lower` - uses lower case characters
-
-  The values for `:padding` can be:
-
-    * `true` - pad the output string to the nearest multiple of 8 (default)
-    * `false` - omit padding from the output string
-
-  ## Examples
-
-      iex> Base.encode32("foobar")
-      "MZXW6YTBOI======"
-
-      iex> Base.encode32("foobar", case: :lower)
-      "mzxw6ytboi======"
-
-      iex> Base.encode32("foobar", padding: false)
-      "MZXW6YTBOI"
-
-  """
-  @spec encode32(binary) :: binary
-  @spec encode32(binary, Keyword.t) :: binary
-  def encode32(data, opts \\ []) when is_binary(data) do
-    case = Keyword.get(opts, :case, :upper)
-    pad? = Keyword.get(opts, :padding, true)
-    do_encode32(case, data, pad?)
-  end
-
-  @doc """
-  Decodes a base 32 encoded string into a binary string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-    * `:padding` - specifies whether to require padding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows  upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  The values for `:padding` can be:
-
-    * `true` - requires the input string to be padded to the nearest multiple of 8 (default)
-    * `false` - ignores padding from the input string
-
-  ## Examples
-
-      iex> Base.decode32("MZXW6YTBOI======")
-      {:ok, "foobar"}
-
-      iex> Base.decode32("mzxw6ytboi======", case: :lower)
-      {:ok, "foobar"}
-
-      iex> Base.decode32("mzXW6ytBOi======", case: :mixed)
-      {:ok, "foobar"}
-
-      iex> Base.decode32("MZXW6YTBOI", padding: false)
-      {:ok, "foobar"}
-
-  """
-  @spec decode32(binary) :: {:ok, binary} | :error
-  @spec decode32(binary, Keyword.t) :: {:ok, binary} | :error
-  def decode32(string, opts \\ []) do
-    {:ok, decode32!(string, opts)}
-  rescue
-    ArgumentError -> :error
-  end
-
-  @doc """
-  Decodes a base 32 encoded string into a binary string.
-
-  An `ArgumentError` exception is raised if the padding is incorrect or
-  a non-alphabet character is present in the string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-    * `:padding` - specifies whether to require padding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  The values for `:padding` can be:
-
-    * `true` - requires the input string to be padded to the nearest multiple of 8 (default)
-    * `false` - ignores padding from the input string
-
-  ## Examples
-
-      iex> Base.decode32!("MZXW6YTBOI======")
-      "foobar"
-
-      iex> Base.decode32!("mzxw6ytboi======", case: :lower)
-      "foobar"
-
-      iex> Base.decode32!("mzXW6ytBOi======", case: :mixed)
-      "foobar"
-
-      iex> Base.decode32!("MZXW6YTBOI", padding: false)
-      "foobar"
-
-  """
-  @spec decode32!(binary) :: binary
-  @spec decode32!(binary, Keyword.t) :: binary
-  def decode32!(string, opts \\ []) when is_binary(string) do
-    case = Keyword.get(opts, :case, :upper)
-    pad? = Keyword.get(opts, :padding, true)
-    do_decode32(case, string, pad?)
-  end
-
-  @doc """
-  Encodes a binary string into a base 32 encoded string with an
-  extended hexadecimal alphabet.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to use when encoding
-    * `:padding` - specifies whether to apply padding
-
-  The values for `:case` can be:
-
-    * `:upper` - uses upper case characters (default)
-    * `:lower` - uses lower case characters
-
-  The values for `:padding` can be:
-
-    * `true` - pad the output string to the nearest multiple of 8 (default)
-    * `false` - omit padding from the output string
-
-  ## Examples
-
-      iex> Base.hex_encode32("foobar")
-      "CPNMUOJ1E8======"
-
-      iex> Base.hex_encode32("foobar", case: :lower)
-      "cpnmuoj1e8======"
-
-      iex> Base.hex_encode32("foobar", padding: false)
-      "CPNMUOJ1E8"
-
-  """
-  @spec hex_encode32(binary) :: binary
-  @spec hex_encode32(binary, Keyword.t) :: binary
-  def hex_encode32(data, opts \\ []) when is_binary(data) do
-    case = Keyword.get(opts, :case, :upper)
-    pad? = Keyword.get(opts, :padding, true)
-    do_hex_encode32(case, data, pad?)
-  end
-
-  @doc """
-  Decodes a base 32 encoded string with extended hexadecimal alphabet
-  into a binary string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-    * `:padding` - specifies whether to require padding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  The values for `:padding` can be:
-
-    * `true` - requires the input string to be padded to the nearest multiple of 8 (default)
-    * `false` - ignores padding from the input string
-
-  ## Examples
-
-      iex> Base.hex_decode32("CPNMUOJ1E8======")
-      {:ok, "foobar"}
-
-      iex> Base.hex_decode32("cpnmuoj1e8======", case: :lower)
-      {:ok, "foobar"}
-
-      iex> Base.hex_decode32("cpnMuOJ1E8======", case: :mixed)
-      {:ok, "foobar"}
-
-      iex> Base.hex_decode32("CPNMUOJ1E8", padding: false)
-      {:ok, "foobar"}
-
-  """
-  @spec hex_decode32(binary) :: {:ok, binary} | :error
-  @spec hex_decode32(binary, Keyword.t) :: {:ok, binary} | :error
-  def hex_decode32(string, opts \\ []) do
-    {:ok, hex_decode32!(string, opts)}
-  rescue
-    ArgumentError -> :error
-  end
-
-  @doc """
-  Decodes a base 32 encoded string with extended hexadecimal alphabet
-  into a binary string.
-
-  An `ArgumentError` exception is raised if the padding is incorrect or
-  a non-alphabet character is present in the string.
-
-  ## Options
-
-  The accepted options are:
-
-    * `:case` - specifies the character case to accept when decoding
-    * `:padding` - specifies whether to require padding
-
-  The values for `:case` can be:
-
-    * `:upper` - only allows upper case characters (default)
-    * `:lower` - only allows lower case characters
-    * `:mixed` - allows mixed case characters
-
-  The values for `:padding` can be:
-
-    * `true` - requires the input string to be padded to the nearest multiple of 8 (default)
-    * `false` - ignores padding from the input string
-
-  ## Examples
-
-      iex> Base.hex_decode32!("CPNMUOJ1E8======")
-      "foobar"
-
-      iex> Base.hex_decode32!("cpnmuoj1e8======", case: :lower)
-      "foobar"
-
-      iex> Base.hex_decode32!("cpnMuOJ1E8======", case: :mixed)
-      "foobar"
-
-      iex> Base.hex_decode32!("CPNMUOJ1E8", padding: false)
-      "foobar"
-
-  """
-  @spec hex_decode32!(binary) :: binary
-  @spec hex_decode32!(binary, Keyword.t) :: binary
-  def hex_decode32!(string, opts \\ []) when is_binary(string) do
-    case = Keyword.get(opts, :case, :upper)
-    pad? = Keyword.get(opts, :padding, true)
-    do_hex_decode32(case, string, pad?)
-  end
-
-  defp remove_ignored(string, nil), do: string
-  defp remove_ignored(string, :whitespace) do
-    for <<c::8 <- string>>, not c in '\s\t\r\n', into: <<>>, do: <<c::8>>
-  end
-
-  defp do_encode16(_, <<>>), do: <<>>
-  defp do_encode16(:upper, data) do
-    for <<c::4 <- data>>, into: <<>>, do: <<enc16(c)::8>>
-  end
-  defp do_encode16(:lower, data) do
-    for <<c::4 <- data>>, into: <<>>, do: <<to_lower(enc16(c))::8>>
-  end
-
-  defp do_decode16(_, <<>>), do: <<>>
-  defp do_decode16(:upper, string) when rem(byte_size(string), 2) == 0 do
-    for <<c1::8, c2::8 <- string>>, into: <<>> do
-      <<dec16(c1)::4, dec16(c2)::4>>
-    end
-  end
-  defp do_decode16(:lower, string) when rem(byte_size(string), 2) == 0 do
-    for <<c1::8, c2::8 <- string>>, into: <<>> do
-      <<dec16(from_lower(c1))::4, dec16(from_lower(c2))::4>>
-    end
-  end
-  defp do_decode16(:mixed, string) when rem(byte_size(string), 2) == 0 do
-    for <<c1::8, c2::8 <- string>>, into: <<>> do
-      <<dec16(from_mixed(c1))::4, dec16(from_mixed(c2))::4>>
-    end
-  end
-
-  defp do_encode64(<<>>, _), do: <<>>
-  defp do_encode64(data, pad?) do
-    split =  3 * div(byte_size(data), 3)
-    <<main::size(split)-binary, rest::binary>> = data
-    main = for <<c::6 <- main>>, into: <<>>, do: <<enc64(c)::8>>
-    tail = case rest do
-      <<c1::6, c2::6, c3::4>> ->
-        <<enc64(c1)::8, enc64(c2)::8, enc64(bsl(c3, 2))::8>>
-      <<c1::6, c2::2>> ->
-        <<enc64(c1)::8, enc64(bsl(c2, 4))::8>>
-      <<>> ->
-        <<>>
-    end
-    main <> maybe_pad(tail, pad?, 4, "=")
-  end
-
-  defp do_decode64(<<>>, _), do: <<>>
-  defp do_decode64(string, false) do
-    maybe_pad(string, true, 4, "=") |> do_decode64(true)
-  end
-  defp do_decode64(string, _pad?) when rem(byte_size(string), 4) == 0 do
-    split = byte_size(string) - 4
-    <<main::size(split)-binary, rest::binary>> = string
-    main = for <<c::8 <- main>>, into: <<>>, do: <<dec64(c)::6>>
-    tail = case rest do
-      <<c1::8, c2::8, ?=, ?=>> ->
-        <<dec64(c1)::6, bsr(dec64(c2), 4)::2>>
-      <<c1::8, c2::8, c3::8, ?=>> ->
-        <<dec64(c1)::6, dec64(c2)::6, bsr(dec64(c3), 2)::4>>
-      <<c1::8, c2::8, c3::8, c4::8>> ->
-        <<dec64(c1)::6, dec64(c2)::6, dec64(c3)::6, dec64(c4)::6>>
-      <<>> ->
-        <<>>
-    end
-    main <> tail
-  end
-  defp do_decode64(_, _) do
-    raise ArgumentError, "incorrect padding"
-  end
-
-  defp do_encode64url(<<>>, _), do: <<>>
-  defp do_encode64url(data, pad?) do
-    split =  3 * div(byte_size(data), 3)
-    <<main::size(split)-binary, rest::binary>> = data
-    main = for <<c::6 <- main>>, into: <<>>, do: <<enc64url(c)::8>>
-    tail = case rest do
-      <<c1::6, c2::6, c3::4>> ->
-        <<enc64url(c1)::8, enc64url(c2)::8, enc64url(bsl(c3, 2))::8>>
-      <<c1::6, c2::2>> ->
-        <<enc64url(c1)::8, enc64url(bsl(c2, 4))::8>>
-      <<>> ->
-        <<>>
-    end
-    main <> maybe_pad(tail, pad?, 4, "=")
-  end
-
-  defp do_decode64url(<<>>, _), do: <<>>
-  defp do_decode64url(string, false) do
-    maybe_pad(string, true, 4, "=") |> do_decode64url(true)
-  end
-  defp do_decode64url(string, _pad?) when rem(byte_size(string), 4) == 0 do
-    split = byte_size(string) - 4
-    <<main::size(split)-binary, rest::binary>> = string
-    main = for <<c::8 <- main>>, into: <<>>, do: <<dec64url(c)::6>>
-    tail = case rest do
-      <<c1::8, c2::8, ?=, ?=>> ->
-        <<dec64url(c1)::6, bsr(dec64url(c2), 4)::2>>
-      <<c1::8, c2::8, c3::8, ?=>> ->
-        <<dec64url(c1)::6, dec64url(c2)::6, bsr(dec64url(c3), 2)::4>>
-      <<c1::8, c2::8, c3::8, c4::8>> ->
-        <<dec64url(c1)::6, dec64url(c2)::6, dec64url(c3)::6, dec64url(c4)::6>>
-      <<>> ->
-        <<>>
-    end
-    main <> tail
-  end
-  defp do_decode64url(_, _) do
-    raise ArgumentError, "incorrect padding"
-  end
-
-  defp do_encode32(_, <<>>, _), do: <<>>
-
-  for {case, fun} <- [upper: :to_upper, lower: :to_lower] do
-    defp do_encode32(unquote(case), data, pad?) do
-      split =  5 * div(byte_size(data), 5)
-      <<main::size(split)-binary, rest::binary>> = data
-      main = for <<c::5 <- main>>, into: <<>>, do: <<unquote(fun)(enc32(c))::8>>
-      tail = case rest do
-        <<c1::5, c2::5, c3::5, c4::5, c5::5, c6::5, c7::2>> ->
-          <<unquote(fun)(enc32(c1))::8, unquote(fun)(enc32(c2))::8,
-            unquote(fun)(enc32(c3))::8, unquote(fun)(enc32(c4))::8,
-            unquote(fun)(enc32(c5))::8, unquote(fun)(enc32(c6))::8,
-            unquote(fun)(enc32(bsl(c7, 3)))::8>>
-        <<c1::5, c2::5, c3::5, c4::5, c5::4>> ->
-          <<unquote(fun)(enc32(c1))::8, unquote(fun)(enc32(c2))::8,
-            unquote(fun)(enc32(c3))::8, unquote(fun)(enc32(c4))::8,
-            unquote(fun)(enc32(bsl(c5, 1)))::8>>
-        <<c1::5, c2::5, c3::5, c4::1>> ->
-          <<unquote(fun)(enc32(c1))::8, unquote(fun)(enc32(c2))::8,
-            unquote(fun)(enc32(c3))::8, unquote(fun)(enc32(bsl(c4, 4)))::8>>
-        <<c1::5, c2::3>> ->
-          <<unquote(fun)(enc32(c1))::8, unquote(fun)(enc32(bsl(c2, 2)))::8>>
-        <<>> ->
-          <<>>
-      end
-      main <> maybe_pad(tail, pad?, 8, "=")
-    end
-  end
-
-  defp do_decode32(_, <<>>, _), do: <<>>
-  defp do_decode32(case, string, false),
-    do: do_decode32(case, maybe_pad(string, true, 8, "="), true)
-
-  for {case, fun} <- [upper: :from_upper, lower: :from_lower, mixed: :from_mixed] do
-    defp do_decode32(unquote(case), string, _pad?) when rem(byte_size(string), 8) == 0 do
-      split = byte_size(string) - 8
-      <<main::size(split)-binary, rest::binary>> = string
-      main = for <<c::8 <- main>>, into: <<>>, do: <<dec32(unquote(fun)(c))::5>>
-      tail = case rest do
-        <<c1::8, c2::8, ?=, ?=, ?=, ?=, ?=, ?=>> ->
-          <<dec32(unquote(fun)(c1))::5, bsr(dec32(unquote(fun)(c2)), 2)::3>>
-        <<c1::8, c2::8, c3::8, c4::8, ?=, ?=, ?=, ?=>> ->
-          <<dec32(unquote(fun)(c1))::5, dec32(unquote(fun)(c2))::5,
-            dec32(unquote(fun)(c3))::5, bsr(dec32(unquote(fun)(c4)), 4)::1>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, ?=, ?=, ?=>> ->
-          <<dec32(unquote(fun)(c1))::5, dec32(unquote(fun)(c2))::5,
-            dec32(unquote(fun)(c3))::5, dec32(unquote(fun)(c4))::5,
-            bsr(dec32(unquote(fun)(c5)), 1)::4>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, ?=>> ->
-          <<dec32(unquote(fun)(c1))::5, dec32(unquote(fun)(c2))::5,
-            dec32(unquote(fun)(c3))::5, dec32(unquote(fun)(c4))::5,
-            dec32(unquote(fun)(c5))::5, dec32(unquote(fun)(c6))::5,
-            bsr(dec32(unquote(fun)(c7)), 3)::2>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8>> ->
-          <<dec32(unquote(fun)(c1))::5, dec32(unquote(fun)(c2))::5,
-            dec32(unquote(fun)(c3))::5, dec32(unquote(fun)(c4))::5,
-            dec32(unquote(fun)(c5))::5, dec32(unquote(fun)(c6))::5,
-            dec32(unquote(fun)(c7))::5, dec32(unquote(fun)(c8))::5>>
-        <<>> ->
-          <<>>
-      end
-      main <> tail
-    end
-  end
-
-  defp do_decode32(_, _, _),
-    do: raise ArgumentError, "incorrect padding"
-
-  defp do_hex_encode32(_, <<>>, _), do: <<>>
-
-  for {case, fun} <- [upper: :to_upper, lower: :to_lower] do
-    defp do_hex_encode32(unquote(case), data, pad?) do
-      split =  5 * div(byte_size(data), 5)
-      <<main::size(split)-binary, rest::binary>> = data
-      main = for <<c::5 <- main>>, into: <<>>, do: <<unquote(fun)(enc32hex(c))::8>>
-      tail = case rest do
-        <<c1::5, c2::5, c3::5, c4::5, c5::5, c6::5, c7::2>> ->
-          <<unquote(fun)(enc32hex(c1))::8, unquote(fun)(enc32hex(c2))::8,
-            unquote(fun)(enc32hex(c3))::8, unquote(fun)(enc32hex(c4))::8,
-            unquote(fun)(enc32hex(c5))::8, unquote(fun)(enc32hex(c6))::8,
-            unquote(fun)(enc32hex(bsl(c7, 3)))::8>>
-        <<c1::5, c2::5, c3::5, c4::5, c5::4>> ->
-          <<unquote(fun)(enc32hex(c1))::8, unquote(fun)(enc32hex(c2))::8,
-            unquote(fun)(enc32hex(c3))::8, unquote(fun)(enc32hex(c4))::8,
-            unquote(fun)(enc32hex(bsl(c5, 1)))::8>>
-        <<c1::5, c2::5, c3::5, c4::1>> ->
-          <<unquote(fun)(enc32hex(c1))::8, unquote(fun)(enc32hex(c2))::8,
-            unquote(fun)(enc32hex(c3))::8, unquote(fun)(enc32hex(bsl(c4, 4)))::8>>
-        <<c1::5, c2::3>> ->
-          <<unquote(fun)(enc32hex(c1))::8, unquote(fun)(enc32hex(bsl(c2, 2)))::8>>
-        <<>> ->
-          <<>>
-      end
-      main <> maybe_pad(tail, pad?, 8, "=")
-    end
-  end
-
-  defp do_hex_decode32(_, <<>>, _), do: <<>>
-  defp do_hex_decode32(case, string, false),
-    do: do_hex_decode32(case, maybe_pad(string, true, 8, "="), true)
-
-  for {case, fun} <- [upper: :from_upper, lower: :from_lower, mixed: :from_mixed] do
-    defp do_hex_decode32(unquote(case), string, _pad?) when rem(byte_size(string), 8) == 0 do
-      split = byte_size(string) - 8
-      <<main::size(split)-binary, rest::binary>> = string
-      main = for <<c::8 <- main>>, into: <<>>, do: <<dec32hex(unquote(fun)(c))::5>>
-      tail = case rest do
-        <<c1::8, c2::8, ?=, ?=, ?=, ?=, ?=, ?=>> ->
-          <<dec32hex(unquote(fun)(c1))::5, bsr(dec32hex(unquote(fun)(c2)), 2)::3>>
-        <<c1::8, c2::8, c3::8, c4::8, ?=, ?=, ?=, ?=>> ->
-          <<dec32hex(unquote(fun)(c1))::5, dec32hex(unquote(fun)(c2))::5,
-            dec32hex(unquote(fun)(c3))::5, bsr(dec32hex(unquote(fun)(c4)), 4)::1>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, ?=, ?=, ?=>> ->
-          <<dec32hex(unquote(fun)(c1))::5, dec32hex(unquote(fun)(c2))::5,
-            dec32hex(unquote(fun)(c3))::5, dec32hex(unquote(fun)(c4))::5,
-            bsr(dec32hex(unquote(fun)(c5)), 1)::4>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, ?=>> ->
-          <<dec32hex(unquote(fun)(c1))::5, dec32hex(unquote(fun)(c2))::5,
-            dec32hex(unquote(fun)(c3))::5, dec32hex(unquote(fun)(c4))::5,
-            dec32hex(unquote(fun)(c5))::5, dec32hex(unquote(fun)(c6))::5,
-            bsr(dec32hex(unquote(fun)(c7)), 3)::2>>
-        <<c1::8, c2::8, c3::8, c4::8, c5::8, c6::8, c7::8, c8::8>> ->
-          <<dec32hex(unquote(fun)(c1))::5, dec32hex(unquote(fun)(c2))::5,
-            dec32hex(unquote(fun)(c3))::5, dec32hex(unquote(fun)(c4))::5,
-            dec32hex(unquote(fun)(c5))::5, dec32hex(unquote(fun)(c6))::5,
-            dec32hex(unquote(fun)(c7))::5, dec32hex(unquote(fun)(c8))::5>>
-        <<>> ->
-          <<>>
-      end
-      main <> tail
-    end
-  end
-
-  defp do_hex_decode32(_, _, _),
-    do: raise ArgumentError, "incorrect padding"
-end
@@ -1,106 +0,0 @@
-defmodule Behaviour do
-  @moduledoc """
-  This module has been deprecated.
-
-  Instead of `defcallback/1` and `defmacrocallback/1`, the `@callback` and
-  `@macrocallback` module attributes can be used (respectively). See the
-  documentation for `Module` for more information on these attributes.
-
-  Instead of `MyModule.__behaviour__(:callbacks)`,
-  `MyModule.behaviour_info(:callbacks)` can be used.
-  """
-
-  @doc """
-  Defines a function callback according to the given type specification.
-  """
-  defmacro defcallback(spec) do
-    do_defcallback(:def, split_spec(spec, quote(do: term)))
-  end
-
-  @doc """
-  Defines a macro callback according to the given type specification.
-  """
-  defmacro defmacrocallback(spec) do
-    do_defcallback(:defmacro, split_spec(spec, quote(do: Macro.t)))
-  end
-
-  defp split_spec({:when, _, [{:::, _, [spec, return]}, guard]}, _default) do
-    {spec, return, guard}
-  end
-
-  defp split_spec({:when, _, [spec, guard]}, default) do
-    {spec, default, guard}
-  end
-
-  defp split_spec({:::, _, [spec, return]}, _default) do
-    {spec, return, []}
-  end
-
-  defp split_spec(spec, default) do
-    {spec, default, []}
-  end
-
-  defp do_defcallback(kind, {spec, return, guards}) do
-    case Macro.decompose_call(spec) do
-      {name, args} ->
-        do_callback(kind, name, args, return, guards)
-      _ ->
-        raise ArgumentError, "invalid syntax in #{kind}callback #{Macro.to_string(spec)}"
-    end
-  end
-
-  defp do_callback(kind, name, args, return, guards) do
-    :lists.foreach fn
-      {:::, _, [left, right]} ->
-        ensure_not_default(left)
-        ensure_not_default(right)
-        left
-      other ->
-        ensure_not_default(other)
-        other
-    end, args
-
-    spec =
-      quote do
-        unquote(name)(unquote_splicing(args)) :: unquote(return) when unquote(guards)
-      end
-
-    case kind do
-      :def -> quote(do: @callback unquote(spec))
-      :defmacro -> quote(do: @macrocallback unquote(spec))
-    end
-  end
-
-  defp ensure_not_default({:\\, _, [_, _]}) do
-    raise ArgumentError, "default arguments \\\\ not supported in defcallback/defmacrocallback"
-  end
-
-  defp ensure_not_default(_), do: :ok
-
-  @doc false
-  defmacro __using__(_) do
-    quote do
-      warning =
-        "the Behaviour module is deprecated. Instead of using this module, " <>
-        "use the @callback and @macrocallback module attributes. See the " <>
-        "documentation for Module for more information on these attributes"
-      IO.warn(warning)
-
-      @doc false
-      def __behaviour__(:callbacks) do
-        __MODULE__.behaviour_info(:callbacks)
-      end
-
-      def __behaviour__(:docs) do
-        for {tuple, line, kind, docs} <- Code.get_docs(__MODULE__, :callback_docs) do
-          case kind do
-            :callback -> {tuple, line, :def, docs}
-            :macrocallback -> {tuple, line, :defmacro, docs}
-          end
-        end
-      end
-
-      import unquote(__MODULE__)
-    end
-  end
-end
@@ -0,0 +1,218 @@
+defmodule Binary do
+  @moduledoc """
+  Functions for working with binaries.
+  """
+
+  @doc %B"""
+  Receives a char list and escapes all special chars (like \n)
+  and interpolation markers. A last argument is given and wraps
+  the whole char list given.
+
+  ## Examples
+
+      Binary.escape "foo", ?'
+      #=> "'foo'"
+
+  """
+  def escape(other, char) do
+    <<char>> <> do_escape(other, char)
+  end
+
+  @doc """
+  Check if a binary is printable considering it is encoded
+  as UTF-8. Returns true if so, false otherwise.
+
+  ## Examples
+
+      Binary.printable?("abc") #=> true
+
+  """
+
+  # Allow basic ascii chars
+  def printable?(<<c, t|:binary>>) when c in ?\s..?~ do
+    printable?(t)
+  end
+
+  # From 16#A0 to 16#BF
+  def printable?(<<194, c, t|:binary>>) when c in 160..191 do
+    printable?(t)
+  end
+
+  # From 16#C0 to 16#7FF
+  def printable?(<<m, o1, t|:binary>>) when m in 195..223 and o1 in 128..191 do
+    printable?(t)
+  end
+
+  # From 16#800 to 16#CFFF
+  def printable?(<<m, o1, o2, t|:binary>>) when m in 224..236 and
+      o1 >= 128 and o1 < 192 and o2 >= 128 and o2 < 192 do
+    printable?(t)
+  end
+
+  # From 16#D000 to 16#D7FF
+  def printable?(<<237, o1, o2, t|:binary>>) when
+      o1 >= 128 and o1 < 160 and o2 >= 128 and o2 < 192 do
+    printable?(t)
+  end
+
+  # Reject 16#FFFF and 16#FFFE
+  def printable?(<<239, 191, o>>) when o == 190 or o == 191 do
+    false
+  end
+
+  # From 16#E000 to 16#EFFF
+  def printable?(<<m, o1, o2, t|:binary>>) when (m == 238 or m == 239) and
+      o1 in 128..191 and o2 in 128..191 do
+    printable?(t)
+  end
+
+  # From 16#F000 to 16#FFFD
+  def printable?(<<239, o1, o2, t|:binary>>) when
+      o1 in 128..191 and o2 in 128..191 do
+    printable?(t)
+  end
+
+  # From 16#10000 to 16#3FFFF
+  def printable?(<<240, o1, o2, o3, t|:binary>>) when
+      o1 in 144..191 and o2 in 128..191 and o3 in 128..191 do
+    printable?(t)
+  end
+
+  # Reject 16#110000 onwards
+  def printable?(<<244, o1, _, _, _|:binary>>) when o1 >= 144 do
+    false
+  end
+
+  # From 16#4000 to 16#10FFFF
+  def printable?(<<m, o1, o2, o3, t|:binary>>) when m in 241..244 and
+      o1 in 128..191 and o2 in 128..191 and o3 in 128..191 do
+    printable?(t)
+  end
+
+  def printable?(<<?\n, t|:binary>>), do: printable?(t)
+  def printable?(<<?\r, t|:binary>>), do: printable?(t)
+  def printable?(<<?\t, t|:binary>>), do: printable?(t)
+  def printable?(<<?\v, t|:binary>>), do: printable?(t)
+  def printable?(<<?\b, t|:binary>>), do: printable?(t)
+  def printable?(<<?\f, t|:binary>>), do: printable?(t)
+  def printable?(<<?\e, t|:binary>>), do: printable?(t)
+
+  def printable?(<<>>), do: true
+  def printable?(_),    do: false
+
+  @doc %B"""
+  Unescape the given chars. The unescaping is driven by the same
+  rules as single- and double-quoted strings. Check `unescape/2`
+  for information on how to customize the escaping map.
+
+  In this setup, Elixir will escape the following: `\b`, `\d`,
+  `\e`, `\f`, `\n`, `\r`, `\s`, `\t` and `\v`. Octals are also
+  escaped according to the latin1 set they represent.
+
+  ## Examples
+
+      Binary.unescape "example\\n"
+      #=> "example\n"
+
+  In the example above, we pass a string with `\n` escaped
+  and we return a version with it unescaped.
+  """
+  def unescape(chars) do
+    Erlang.elixir_interpolation.unescape_chars(chars)
+  end
+
+  @doc %B"""
+  Unescape the given chars according to the map given.
+  Check `unescape/1` if you want to use the same map as Elixir
+  single- and double-quoted strings.
+
+  ## Map
+
+  The map must be a function. The function receives an integer
+  representing the number of the characters it wants to unescape.
+  Here is the default mapping function implemented by Elixir:
+
+      def unescape_map(?b), do: ?\b
+      def unescape_map(?d), do: ?\d
+      def unescape_map(?e), do: ?\e
+      def unescape_map(?f), do: ?\f
+      def unescape_map(?n), do: ?\n
+      def unescape_map(?r), do: ?\r
+      def unescape_map(?s), do: ?\s
+      def unescape_map(?t), do: ?\t
+      def unescape_map(?v), do: ?\v
+      def unescape_map(e), do: e
+
+  If the `unescape_map` function returns false. The char is
+  not escaped and `\` is kept in the char list.
+
+  ## Octals
+
+  Octals will by default be escaped unless the map function
+  returns false for ?0.
+
+  ## Examples
+
+  Using the unescape_map defined above is easy:
+
+      Binary.unescape "example\\n", unescape_map(&1)
+
+  """
+  def unescape(chars, map) do
+    Erlang.elixir_interpolation.unescape_chars(chars, map)
+  end
+
+  @doc """
+  Unescape the given tokens according to the default map.
+  Check `unescape/1` and `unescape/2` for more information
+  about unescaping. Only tokens that are char lists are
+  unescaped, all others are ignored. This method is useful
+  when implementing your own sigils. Check the implementation
+  of `Kernel.__b__` for examples.
+  """
+  def unescape_tokens(tokens) do
+    Erlang.elixir_interpolation.unescape_tokens(tokens)
+  end
+
+  @doc """
+  Unescape the given tokens according to the given map.
+  Check `unescape_tokens/1` and `unescaped/2` for more information.
+  """
+  def unescape_tokens(tokens, map) do
+    Erlang.elixir_interpolation.unescape_tokens(tokens, map)
+  end
+
+  ## Helpers
+
+  defp do_escape(<<char, t|:binary>>, char) do
+    <<?\\, char, do_escape(t, char)|:binary>>
+  end
+
+  defp do_escape(<<h, t|:binary>>, char) when
+    h == ?#  or h == ?\b or
+    h == ?\d or h == ?\e or
+    h == ?\f or h == ?\n or
+    h == ?\r or h == ?\\ or
+    h == ?\t or h == ?\v do
+    <<?\\, escape_map(h), do_escape(t, char)|:binary>>
+  end
+
+  defp do_escape(<<h, t|:binary>>, char) do
+    <<h, do_escape(t,char)|:binary>>
+  end
+
+  defp do_escape(<<>>, char) do
+    <<char>>
+  end
+
+  defp escape_map(?#),  do: ?#
+  defp escape_map(?\b), do: ?b
+  defp escape_map(?\d), do: ?d
+  defp escape_map(?\e), do: ?e
+  defp escape_map(?\f), do: ?f
+  defp escape_map(?\n), do: ?n
+  defp escape_map(?\r), do: ?r
+  defp escape_map(?\\), do: ?\\
+  defp escape_map(?\t), do: ?t
+  defp escape_map(?\v), do: ?v
+end
@@ -0,0 +1,74 @@
+import Kernel, except: [to_binary: 1]
+
+defprotocol Binary.Chars do
+  @moduledoc %B"""
+  The Binary.Chars protocol is responsible for
+  converting a structure to a Binary (only if applicable).
+  The only function required to be implemented is
+  `to_binary` which does the conversion.
+
+  The `to_binary` function automatically imported
+  by Kernel invokes this protocol. String
+  interpolation also invokes to_binary in its
+  arguments. For example, `"foo#{bar}"` is the same
+  as `"foo" <> to_binary(bar)`.
+  """
+
+  @only [BitString, List, Number, Atom, Record]
+
+  def to_binary(thing)
+end
+
+defimpl Binary.Chars, for: Atom do
+  @doc """
+  Convert the atom literally to a binary, except
+  `nil` which is converted to an empty string.
+  """
+  def to_binary(nil) do
+    ""
+  end
+
+  def to_binary(atom) do
+    atom_to_binary(atom, :utf8)
+  end
+end
+
+defimpl Binary.Chars, for: BitString do
+  @doc """
+  Simply returns the binary itself.
+  """
+  def to_binary(thing) when is_binary(thing) do
+    thing
+  end
+end
+
+defimpl Binary.Chars, for: List do
+  @doc """
+  Consider the list is an iolist and converts it
+  to a binary. This allows a list of binaries, or
+  a charlist, or a mix of both, to be converted
+  successfully.
+
+  ## Examples
+
+      to_binary 'foo' #=> "foo"
+      to_binary ["foo", 'bar'] #=> "foobar"
+
+  """
+  def to_binary(thing) do
+    iolist_to_binary(thing)
+  end
+end
+
+defimpl Binary.Chars, for: Number do
+  @doc """
+  Simply converts the number (integer or a float) to a binary.
+  """
+  def to_binary(thing) when is_integer(thing) do
+    list_to_binary integer_to_list(thing)
+  end
+
+  def to_binary(thing) do
+    list_to_binary float_to_list(thing)
+  end
+end
@@ -0,0 +1,301 @@
+import Kernel, except: [inspect: 1]
+
+defprotocol Binary.Inspect do
+  @moduledoc """
+  The `Binary.Inspect` protocol is responsible for
+  converting any structure to a Binary for textual
+  representation. All basic data structures (tuple,
+  list, function, pid, etc) implement the inspect
+  protocol. Other structures are adviced to implement
+  the protocol in order to provide pretty printing.
+  """
+
+  @only [BitString, List, Record, Tuple, Atom, Number, Any]
+
+  def inspect(thing)
+end
+
+defimpl Binary.Inspect, for: Atom do
+  require Macro
+
+  @doc """
+  Represents the atom as an Elixir term. The atoms false, true
+  and nil are simply quoted. Modules are properly represented
+  as modules using the dot notation.
+
+  Notice that in Elixir, all operators can be represented using
+  literal atoms (`:+`, `:-`, etc).
+
+  ## Examples
+
+      inspect(:foo)    #=> ":foo"
+      inspect(nil)     #=> "nil"
+      inspect(Foo.Bar) #=> "Foo.Bar"
+
+  """
+  def inspect(false),  do: "false"
+  def inspect(true),   do: "true"
+  def inspect(nil),    do: "nil"
+  def inspect(:""),    do: ":\"\""
+  def inspect(Elixir), do: "Elixir"
+
+  def inspect(atom) do
+    binary = atom_to_binary(atom)
+
+    cond do
+      valid_atom_identifier?(binary) ->
+        ":" <> binary
+      valid_ref_identifier?(binary) ->
+        "Elixir-" <> rest = binary
+        bc <<r>> inbits rest, do: <<to_dot(r)>>
+      atom in Macro.binary_ops or atom in Macro.unary_ops ->
+        ":" <> binary
+      true ->
+        ":" <> Binary.escape(binary, ?")
+    end
+  end
+
+  # Detect if atom is an atom alias (Elixir-Foo-Bar-Baz)
+
+  defp to_dot(?-), do: ?.
+  defp to_dot(l),  do: l
+
+  defp valid_ref_identifier?("Elixir" <> rest) do
+    valid_ref_piece?(rest)
+  end
+
+  defp valid_ref_identifier?(_), do: false
+
+  defp valid_ref_piece?(<<?-, h, t|:binary>>) when h in ?A..?Z do
+    valid_ref_piece? valid_identifier?(t)
+  end
+
+  defp valid_ref_piece?(<<>>), do: true
+  defp valid_ref_piece?(_),    do: false
+
+  # Detect if atom
+
+  defp valid_atom_identifier?(<<h, t|:binary>>) when h in ?a..?z or h in ?A..?Z or h == ?_ do
+    case valid_identifier?(t) do
+      <<>>   -> true
+      <<??>> -> true
+      <<?!>> -> true
+      _      -> false
+    end
+  end
+
+  defp valid_atom_identifier?(_), do: false
+
+  defp valid_identifier?(<<h, t|:binary>>)
+      when h in ?a..?z
+      when h in ?A..?Z
+      when h in ?0..?9
+      when h == ?_ do
+    valid_identifier? t
+  end
+
+  defp valid_identifier?(other), do: other
+end
+
+defimpl Binary.Inspect, for: BitString do
+  @doc %B"""
+  Represents the string as itself escaping
+  all necessary characters.
+
+  ## Examples
+
+      inspect("bar")   #=> "bar"
+      inspect("f\"oo") #=> "f\"oo"
+
+  """
+  def inspect(thing) when is_binary(thing) do
+    if Binary.printable?(thing) do
+      Binary.escape(thing, ?")
+    else
+      as_bitstring(thing)
+    end
+  end
+
+  def inspect(thing) do
+    as_bitstring(thing)
+  end
+
+  ## Helpers
+
+  defp as_bitstring(thing) do
+    erlang = Erlang.io_lib.format('~p', [thing])
+    list_to_binary List.reverse(replace(erlang, []))
+  end
+
+  defp replace([?:|t], acc),                do: replace(t, [?||acc])
+  defp replace([h|t], acc) when is_list(h), do: replace(t, replace(h, acc))
+  defp replace([h|t], acc),                 do: replace(t, [h|acc])
+  defp replace([], acc),                    do: acc
+end
+
+defimpl Binary.Inspect, for: List do
+
+  @doc %B"""
+  Represents a list checking if it can be printed or not.
+  If so, a single-quoted representation is returned,
+  otherwise the brackets syntax is used.
+
+  Inspecting a list is conservative as it does not try
+  to guess how the list is encoded. That said, `'josé'`
+  will likely be inspected as `[106,111,115,195,169]`
+  because we can't know if it is encoded in utf-8
+  or iso-5569-1, which is common in Erlang libraries.
+
+  ## Examples
+
+      inspect('bar')       #=> 'bar'
+      inspect([0|'bar'])   #=> "[0,98,97,114]"
+      inspect([:foo,:bar]) #=> "[:foo, :bar]"
+
+  """
+
+  def inspect([]), do: "[]"
+
+  def inspect(thing) do
+    if printable?(thing) do
+      Binary.escape(list_to_binary(thing), ?')
+    else
+      container_join(thing, "[", "]")
+    end
+  end
+
+  ## Helpers
+
+  def container_join([h], acc, last) do
+    acc <> Binary.Inspect.inspect(h) <> last
+  end
+
+  def container_join([h|t], acc, last) when is_list(t) do
+    acc = acc <> Binary.Inspect.inspect(h) <> ","
+    container_join(t, acc, last)
+  end
+
+  def container_join([h|t], acc, last) do
+    acc <> Binary.Inspect.inspect(h) <> "|" <> Binary.Inspect.inspect(t) <> last
+  end
+
+  def container_join([], acc, last) do
+    acc <> last
+  end
+
+  ## printable?
+
+  defp printable?([c|cs]) when is_integer(c) and c in 32..126 do
+    printable?(cs)
+  end
+
+  defp printable?([c|cs]) when c in [?\n, ?\r, ?\t, ?\v, ?\b, ?\f, ?\e] do
+    printable?(cs)
+  end
+
+  defp printable?([]), do: true
+  defp printable?(_),  do: false
+end
+
+defimpl Binary.Inspect, for: Tuple do
+  @doc """
+  Inspect tuples. If the tuple represents a record,
+  it shows it nicely formatted using the access syntax.
+
+  ## Examples
+
+      inspect({1,2,3})            #=> "{1,2,3}"
+      inspect(ArgumentError.new)  #=> ArgumentError[message: "argument error"]
+
+  """
+  def inspect({}), do: "{}"
+
+  def inspect(exception) when is_exception(exception) do
+    [name,_|tail] = tuple_to_list(exception)
+    [_|fields]    = lc { field, _ } inlist name.__record__(:fields), do: field
+    Binary.Inspect.Atom.inspect(name) <> records_join(fields, tail, "[", "]")
+  end
+
+  def inspect(thing) do
+    list = tuple_to_list(thing)
+    [name|tail] = list
+
+    if is_record?(name) do
+      fields = lc { field, _ } inlist name.__record__(:fields), do: field
+      if length(fields) != size(thing) - 1 do
+        Binary.Inspect.List.container_join(list, "{", "}")
+      else
+        Binary.Inspect.Atom.inspect(name) <> records_join(fields, tail, "[", "]")
+      end
+    else
+      Binary.Inspect.List.container_join(list, "{", "}")
+    end
+  end
+
+  ## Helpers
+
+  defp is_record?(name) do
+    is_atom(name) and match?("Elixir-" <> _, atom_to_binary(name, :utf8)) and
+      function_exported?(name, :__record__, 1)
+  end
+
+  defp records_join([f], [v], acc, last) do
+    acc <> atom_to_binary(f, :utf8) <> ": " <> Binary.Inspect.inspect(v) <> last
+  end
+
+  defp records_join([fh|ft], [vh|vt], acc, last) do
+    acc = acc <> atom_to_binary(fh, :utf8) <> ": " <> Binary.Inspect.inspect(vh) <> ", "
+    records_join(ft, vt, acc, last)
+  end
+
+  defp records_join([], [], acc, last) do
+    acc <> last
+  end
+end
+
+defimpl Binary.Inspect, for: Number do
+  @doc """
+  Represents the number as a binary.
+
+  ## Examples
+
+      inspect(1) #=> "1"
+
+  """
+  def inspect(thing) when is_integer(thing) do
+    list_to_binary integer_to_list(thing)
+  end
+
+  def inspect(thing) do
+    list_to_binary float_to_list(thing)
+  end
+end
+
+defimpl Binary.Inspect, for: Regex do
+  @doc %B"""
+  Represents the Regex using the `%r""` syntax.
+
+  ## Examples
+
+      inspect(%r/foo/m) #=> "%r\"foo\"m"
+
+  """
+  def inspect(thing) do
+    "%r" <> Binary.Inspect.inspect(Regex.source(thing)) <> Regex.opts(thing)
+  end
+end
+
+defimpl Binary.Inspect, for: Any do
+  @doc """
+  For all other terms not implemented, we use the default
+  Erlang representation.
+
+  ## Examples
+
+      inspect Process.self #=> "<0.35.0>"
+
+  """
+  def inspect(thing) do
+    iolist_to_binary Erlang.io_lib.format('~p', [thing])
+  end
+end
@@ -1,49 +1,38 @@
 defmodule Bitwise do
  @moduledoc """
-  A set of macros that perform calculations on bits.
+  This module provide macros and operators for bitwise operators.
+  These macros can be used in guards.

-  The macros in this module come in two flavors: named or
-  operators. For example:
+  The easiest way to use is to simply import them into
+  your module:

-      iex> use Bitwise
-      iex> bnot 1   # named
-      -2
-      iex> 1 &&& 1  # operator
-      1
+      use Bitwise

-  If you prefer to use only operators or skip them, you can
-  pass the following options:
+      bnot 1   #=> -2
+      1 &&& 1  #=> 1

-    * `:only_operators` - includes only operators
-    * `:skip_operators` - skips operators
+  You can select to include only or skip operators by passing options:

-  For example:
-
-      iex> use Bitwise, only_operators: true
-      iex> 1 &&& 1
-      1
-
-  When invoked with no options, `use Bitwise` is equivalent
-  to `import Bitwise`.
-
-  All bitwise macros can be used in guards:
-
-      iex> use Bitwise
-      iex> odd? = fn int when band(int, 1) == 1 -> true; _ -> false end
-      iex> odd?.(1)
-      true
+      use Bitwise, only_operators: true
+      1 &&& 1 #=> 1

  """

-  @doc false
+  @doc """
+  Allow a developer to use this module in their programs with
+  the following options:
+
+  * `:only_operators` - Include only operators;
+  * `:skip_operators` - Skip operators;
+
+  """
  defmacro __using__(options) do
    except = cond do
      Keyword.get(options, :only_operators) ->
-        [bnot: 1, band: 2, bor: 2, bxor: 2, bsl: 2, bsr: 2]
+        [:bnot, :band, :bor, :bxor, :bsl, :bsr]
      Keyword.get(options, :skip_operators) ->
-        [~~~: 1, &&&: 2, |||: 2, ^^^: 2, <<<: 2, >>>: 2]
-      true ->
-        []
+        [:~~~, :&&&, :|||, :^^^, :<<<, :>>>]
+      true -> []
    end

    quote do
@@ -52,162 +41,86 @@ defmodule Bitwise do
  end

  @doc """
-  Calculates the bitwise NOT of its argument.
-
-      iex> bnot(2)
-      -3
-      iex> bnot(2) &&& 3
-      1
-
+  Bitwise not.
  """
  defmacro bnot(expr) do
-    quote do: :erlang.bnot(unquote(expr))
+    quote do: __op__ :bnot, unquote(expr)
  end

  @doc """
-  Prefix (unary) operator; calculates the bitwise NOT of its argument.
-
-      iex> ~~~2
-      -3
-      iex> ~~~2 &&& 3
-      1
-
+  Bitwise not as operator.
  """
  defmacro ~~~expr do
-    quote do: :erlang.bnot(unquote(expr))
+    quote do: __op__ :bnot, unquote(expr)
  end

  @doc """
-  Calculates the bitwise AND of its arguments.
-
-      iex> band(9, 3)
-      1
-
+  Bitwise and.
  """
  defmacro band(left, right) do
-    quote do: :erlang.band(unquote(left), unquote(right))
+    quote do: __op__ :band, unquote(left), unquote(right)
  end

  @doc """
-  Infix operator; calculates the bitwise AND of its arguments.
-
-      iex> 9 &&& 3
-      1
-
+  Bitwise and as operator.
  """
  defmacro left &&& right do
-    quote do: :erlang.band(unquote(left), unquote(right))
+    quote do: __op__ :band, unquote(left), unquote(right)
  end

  @doc """
-  Calculates the bitwise OR of its arguments.
-
-      iex> bor(9, 3)
-      11
-
+  Bitwise or.
  """
  defmacro bor(left, right) do
-    quote do: :erlang.bor(unquote(left), unquote(right))
+    quote do: __op__ :bor, unquote(left), unquote(right)
  end

  @doc """
-  Infix operator; calculates the bitwise OR of its arguments.
-
-      iex> 9 ||| 3
-      11
-
+  Bitwise or as operator.
  """
  defmacro left ||| right do
-    quote do: :erlang.bor(unquote(left), unquote(right))
+    quote do: __op__ :bor, unquote(left), unquote(right)
  end

  @doc """
-  Calculates the bitwise XOR of its arguments.
-
-      iex> bxor(9, 3)
-      10
-
+  Bitwise xor.
  """
  defmacro bxor(left, right) do
-    quote do: :erlang.bxor(unquote(left), unquote(right))
+    quote do: __op__ :bxor, unquote(left), unquote(right)
  end

  @doc """
-  Infix operator; calculates the bitwise XOR of its arguments.
-
-      iex> 9 ^^^ 3
-      10
-
+  Bitwise xor as operator.
  """
  defmacro left ^^^ right do
-    quote do: :erlang.bxor(unquote(left), unquote(right))
+    quote do: __op__ :bxor, unquote(left), unquote(right)
  end

  @doc """
-  Calculates the result of an arithmetic left bitshift.
-
-      iex> bsl(1, 2)
-      4
-      iex> bsl(1, -2)
-      0
-      iex> bsl(-1, 2)
-      -4
-      iex> bsl(-1, -2)
-      -1
-
+  Arithmetic bitshift left.
  """
  defmacro bsl(left, right) do
-    quote do: :erlang.bsl(unquote(left), unquote(right))
+    quote do: __op__ :bsl, unquote(left), unquote(right)
  end

  @doc """
-  Infix operator; calculates the result of an arithmetic left bitshift.
-
-      iex> 1 <<< 2
-      4
-      iex> 1 <<< -2
-      0
-      iex> -1 <<< 2
-      -4
-      iex> -1 <<< -2
-      -1
-
+  Arithmetic bitshift left as operator.
  """
  defmacro left <<< right do
-    quote do: :erlang.bsl(unquote(left), unquote(right))
+    quote do: __op__ :bsl, unquote(left), unquote(right)
  end

  @doc """
-  Calculates the result of an arithmetic right bitshift.
-
-      iex> bsr(1, 2)
-      0
-      iex> bsr(1, -2)
-      4
-      iex> bsr(-1, 2)
-      -1
-      iex> bsr(-1, -2)
-      -4
-
+  Arithmetic bitshift right.
  """
  defmacro bsr(left, right) do
-    quote do: :erlang.bsr(unquote(left), unquote(right))
+    quote do: __op__ :bsr, unquote(left), unquote(right)
  end

  @doc """
-  Infix operator; calculates the result of an arithmetic right bitshift.
-
-      iex> 1 >>> 2
-      0
-      iex> 1 >>> -2
-      4
-      iex> -1 >>> 2
-      -1
-      iex> -1 >>> -2
-      -4
-
+  Arithmetic bitshift right as operator.
  """
  defmacro left >>> right do
-    quote do: :erlang.bsr(unquote(left), unquote(right))
+    quote do: __op__ :bsr, unquote(left), unquote(right)
  end
-end
+end
@@ -1,262 +0,0 @@
-defmodule Calendar.ISO do
-  @moduledoc """
-  A calendar implementation that follows to ISO8601.
-
-  This calendar implements the proleptic Gregorian calendar and
-  is therefore compatible with the calendar used in most countries
-  today. The proleptic means the Gregorian rules for leap years are
-  applied for all time, consequently the dates give different results
-  before the year 1583 from when the Gregorian calendar was adopted.
-  """
-
-  @behaviour Calendar
-  @unix_epoch :calendar.datetime_to_gregorian_seconds {{1970, 1, 1}, {0, 0, 0}}
-
-  @type year  :: 0..9999
-  @type month :: 1..12
-  @type day   :: 1..31
-
-  @doc """
-  Returns how many days there are in the given year-month.
-
-  ## Examples
-
-      iex> Calendar.ISO.days_in_month(1900, 1)
-      31
-      iex> Calendar.ISO.days_in_month(1900, 2)
-      28
-      iex> Calendar.ISO.days_in_month(2000, 2)
-      29
-      iex> Calendar.ISO.days_in_month(2001, 2)
-      28
-      iex> Calendar.ISO.days_in_month(2004, 2)
-      29
-      iex> Calendar.ISO.days_in_month(2004, 4)
-      30
-
-  """
-  @spec days_in_month(year, month) :: 28..31
-  def days_in_month(year, month)
-
-  def days_in_month(year, 2) do
-    if leap_year?(year), do: 29, else: 28
-  end
-  def days_in_month(_, month) when month in [4, 6, 9, 11], do: 30
-  def days_in_month(_, month) when month in 1..12, do: 31
-
-  @doc """
-  Returns if the given year is a leap year.
-
-  ## Examples
-
-      iex> Calendar.ISO.leap_year?(2000)
-      true
-      iex> Calendar.ISO.leap_year?(2001)
-      false
-      iex> Calendar.ISO.leap_year?(2004)
-      true
-      iex> Calendar.ISO.leap_year?(1900)
-      false
-
-  """
-  @spec leap_year?(year) :: boolean()
-  def leap_year?(year) when is_integer(year) and year >= 0 do
-    rem(year, 4) === 0 and (rem(year, 100) > 0 or rem(year, 400) === 0)
-  end
-
-  @doc """
-  Calculates the day of the week from the given `year`, `month`, and `day`.
-
-  It is an integer from 1 to 7, where 1 is Monday and 7 is Sunday.
-
-  ## Examples
-
-      iex> Calendar.ISO.day_of_week(2016, 10, 31)
-      1
-      iex> Calendar.ISO.day_of_week(2016, 11, 01)
-      2
-      iex> Calendar.ISO.day_of_week(2016, 11, 02)
-      3
-      iex> Calendar.ISO.day_of_week(2016, 11, 03)
-      4
-      iex> Calendar.ISO.day_of_week(2016, 11, 04)
-      5
-      iex> Calendar.ISO.day_of_week(2016, 11, 05)
-      6
-      iex> Calendar.ISO.day_of_week(2016, 11, 06)
-      7
-  """
-  @spec day_of_week(year, month, day) :: 1..7
-  def day_of_week(year, month, day)
-      when is_integer(year) and is_integer(month) and is_integer(day) do
-    :calendar.day_of_the_week(year, month, day)
-  end
-
-  @doc """
-  Converts the given date into a string.
-  """
-  def date_to_string(year, month, day) do
-    zero_pad(year, 4) <> "-" <> zero_pad(month, 2) <> "-" <> zero_pad(day, 2)
-  end
-
-  @doc """
-  Converts the datetime (without time zone) into a string.
-  """
-  def naive_datetime_to_string(year, month, day, hour, minute, second, microsecond) do
-    date_to_string(year, month, day) <> " " <> time_to_string(hour, minute, second, microsecond)
-  end
-
-  @doc """
-  Convers the datetime (with time zone) into a string.
-  """
-  def datetime_to_string(year, month, day, hour, minute, second, microsecond,
-                         time_zone, zone_abbr, utc_offset, std_offset) do
-    date_to_string(year, month, day) <> " " <>
-      time_to_string(hour, minute, second, microsecond) <>
-      offset_to_string(utc_offset, std_offset, time_zone) <>
-      zone_to_string(utc_offset, std_offset, zone_abbr, time_zone)
-  end
-
-  defp offset_to_string(0, 0, "Etc/UTC"), do: "Z"
-  defp offset_to_string(utc, std, _zone) do
-    total  = utc + std
-    second = abs(total)
-    minute = second |> rem(3600) |> div(60)
-    hour   = second |> div(3600)
-    sign(total) <> zero_pad(hour, 2) <> ":" <> zero_pad(minute, 2)
-  end
-
-  defp zone_to_string(0, 0, _abbr, "Etc/UTC"), do: ""
-  defp zone_to_string(_, _, abbr, zone), do: " " <> abbr <> " " <> zone
-
-  defp sign(total) when total < 0, do: "-"
-  defp sign(_), do: "+"
-
-  defp zero_pad(val, count) do
-    num = Integer.to_string(val)
-    :binary.copy("0", count - byte_size(num)) <> num
-  end
-
-  ## Helpers
-
-  @doc false
-  def time_to_string(hour, minute, second, {_, 0}) do
-    time_to_string(hour, minute, second)
-  end
-  def time_to_string(hour, minute, second, {microsecond, precision}) do
-    time_to_string(hour, minute, second) <> "." <>
-      (microsecond |> zero_pad(6) |> binary_part(0, precision))
-  end
-  defp time_to_string(hour, minute, second) do
-    zero_pad(hour, 2) <> ":" <> zero_pad(minute, 2) <> ":" <> zero_pad(second, 2)
-  end
-
-  @doc false
-  def date(year, month, day) when is_integer(year) and is_integer(month) and is_integer(day) do
-    if :calendar.valid_date(year, month, day) and year <= 9999 do
-      {:ok, %Date{year: year, month: month, day: day}}
-    else
-      {:error, :invalid_date}
-    end
-  end
-
-  @doc false
-  def from_unix(integer, unit) when is_integer(integer) do
-    total = System.convert_time_unit(integer, unit, :microsecond)
-    if total < -@unix_epoch * 1_000_000 do
-      {:error, :invalid_unix_time}
-    else
-      microsecond = rem(total, 1_000_000)
-      precision = precision_for_unit(unit)
-      {date, time} = :calendar.gregorian_seconds_to_datetime(@unix_epoch + div(total, 1_000_000))
-      {:ok, date, time, {microsecond, precision}}
-    end
-  end
-
-  defp precision_for_unit(unit) do
-    subsecond = div System.convert_time_unit(1, :second, unit), 10
-    precision_for_unit(subsecond, 0)
-  end
-
-  defp precision_for_unit(0, precision),
-    do: precision
-  defp precision_for_unit(_, 6),
-    do: 6
-  defp precision_for_unit(number, precision),
-    do: precision_for_unit(div(number, 10), precision + 1)
-
-  @doc false
-  def date_to_iso8601(year, month, day) do
-    date_to_string(year, month, day)
-  end
-
-  @doc false
-  def time_to_iso8601(hour, minute, second, microsecond) do
-    time_to_string(hour, minute, second, microsecond)
-  end
-
-  @doc false
-  def naive_datetime_to_iso8601(year, month, day, hour, minute, second, microsecond) do
-    date_to_string(year, month, day) <> "T" <> time_to_string(hour, minute, second, microsecond)
-  end
-
-  @doc false
-  def datetime_to_iso8601(year, month, day, hour, minute, second, microsecond,
-                          time_zone, _zone_abbr, utc_offset, std_offset) do
-    date_to_string(year, month, day) <> "T" <>
-      time_to_string(hour, minute, second, microsecond) <>
-      offset_to_string(utc_offset, std_offset, time_zone)
-  end
-
-  @doc false
-  def parse_microsecond("." <> rest) do
-    case parse_microsecond(rest, 0, "") do
-      {"", 0, _} ->
-        :error
-      {microsecond, precision, rest} when precision in 1..6 ->
-        pad = String.duplicate("0", 6 - byte_size(microsecond))
-        {{String.to_integer(microsecond <> pad), precision}, rest}
-      {microsecond, _precision, rest} ->
-        {{String.to_integer(binary_part(microsecond, 0, 6)), 6}, rest}
-    end
-  end
-  def parse_microsecond(rest) do
-    {{0, 0}, rest}
-  end
-
-  defp parse_microsecond(<<h, t::binary>>, precision, acc) when h in ?0..?9,
-    do: parse_microsecond(t, precision + 1, <<acc::binary, h>>)
-  defp parse_microsecond(rest, precision, acc),
-    do: {acc, precision, rest}
-
-  @doc false
-  def parse_offset(""),
-    do: {nil, ""}
-  def parse_offset("Z"),
-    do: {0, ""}
-  def parse_offset("-00:00"),
-    do: :error
-  def parse_offset(<<?+, hour::2-bytes, ?:, min::2-bytes, rest::binary>>),
-    do: parse_offset(1, hour, min, rest)
-  def parse_offset(<<?-, hour::2-bytes, ?:, min::2-bytes, rest::binary>>),
-    do: parse_offset(-1, hour, min, rest)
-  def parse_offset(<<?+, hour::2-bytes, min::2-bytes, rest::binary>>),
-    do: parse_offset(1, hour, min, rest)
-  def parse_offset(<<?-, hour::2-bytes, min::2-bytes, rest::binary>>),
-    do: parse_offset(-1, hour, min, rest)
-  def parse_offset(<<?+, hour::2-bytes, rest::binary>>),
-    do: parse_offset(1, hour, "00", rest)
-  def parse_offset(<<?-, hour::2-bytes, rest::binary>>),
-    do: parse_offset(-1, hour, "00", rest)
-  def parse_offset(_),
-    do: :error
-
-  defp parse_offset(sign, hour, min, rest) do
-    with {hour, ""} when hour < 24 <- Integer.parse(hour),
-         {min, ""} when min < 60 <- Integer.parse(min) do
-      {((hour * 60) + min) * 60 * sign, rest}
-    else
-      _ -> :error
-    end
-  end
-end
@@ -1,683 +1,314 @@
 defmodule Code do
  @moduledoc """
-  Utilities for managing code compilation, code evaluation and code loading.
+  The Code module is responsible to manage code compilation,
+  code evaluation and code loading.
+
+  It complements (Erlang's code module)[1] to add behavior
+  which is specific to Elixir.
+
+    [1]: (www.erlang.org/doc/man/code.html)

-  This module complements Erlang's [`:code` module](http://www.erlang.org/doc/man/code.html)
-  to add behaviour which is specific to Elixir. Almost all of the functions in this module
-  have global side effects on the behaviour of Elixir.
  """

  @doc """
-  Lists all loaded files.
-
-  ## Examples
-
-      Code.require_file("../eex/test/eex_test.exs")
-      List.first(Code.loaded_files) =~ "eex_test.exs" #=> true
-
+  Returns all the loaded files.
  """
  def loaded_files do
-    :elixir_code_server.call :loaded
+    server_call :loaded
  end

  @doc """
-  Removes files from the loaded files list.
-
-  The modules defined in the file are not removed;
-  calling this function only removes them from the list,
-  allowing them to be required again.
-
-  ## Examples
-
-      # Load EEx test code, unload file, check for functions still available
-      Code.load_file("../eex/test/eex_test.exs")
-      Code.unload_files(Code.loaded_files)
-      function_exported?(EExTest.Compiled, :before_compile, 0) #=> true
-
-  """
-  def unload_files(files) do
-    :elixir_code_server.cast {:unload_files, files}
-  end
-
-  @doc """
-  Appends a path to the end of the Erlang VM code path list.
-
-  This is the list of directories the Erlang VM uses for
-  finding module code.
-
-  The path is expanded with `Path.expand/1` before being appended.
-  If this path does not exist, an error is returned.
-
-  ## Examples
-
-      Code.append_path(".") #=> true
-
-      Code.append_path("/does_not_exist") #=> {:error, :bad_directory}
-
+  Appends a path to Erlang VM code path.
+  The path is expanded with `File.expand_path` before added.
  """
  def append_path(path) do
-    :code.add_pathz(to_charlist(Path.expand path))
+    Erlang.code.add_pathz(File.expand_path to_char_list(path))
  end

  @doc """
-  Prepends a path to the beginning of the Erlang VM code path list.
-
-  This is the list of directories the Erlang VM uses for finding
-  module code.
-
-  The path is expanded with `Path.expand/1` before being prepended.
-  If this path does not exist, an error is returned.
-
-  ## Examples
-
-      Code.prepend_path(".") #=> true
-
-      Code.prepend_path("/does_not_exist") #=> {:error, :bad_directory}
-
+  Prepends a path to Erlang VM code path.
+  The path is expanded with `File.expand_path` before added.
  """
  def prepend_path(path) do
-    :code.add_patha(to_charlist(Path.expand path))
+    Erlang.code.add_patha(File.expand_path to_char_list(path))
  end

  @doc """
-  Deletes a path from the Erlang VM code path list. This is the list of
-  directories the Erlang VM uses for finding module code.
+  Evalutes the contents given by string. The second argument is the binding
+  (which should be a Keyword) followed by a keyword list of options. The
+  options can be:

-  The path is expanded with `Path.expand/1` before being deleted. If the
-  path does not exist it returns `false`.
+  * `:file` - the file to be considered in the evaluation
+  * `:line` - the line the script starts
+  * `:delegate_locals_to` - delegate local calls to the given module,
+    otherwise functions are evaluated inside Erlang's default scope.

  ## Examples

-      Code.prepend_path(".")
-      Code.delete_path(".") #=> true
+      Code.eval "a + b", [a: 1, b: 2], file: __ENV__.file, line: __ENV__.line
+      #=> { 3, [ {:a, 1}, {:b, 2} ] }

-      Code.delete_path("/does_not_exist") #=> false
+  When passing the __ENV__'s file and line, we could simply get
+  the location which already returns both fields as a keywords lists:
+
+      Code.eval "a + b", [a: 1, b: 2], __ENV__.location
+      #=> { 3, [ {:a, 1}, {:b, 2} ] }

  """
-  def delete_path(path) do
-    :code.del_path(to_charlist(Path.expand path))
+  def eval(string, binding // [], opts // []) do
+    { value, binding, _scope } =
+      Erlang.elixir.eval :unicode.characters_to_list(string), binding, opts
+    { value, binding }
  end

  @doc """
-  Evaluates the contents given by `string`.
-
-  The `binding` argument is a keyword list of variable bindings.
-  The `opts` argument is a keyword list of environment options.
+  Evalutes the quoted contents.

  ## Options

-  Options can be:
+  This function accepts a list of options. The supported
+  options are:

-    * `:file` - the file to be considered in the evaluation
-    * `:line` - the line on which the script starts
+  * `:file` - The filename to be used in stacktraces
+    and the file reported in the __ENV__ variable.

-  Additionally, the following scope values can be configured:
-
-    * `:aliases` - a list of tuples with the alias and its target
-
-    * `:requires` - a list of modules required
-
-    * `:functions` - a list of tuples where the first element is a module
-      and the second a list of imported function names and arity; the list
-      of function names and arity must be sorted
-
-    * `:macros` - a list of tuples where the first element is a module
-      and the second a list of imported macro names and arity; the list
-      of function names and arity must be sorted
-
-  Notice that setting any of the values above overrides Elixir's default
-  values. For example, setting `:requires` to `[]`, will no longer
-  automatically require the `Kernel` module; in the same way setting
-  `:macros` will no longer auto-import `Kernel` macros like `if/2`, `case/2`,
-  etc.
-
-  Returns a tuple of the form `{value, binding}`,
-  where `value` is the value returned from evaluating `string`.
-  If an error occurs while evaluating `string` an exception will be raised.
-
-  `binding` is a keyword list with the value of all variable bindings
-  after evaluating `string`. The binding key is usually an atom, but it
-  may be a tuple for variables defined in a different context.
+  * `:line` - The line reported in the __ENV__ variable.

  ## Examples

-      iex> Code.eval_string("a + b", [a: 1, b: 2], file: __ENV__.file, line: __ENV__.line)
-      {3, [a: 1, b: 2]}
+      contents = quote hygiene: false, do: a + b

-      iex> Code.eval_string("c = a + b", [a: 1, b: 2], __ENV__)
-      {3, [a: 1, b: 2, c: 3]}
+      Code.eval_quoted contents, [a: 1, b: 2], file: __ENV__.file, line: __ENV__.line
+      #=> { 3, [ {:a, 1}, {:b, 2} ] }

-      iex> Code.eval_string("a = a + b", [a: 1, b: 2])
-      {3, [a: 3, b: 2]}
+  When passing the __ENV__'s file and line, we could simply get
+  the location which already returns both fields as a keywords lists:

-  For convenience, you can pass `__ENV__/0` as the `opts` argument and
-  all imports, requires and aliases defined in the current environment
-  will be automatically carried over:
-
-      iex> Code.eval_string("a + b", [a: 1, b: 2], __ENV__)
-      {3, [a: 1, b: 2]}
+      Code.eval_quoted contents, [a: 1, b: 2], __ENV__.location
+      #=> { 3, [ {:a, 1}, {:b, 2} ] }

  """
-  def eval_string(string, binding \\ [], opts \\ [])
-
-  def eval_string(string, binding, %Macro.Env{} = env) do
-    {value, binding, _env, _scope} = :elixir.eval to_charlist(string), binding, Map.to_list(env)
-    {value, binding}
-  end
-
-  def eval_string(string, binding, opts) when is_list(opts) do
-    validate_eval_opts(opts)
-    {value, binding, _env, _scope} = :elixir.eval to_charlist(string), binding, opts
-    {value, binding}
+  def eval_quoted(quoted, binding // [], opts // []) do
+    { value, binding, _scope } =
+      Erlang.elixir.eval_quoted [quoted], binding, opts
+    { value, binding }
  end

  @doc """
-  Evaluates the quoted contents.
-
-  **Warning**: Calling this function inside a macro is considered bad
-  practice as it will attempt to evaluate runtime values at compile time.
-  Macro arguments are typically transformed by unquoting them into the
-  returned quoted expressions (instead of evaluated).
-
-  See `eval_string/3` for a description of bindings and options.
-
-  ## Examples
-
-      iex> contents = quote(do: var!(a) + var!(b))
-      iex> Code.eval_quoted(contents, [a: 1, b: 2], file: __ENV__.file, line: __ENV__.line)
-      {3, [a: 1, b: 2]}
-
-  For convenience, you can pass `__ENV__/0` as the `opts` argument and
-  all options will be automatically extracted from the current environment:
-
-      iex> contents = quote(do: var!(a) + var!(b))
-      iex> Code.eval_quoted(contents, [a: 1, b: 2], __ENV__)
-      {3, [a: 1, b: 2]}
-
-  """
-  def eval_quoted(quoted, binding \\ [], opts \\ [])
-
-  def eval_quoted(quoted, binding, %Macro.Env{} = env) do
-    {value, binding, _env, _scope} = :elixir.eval_quoted quoted, binding, Map.to_list(env)
-    {value, binding}
-  end
-
-  def eval_quoted(quoted, binding, opts) when is_list(opts) do
-    validate_eval_opts(opts)
-    {value, binding, _env, _scope} = :elixir.eval_quoted quoted, binding, opts
-    {value, binding}
-  end
-
-  defp validate_eval_opts(opts) do
-    if f = opts[:functions], do: validate_imports(:functions, f)
-    if m = opts[:macros],    do: validate_imports(:macros, m)
-    if a = opts[:aliases],   do: validate_aliases(:aliases, a)
-    if r = opts[:requires],  do: validate_requires(:requires, r)
-  end
-
-  defp validate_requires(kind, requires) do
-    valid = is_list(requires) and Enum.all?(requires, &is_atom(&1))
-
-    unless valid do
-      raise ArgumentError, "expected :#{kind} option given to eval in the format: [module]"
-    end
-  end
-
-  defp validate_aliases(kind, aliases) do
-    valid = is_list(aliases) and Enum.all?(aliases, fn {k, v} ->
-      is_atom(k) and is_atom(v)
-    end)
-
-    unless valid do
-      raise ArgumentError, "expected :#{kind} option given to eval in the format: [{module, module}]"
-    end
-  end
-
-  defp validate_imports(kind, imports) do
-    valid = is_list(imports) and Enum.all?(imports, fn {k, v} ->
-      is_atom(k) and is_list(v) and Enum.all?(v, fn {name, arity} ->
-        is_atom(name) and is_integer(arity)
-      end)
-    end)
-
-    unless valid do
-      raise ArgumentError, "expected :#{kind} option given to eval in the format: [{module, [{name, arity}]}]"
-    end
-  end
-
-  @doc """
-  Converts the given string to its quoted form.
-
-  Returns `{:ok, quoted_form}`
-  if it succeeds, `{:error, {line, error, token}}` otherwise.
+  Converts the given string to AST. It returns { :ok, ast }
+  if it succeeds, { :error, { line, error, token } } otherwise.

  ## Options

-    * `:file` - the filename to be used in stacktraces
-      and the file reported in the `__ENV__/0` macro
+  * `:file` - The filename to be used in stacktraces
+    and the file reported in the __ENV__ variable.

-    * `:line` - the line reported in the `__ENV__/0` macro
+  * `:line` - The line reported in the __ENV__ variable.

-    * `:existing_atoms_only` - when `true`, raises an error
-      when non-existing atoms are found by the tokenizer
-
-  ## Macro.to_string/2
-
-  The opposite of converting a string to its quoted form is
-  `Macro.to_string/2`, which converts a quoted form to a string/binary
-  representation.
  """
-  def string_to_quoted(string, opts \\ []) when is_list(opts) do
+  def string_to_ast(string, opts // []) do
    file = Keyword.get opts, :file, "nofile"
    line = Keyword.get opts, :line, 1
-    :elixir.string_to_quoted(to_charlist(string), line, file, opts)
+    res  = :elixir_translator.raw_forms(:unicode.characters_to_list(string), line, file)
+    case res do
+      { :ok, ast } -> { :ok, unpack_ast(line, ast) }
+      _ -> res
+    end
  end

  @doc """
-  Converts the given string to its quoted form.
-
-  It returns the ast if it succeeds,
-  raises an exception otherwise. The exception is a `TokenMissingError`
+  Converts the given string to AST. It returns the ast if it succeeds,
+  raises an exception otherwise. The exception is a TokenMissingError
  in case a token is missing (usually because the expression is incomplete),
-  `SyntaxError` otherwise.
+  SyntaxError otherwise.
+
+  ## Options
+
+  * `:file` - The filename to be used in stacktraces
+    and the file reported in the __ENV__ variable.
+
+  * `:line` - The line reported in the __ENV__ variable.

-  Check `string_to_quoted/2` for options information.
  """
-  def string_to_quoted!(string, opts \\ []) when is_list(opts) do
+  def string_to_ast!(string, opts // []) do
    file = Keyword.get opts, :file, "nofile"
    line = Keyword.get opts, :line, 1
-    :elixir.string_to_quoted!(to_charlist(string), line, file, opts)
+    res  = :elixir_translator.forms(:unicode.characters_to_list(string), line, file)
+    unpack_ast(line, res)
+  end
+
+  defp unpack_ast(_line, []),                              do: nil
+  defp unpack_ast(_line, [forms]) when not is_list(forms), do: forms
+  defp unpack_ast(line, forms),                            do: { :__block__, line, forms }
+
+  @doc """
+  Loads the given `file`. Accepts `relative_to` as an argument to tell
+  where the file is located. If the file was already required/loaded,
+  loads it again. It returns the full path of the loaded file.
+
+  When loading a file, you may skip passing .exs as extension as Elixir
+  automatically adds it for you.
+  """
+  def load_file(file, relative_to // nil) when is_binary(file) do
+    file = find_file(file, relative_to)
+    server_call { :loaded, file }
+    Erlang.elixir_compiler.file file
+    file
  end

  @doc """
-  Evals the given file.
+  Requires the given `file`. Accepts `relative_to` as an argument to tell
+  where the file is located. If the file was already required/loaded,
+  returns nil, otherwise the full path of the loaded file.

-  Accepts `relative_to` as an argument to tell where the file is located.
-
-  While `load_file` loads a file and returns the loaded modules and their
-  byte code, `eval_file` simply evaluates the file contents and returns the
-  evaluation result and its bindings.
+  When requiring a file, you may skip passing .exs as extension as
+  Elixir automatically adds it for you.
  """
-  def eval_file(file, relative_to \\ nil) do
-    file = find_file(file, relative_to)
-    eval_string File.read!(file), [], [file: file, line: 1]
-  end
-
-  @doc """
-  Loads the given file.
-
-  Accepts `relative_to` as an argument to tell where the file is located.
-  If the file was already required/loaded, loads it again.
-
-  It returns a list of tuples `{ModuleName, <<byte_code>>}`, one tuple for
-  each module defined in the file.
-
-  Notice that if `load_file` is invoked by different processes concurrently,
-  the target file will be loaded concurrently many times. Check `require_file/2`
-  if you don't want a file to be loaded concurrently.
-
-  ## Examples
-
-      Code.load_file("eex_test.exs", "../eex/test") |> List.first
-      #=> {EExTest.Compiled, <<70, 79, 82, 49, ...>>}
-
-  """
-  def load_file(file, relative_to \\ nil) when is_binary(file) do
-    file = find_file(file, relative_to)
-    :elixir_code_server.call {:acquire, file}
-    loaded = :elixir_compiler.file file
-    :elixir_code_server.cast {:loaded, file}
-    loaded
-  end
-
-  @doc """
-  Requires the given `file`.
-
-  Accepts `relative_to` as an argument to tell where the file is located.
-  The return value is the same as that of `load_file/2`. If the file was already
-  required/loaded, doesn't do anything and returns `nil`.
-
-  Notice that if `require_file` is invoked by different processes concurrently,
-  the first process to invoke `require_file` acquires a lock and the remaining
-  ones will block until the file is available. I.e. if `require_file` is called
-  N times with a given file, it will be loaded only once. The first process to
-  call `require_file` will get the list of loaded modules, others will get `nil`.
-
-  Check `load_file/2` if you want a file to be loaded multiple times. See also
-  `unload_files/1`
-
-  ## Examples
-
-  If the code is already loaded, it returns `nil`:
-
-      Code.require_file("eex_test.exs", "../eex/test") #=> nil
-
-  If the code is not loaded yet, it returns the same as `load_file/2`:
-
-      Code.require_file("eex_test.exs", "../eex/test") |> List.first
-      #=> {EExTest.Compiled, <<70, 79, 82, 49, ...>>}
-
-  """
-  def require_file(file, relative_to \\ nil) when is_binary(file) do
+  def require_file(file, relative_to // nil) when is_binary(file) do
    file = find_file(file, relative_to)

-    case :elixir_code_server.call({:acquire, file}) do
-      :loaded  ->
-        nil
-      {:queued, ref}  ->
-        receive do {:elixir_code_server, ^ref, :loaded} -> nil end
-      :proceed ->
-        loaded = :elixir_compiler.file file
-        :elixir_code_server.cast {:loaded, file}
-        loaded
+    case server_call({ :loaded, file }) do
+      :ok         -> Erlang.elixir_compiler.file file
+      :duplicated -> []
    end
  end

  @doc """
-  Gets the compilation options from the code server.
-
-  Check `compiler_options/1` for more information.
-
-  ## Examples
-
-      Code.compiler_options
-      #=> %{debug_info: true, docs: true,
-            warnings_as_errors: false, ignore_module_conflict: false}
-
+  Loads the compilation options from the code server.
+  Check compiler_options/1 for more information.
  """
  def compiler_options do
-    :elixir_config.get :compiler_options
+    server_call :compiler_options
  end

  @doc """
-  Returns a list with the available compiler options.
-
-  See `Code.compiler_options/1` for more info.
-
-  ## Examples
-
-      iex> Code.available_compiler_options
-      [:docs, :debug_info, :ignore_module_conflict, :relative_paths, :warnings_as_errors]
-
-  """
-  def available_compiler_options do
-    [:docs, :debug_info, :ignore_module_conflict, :relative_paths, :warnings_as_errors]
-  end
-
-  @doc """
-  Sets compilation options.
-
-  These options are global since they are stored by Elixir's Code Server.
+  Sets compilation options. Those options are global
+  since they are stored by Elixir's Code Server.

  Available options are:

-    * `:docs` - when `true`, retain documentation in the compiled module,
-      `true` by default
-
-    * `:debug_info` - when `true`, retain debug information in the compiled
-      module; this allows a developer to reconstruct the original source
-      code, `false` by default
-
-    * `:ignore_module_conflict` - when `true`, override modules that were
-      already defined without raising errors, `false` by default
-
-    * `:relative_paths` - when `true`, use relative paths in quoted nodes,
-      warnings and errors generated by the compiler, `true` by default.
-      Note disabling this option won't affect runtime warnings and errors.
-
-    * `:warnings_as_errors` - causes compilation to fail when warnings are
-      generated
-
-  It returns the new list of compiler options.
-
-  ## Examples
-
-      Code.compiler_options(debug_info: true)
-      #=> %{debug_info: true, docs: true,
-            warnings_as_errors: false, ignore_module_conflict: false}
+  * docs       - when true, retain documentation in the compiled module.
+                 True by default;
+  * debug_info - when true, retain debug information in the compiled module.
+                 This allows a developer to reconstruct the original source
+                 code, for such reasons, false by default;
+  * ignore_module_conflict - when true, override modules that were already defined
+                             without raising errors, false by default;

  """
  def compiler_options(opts) do
-    available = available_compiler_options()
-
-    Enum.each(opts, fn({key, value}) ->
-      cond do
-        not key in available ->
-          raise "unknown compiler option: #{inspect(key)}"
-        not is_boolean(value) ->
-          raise "compiler option #{inspect(key)} should be a boolean, got: #{inspect(value)}"
-        true ->
-          :ok
-      end
-    end)
-
-    :elixir_config.update :compiler_options, &Enum.into(opts, &1)
+    server_call { :compiler_options, opts }
  end

  @doc """
-  Compiles the given string.
+  Compiles the given string and returns a list of tuples where
+  the first element is the module name and the second one is its
+  binary.

-  Returns a list of tuples where the first element is the module name
-  and the second one is its byte code (as a binary).
-
-  For compiling many files at once, check `Kernel.ParallelCompiler.files/2`.
+  For compiling many files at once, check `Kernel.ParallelCompiler`.
  """
-  def compile_string(string, file \\ "nofile") when is_binary(file) do
-    :elixir_compiler.string to_charlist(string), file
+  def compile_string(string, file // "nofile") when is_binary(file) do
+    Erlang.elixir_compiler.string :unicode.characters_to_list(string), to_binary(file)
  end

  @doc """
-  Compiles the quoted expression.
+  Ensures the given module is loaded. If the module is already
+  loaded, it works as no-op. If the module was not loaded yet,
+  it tries to load it.

-  Returns a list of tuples where the first element is the module name and
-  the second one is its byte code (as a binary).
-  """
-  def compile_quoted(quoted, file \\ "nofile") when is_binary(file) do
-    :elixir_compiler.quoted quoted, file
-  end
-
-  @doc """
-  Ensures the given module is loaded.
-
-  If the module is already loaded, this works as no-op. If the module
-  was not yet loaded, it tries to load it.
-
-  If it succeeds loading the module, it returns `{:module, module}`.
-  If not, returns `{:error, reason}` with the error reason.
+  If it succeeds loading the module anyhow, it returns
+  `{ :module, module }`. If not, returns `{ :error, reason }` with
+  the error reason.

  ## Code loading on the Erlang VM

  Erlang has two modes to load code: interactive and embedded.

-  By default, the Erlang VM runs in interactive mode, where modules
+  By default, the Erlang VM runs on interactive mode, where modules
  are loaded as needed. In embedded mode the opposite happens, as all
  modules need to be loaded upfront or explicitly.

-  Therefore, this function is used to check if a module is loaded
-  before using it and allows one to react accordingly. For example, the `URI`
-  module uses this function to check if a specific parser exists for a given
-  URI scheme.
+  Therefore, this function is useful to check if a module is loaded
+  before using it and react accordingly. For example, the `URI` module
+  uses this function to check if a specific parser exists and is for the
+  given URI scheme.

-  ## Code.ensure_compiled/1
+  ## Code.ensure_compiled

  Elixir also contains an `ensure_compiled/1` function that is a
  superset of `ensure_loaded/1`.

  Since Elixir's compilation happens in parallel, in some situations
-  you may need to use a module that was not yet compiled, therefore
+  you may need to use a module but it was not compiled yet, therefore
  it can't even be loaded.

-  `ensure_compiled/1` halts the current process until the
+  `ensure_compiled/1` puts a halt in the current process until the
  module we are depending on is available.

-  In most cases, `ensure_loaded/1` is enough. `ensure_compiled/1`
-  must be used in rare cases, usually involving macros that need to
-  invoke a module for callback information.
-
-  ## Examples
-
-      iex> Code.ensure_loaded(Atom)
-      {:module, Atom}
-
-      iex> Code.ensure_loaded(DoesNotExist)
-      {:error, :nofile}
-
+  In most of the cases, `ensure_loaded` is enough. `ensure_compiled`
+  must be used just in same rare conditions, usually involving macros
+  that needs to invoke a module for callback information.
  """
-  @spec ensure_loaded(module) ::
-        {:module, module} | {:error, :embedded | :badfile | :nofile | :on_load_failure}
  def ensure_loaded(module) when is_atom(module) do
-    :code.ensure_loaded(module)
+    Erlang.code.ensure_loaded(module)
  end

  @doc """
-  Ensures the given module is loaded.
+  Ensures the given module is compiled and loaded. If the module
+  is already loaded, it works as no-op. If the module was not
+  loaded yet, it checks if it needs to be compiled first and just
+  then tries to load it.

-  Similar to `ensure_loaded/1`, but returns `true` if the module
-  is already loaded or was successfully loaded. Returns `false`
-  otherwise.
-
-  ## Examples
-
-      iex> Code.ensure_loaded?(Atom)
-      true
-
-  """
-  def ensure_loaded?(module) when is_atom(module) do
-    match?({:module, ^module}, ensure_loaded(module))
-  end
-
-  @doc """
-  Ensures the given module is compiled and loaded.
-
-  If the module is already loaded, it works as no-op. If the module was
-  not loaded yet, it checks if it needs to be compiled first and then
-  tries to load it.
-
-  If it succeeds loading the module, it returns `{:module, module}`.
-  If not, returns `{:error, reason}` with the error reason.
+  If it succeeds loading the module anyhow, it returns
+  `{ :module, module }`. If not, returns `{ :error, reason }` with
+  the error reason.

  Check `ensure_loaded/1` for more information on module loading
  and when to use `ensure_loaded/1` or `ensure_compiled/1`.
  """
-  @spec ensure_compiled(module) ::
-        {:module, module} | {:error, :embedded | :badfile | :nofile | :on_load_failure}
  def ensure_compiled(module) when is_atom(module) do
-    case :code.ensure_loaded(module) do
-      {:error, :nofile} = error ->
-        if is_pid(:erlang.get(:elixir_compiler_pid)) and
-           Kernel.ErrorHandler.ensure_compiled(module, :module) do
-          {:module, module}
-        else
-          error
+    case Erlang.code.ensure_loaded(module) do
+      { :error, :nofile } = error ->
+        case :erlang.get(:elixir_compiler_pid) do
+          :undefined -> error
+          _ ->
+            try do
+              module.__info__(:self)
+              { :module, module }
+            rescue
+              UndefinedFunctionError -> error
+            end
        end
      other -> other
    end
  end

-  @doc """
-  Ensures the given module is compiled and loaded.
-
-  Similar to `ensure_compiled/1`, but returns `true` if the module
-  is already loaded or was successfully loaded and compiled.
-  Returns `false` otherwise.
-  """
-  @spec ensure_compiled?(module) :: boolean
-  def ensure_compiled?(module) when is_atom(module) do
-    match?({:module, ^module}, ensure_compiled(module))
-  end
-
-  @doc ~S"""
-  Returns the docs for the given module.
-
-  When given a module name, it finds its BEAM code and reads the docs from it.
-
-  When given a path to a .beam file, it will load the docs directly from that
-  file.
-
-  The return value depends on the `kind` value:
-
-    * `:docs` - list of all docstrings attached to functions and macros
-      using the `@doc` attribute
-
-    * `:moduledoc` - tuple `{<line>, <doc>}` where `line` is the line on
-      which module definition starts and `doc` is the string
-      attached to the module using the `@moduledoc` attribute
-
-    * `:callback_docs` - list of all docstrings attached to
-      `@callbacks` using the `@doc` attribute
-
-    * `:type_docs` - list of all docstrings attached to
-      `@type` callbacks using the `@typedoc` attribute
-
-    * `:all` - a keyword list with `:docs` and `:moduledoc`, `:callback_docs`,
-      and `:type_docs`.
-
-  If the module cannot be found, it returns `nil`.
-
-  ## Examples
-
-      # Get the module documentation
-      iex> {_line, text} = Code.get_docs(Atom, :moduledoc)
-      iex> String.split(text, "\n") |> Enum.at(0)
-      "Convenience functions for working with atoms."
-
-      # Module doesn't exist
-      iex> Code.get_docs(ModuleNotGood, :all)
-      nil
-
-  """
-  @doc_kinds [:docs, :moduledoc, :callback_docs, :type_docs, :all]
-
-  def get_docs(module, kind) when is_atom(module) and kind in @doc_kinds do
-    case :code.get_object_code(module) do
-      {_module, bin, _beam_path} ->
-        do_get_docs(bin, kind)
-
-      :error -> nil
-    end
-  end
-
-  def get_docs(binpath, kind) when is_binary(binpath) and kind in @doc_kinds do
-    do_get_docs(String.to_charlist(binpath), kind)
-  end
-
-  @docs_chunk 'ExDc'
-
-  defp do_get_docs(bin_or_path, kind) do
-    case :beam_lib.chunks(bin_or_path, [@docs_chunk]) do
-      {:ok, {_module, [{@docs_chunk, bin}]}} ->
-        lookup_docs(:erlang.binary_to_term(bin), kind)
-
-      {:error, :beam_lib, {:missing_chunk, _, @docs_chunk}} -> nil
-    end
-  end
-
-  defp lookup_docs({:elixir_docs_v1, docs}, kind),
-    do: do_lookup_docs(docs, kind)
-
-  # unsupported chunk version
-  defp lookup_docs(_, _), do: nil
-
-  defp do_lookup_docs(docs, :all), do: docs
-  defp do_lookup_docs(docs, kind),
-    do: Keyword.get(docs, kind)
-
  ## Helpers

  # Finds the file given the relative_to path.
-  #
  # If the file is found, returns its path in binary, fails otherwise.
  defp find_file(file, relative_to) do
+    file = to_binary(file)
+
    file = if relative_to do
-      Path.expand(file, relative_to)
+      File.expand_path(file, relative_to)
    else
-      Path.expand(file)
+      File.expand_path(file)
    end

    if File.regular?(file) do
      file
    else
-      raise Code.LoadError, file: file
+      prefix = "#{file}.exs"
+      if File.regular?(prefix) do
+        prefix
+      else
+        raise ArgumentError, message: "could not load #{file}"
+      end
    end
  end
+
+  defp server_call(args) do
+    Erlang.gen_server.call(:elixir_code_server, args)
+  end
 end
@@ -1,77 +0,0 @@
-defprotocol Collectable do
-  @moduledoc """
-  A protocol to traverse data structures.
-
-  The `Enum.into/2` function uses this protocol to insert an
-  enumerable into a collection:
-
-      iex> Enum.into([a: 1, b: 2], %{})
-      %{a: 1, b: 2}
-
-  ## Why Collectable?
-
-  The `Enumerable` protocol is useful to take values out of a collection.
-  In order to support a wide range of values, the functions provided by
-  the `Enumerable` protocol do not keep shape. For example, passing a
-  map to `Enum.map/2` always returns a list.
-
-  This design is intentional. `Enumerable` was designed to support infinite
-  collections, resources and other structures with fixed shape. For example,
-  it doesn't make sense to insert values into a range, as it has a fixed
-  shape where just the range limits are stored.
-
-  The `Collectable` module was designed to fill the gap left by the
-  `Enumerable` protocol. `into/1` can be seen as the opposite of
-  `Enumerable.reduce/3`. If `Enumerable` is about taking values out,
-  `Collectable.into/1` is about collecting those values into a structure.
-  """
-
-  @type command :: {:cont, term} | :done | :halt
-
-  @doc """
-  Returns a function that collects values alongside
-  the initial accumulation value.
-
-  The returned function receives a collectable and injects a given
-  value into it for every `{:cont, term}` instruction.
-
-  `:done` is passed when no further values will be injected, useful
-  for closing resources and normalizing values. A collectable must
-  be returned on `:done`.
-
-  If injection is suddenly interrupted, `:halt` is passed and it can
-  return any value, as it won't be used.
-  """
-  @spec into(t) :: {term, (term, command -> t | term)}
-  def into(collectable)
-end
-
-defimpl Collectable, for: List do
-  def into(original) do
-    {[], fn
-      list, {:cont, x} -> [x | list]
-      list, :done -> original ++ :lists.reverse(list)
-      _, :halt -> :ok
-    end}
-  end
-end
-
-defimpl Collectable, for: BitString do
-  def into(original) do
-    {original, fn
-      acc, {:cont, x} when is_bitstring(x) -> [acc | x]
-      acc, :done -> IO.iodata_to_binary(acc)
-      _, :halt -> :ok
-    end}
-  end
-end
-
-defimpl Collectable, for: Map do
-  def into(original) do
-    {original, fn
-      map, {:cont, {k, v}} -> :maps.put(k, v, map)
-      map, :done -> map
-      _, :halt -> :ok
-    end}
-  end
-end
@@ -1,368 +1,152 @@
-defmodule Dict do
-  @moduledoc ~S"""
-  WARNING: this module is deprecated.
+defprotocol Dict do
+  @only [Record]

-  If you need a general dictionary, use the `Map` module.
-  If you need to manipulate keyword lists, use `Keyword`.
-
-  To convert maps into keywords and vice-versa, use the
-  `new` function in the respective modules.
+  @moduledoc """
+  This module provides the Dict protocol
+  with the goal of being a common API
+  to work with dictionaries.
  """

-  @type key :: any
-  @type value :: any
-  @type t :: list | map
+  @doc """
+  Returns a list containing all dict's keys.
+  The keys are not guaranteed to be sorted, unless
+  the underlying dict implementation defines so.

-  # TODO: Deprecate every function by 1.4
-  defmacro __using__(_) do
-    # Use this import to guarantee proper code expansion
-    import Kernel, except: [size: 1]
+  ## Examples

-    %{file: file, line: line} = __CALLER__
-    :elixir_errors.warn(line, file, "the Dict module is deprecated")
+      Dict.keys [a: 1, b: 2]  #=> [:a,:b]

-    quote do
-      def get(dict, key, default \\ nil) do
-        case fetch(dict, key) do
-          {:ok, value} -> value
-          :error -> default
-        end
+  """
+  def keys(dict)
+
+  @doc """
+  Returns a list containing all dict's values.
+
+  ## Examples
+
+      Dict.values [a: 1, b: 2]  #=> [1,2]
+
+  """
+  def values(dict)
+
+  @doc """
+  Returns the number of elements in `dict`.
+
+  ## Examples
+
+      Dict.size [a: 1, b: 2]  #=> 2
+
+  """
+  def size(dict)
+
+  @doc """
+  Returns whether the given key exists in the given dict.
+
+  ## Examples
+
+      Dict.has_key?([a: 1], :a)  #=> true
+      Dict.has_key?([a: 1], :b)  #=> false
+
+  """
+  def has_key?(dict, key)
+
+  @doc """
+  Returns the value associated with `key` in `dict`. If `dict` does not
+  contain `key`, returns `default` (or nil if not provided).
+
+  ## Examples
+
+      Dict.get [a: 1], :a     #=> 1
+      Dict.get [a: 1], :b     #=> nil
+      Dict.get [a: 1], :b, 3  #=> 3
+
+  """
+  def get(dict, key)
+  def get(dict, key, default)
+
+  @doc """
+  Stores the given `value` under `key` in `dict`.
+  If `dict` already has `key`, the stored value is replaced by the new one.
+
+  ## Examples
+
+      Dict.put [a: 1, b: 2], :a, 3
+      #=> [a: 3, b: 2]
+
+  """
+  def put(dict, key, val)
+
+  @doc """
+  Removes the entry stored under the given key from `dict`.
+  If `dict` does not contain `key`, returns the dictionary unchanged.
+
+  ## Examples
+
+      Dict.delete [a: 1, b: 2], :a  #=> [b: 2]
+      Dict.delete [b: 2], :a        #=> [b: 2]
+
+  """
+  def delete(dict, key)
+
+  @doc """
+  Merges two dicts into one. If the dicts have duplicated entries, the one
+  given as second argument wins.
+
+  ## Examples
+
+      Dict.merge [a: 1, b: 2], [a: 3, d: 4]
+      #=> [a:3, b:2, d: 4]
+
+  """
+  def merge(dict1, dict2)
+
+  @doc """
+  Merges two dicts into one. If the dicts have duplicated entries, the given
+  function is invoked to solve conflicts.
+
+  ## Examples
+
+      Dict.merge [a: 1, b: 2], [a: 3, d: 4], fn _k, v1, v2 ->
+        v1 + v2
      end
+      #=> [a: 4, b: 2, d: 4]

-      def get_lazy(dict, key, fun) when is_function(fun, 0) do
-        case fetch(dict, key) do
-          {:ok, value} -> value
-          :error -> fun.()
-        end
-      end
+  """
+  def merge(dict1, dict2, fun)

-      def get_and_update(dict, key, fun) do
-        current_value = get(dict, key)
-        {get, new_value} = fun.(current_value)
-        {get, put(dict, key, new_value)}
-      end
+  @doc """
+  Update a value in `dict` by calling `fun` on the value to get a new
+  value. An exception is generated if `key` is not present in the dict.

-      def fetch!(dict, key) do
-        case fetch(dict, key) do
-          {:ok, value} -> value
-          :error -> raise KeyError, key: key, term: dict
-        end
-      end
+  ## Examples

-      def has_key?(dict, key) do
-        match? {:ok, _}, fetch(dict, key)
-      end
+      Dict.update [a: 1, b: 2], :a, fn val -> -val end
+      #=> [a: -1, b: 2]

-      def put_new(dict, key, value) do
-        case has_key?(dict, key) do
-          true  -> dict
-          false -> put(dict, key, value)
-        end
-      end
+  """
+  def update(dict, key, fun)

-      def put_new_lazy(dict, key, fun) when is_function(fun, 0) do
-        case has_key?(dict, key) do
-          true  -> dict
-          false -> put(dict, key, fun.())
-        end
-      end
+  @doc """
+  Update a value in `dict` by calling `fun` on the value to get a new value. If
+  `key` is not present in `dict` then `initial` will be stored as the first
+  value.

-      def drop(dict, keys) do
-        Enum.reduce(keys, dict, &delete(&2, &1))
-      end
+  ## Examples

-      def take(dict, keys) do
-        Enum.reduce(keys, new(), fn key, acc ->
-          case fetch(dict, key) do
-            {:ok, value} -> put(acc, key, value)
-            :error -> acc
-          end
-        end)
-      end
+      Dict.update [a: 1, b: 2], :c, 3, fn val -> -val end
+      #=> [a: 1, b: 2, c: 3]

-      def to_list(dict) do
-        reduce(dict, {:cont, []}, fn
-          kv, acc -> {:cont, [kv | acc]}
-        end) |> elem(1) |> :lists.reverse
-      end
+  """
+  def update(dict, key, initial, fun)

-      def keys(dict) do
-        reduce(dict, {:cont, []}, fn
-          {k, _}, acc -> {:cont, [k | acc]}
-        end) |> elem(1) |> :lists.reverse
-      end
+  @doc """
+  Returns an empty dict of the same type as `dict`.
+  """
+  def empty(dict)

-      def values(dict) do
-        reduce(dict, {:cont, []}, fn
-          {_, v}, acc -> {:cont, [v | acc]}
-        end) |> elem(1) |> :lists.reverse
-      end
-
-      def equal?(dict1, dict2) do
-        # Use this import to avoid conflicts in the user code
-        import Kernel, except: [size: 1]
-
-        case size(dict1) == size(dict2) do
-          false -> false
-          true  ->
-            reduce(dict1, {:cont, true}, fn({k, v}, _acc) ->
-              case fetch(dict2, k) do
-                {:ok, ^v} -> {:cont, true}
-                _ -> {:halt, false}
-              end
-            end) |> elem(1)
-        end
-      end
-
-      def merge(dict1, dict2, fun \\ fn(_k, _v1, v2) -> v2 end) do
-        # Use this import to avoid conflicts in the user code
-        import Kernel, except: [size: 1]
-
-        if size(dict1) < size(dict2) do
-          reduce(dict1, {:cont, dict2}, fn {k, v1}, acc ->
-            {:cont, update(acc, k, v1, &fun.(k, v1, &1))}
-          end)
-        else
-          reduce(dict2, {:cont, dict1}, fn {k, v2}, acc ->
-            {:cont, update(acc, k, v2, &fun.(k, &1, v2))}
-          end)
-        end |> elem(1)
-      end
-
-      def update(dict, key, initial, fun) do
-        case fetch(dict, key) do
-          {:ok, value} ->
-            put(dict, key, fun.(value))
-          :error ->
-            put(dict, key, initial)
-        end
-      end
-
-      def update!(dict, key, fun) do
-        case fetch(dict, key) do
-          {:ok, value} ->
-            put(dict, key, fun.(value))
-          :error ->
-            raise KeyError, key: key, term: dict
-        end
-      end
-
-      def pop(dict, key, default \\ nil) do
-        case fetch(dict, key) do
-          {:ok, value} ->
-            {value, delete(dict, key)}
-          :error ->
-            {default, dict}
-        end
-      end
-
-      def pop_lazy(dict, key, fun) when is_function(fun, 0) do
-        case fetch(dict, key) do
-          {:ok, value} ->
-            {value, delete(dict, key)}
-          :error ->
-            {fun.(), dict}
-        end
-      end
-
-      def split(dict, keys) do
-        Enum.reduce(keys, {new(), dict}, fn key, {inc, exc} = acc ->
-          case fetch(exc, key) do
-            {:ok, value} ->
-              {put(inc, key, value), delete(exc, key)}
-            :error ->
-              acc
-          end
-        end)
-      end
-
-      defoverridable merge: 2, merge: 3, equal?: 2, to_list: 1, keys: 1,
-                     values: 1, take: 2, drop: 2, get: 2, get: 3, fetch!: 2,
-                     has_key?: 2, put_new: 3, pop: 2, pop: 3, split: 2,
-                     update: 4, update!: 3, get_and_update: 3, get_lazy: 3,
-                     pop_lazy: 3, put_new_lazy: 3
-    end
-  end
-
-  defmacrop target(dict) do
-    quote do
-      case unquote(dict) do
-        %{__struct__: x} when is_atom(x) ->
-          x
-        %{} ->
-          Map
-        x when is_list(x) ->
-          Keyword
-        x ->
-          unsupported_dict(x)
-      end
-    end
-  end
-
-  @spec keys(t) :: [key]
-  def keys(dict) do
-    target(dict).keys(dict)
-  end
-
-  @spec values(t) :: [value]
-  def values(dict) do
-    target(dict).values(dict)
-  end
-
-  @spec size(t) :: non_neg_integer
-  def size(dict) do
-    target(dict).size(dict)
-  end
-
-  @spec has_key?(t, key) :: boolean
-  def has_key?(dict, key) do
-    target(dict).has_key?(dict, key)
-  end
-
-  @spec get(t, key, value) :: value
-  def get(dict, key, default \\ nil) do
-    target(dict).get(dict, key, default)
-  end
-
-  @spec get_lazy(t, key, (() -> value)) :: value
-  def get_lazy(dict, key, fun) do
-    target(dict).get_lazy(dict, key, fun)
-  end
-
-  @spec get_and_update(t, key, (value -> {value, value})) :: {value, t}
-  def get_and_update(dict, key, fun) do
-    target(dict).get_and_update(dict, key, fun)
-  end
-
-  @spec fetch(t, key) :: value
-  def fetch(dict, key) do
-    target(dict).fetch(dict, key)
-  end
-
-  @spec fetch!(t, key) :: value | no_return
-  def fetch!(dict, key) do
-    target(dict).fetch!(dict, key)
-  end
-
-  @spec put(t, key, value) :: t
-  def put(dict, key, val) do
-    target(dict).put(dict, key, val)
-  end
-
-  @spec put_new(t, key, value) :: t
-  def put_new(dict, key, val) do
-    target(dict).put_new(dict, key, val)
-  end
-
-  @spec put_new_lazy(t, key, (() -> value)) :: t
-  def put_new_lazy(dict, key, fun) do
-    target(dict).put_new_lazy(dict, key, fun)
-  end
-
-  @spec delete(t, key) :: t
-  def delete(dict, key) do
-    target(dict).delete(dict, key)
-  end
-
-  @spec merge(t, t) :: t
-  def merge(dict1, dict2) do
-    target1 = target(dict1)
-    target2 = target(dict2)
-
-    if target1 == target2 do
-      target1.merge(dict1, dict2)
-    else
-      do_merge(target1, dict1, dict2, fn(_k, _v1, v2) -> v2 end)
-    end
-  end
-
-  @spec merge(t, t, (key, value, value -> value)) :: t
-  def merge(dict1, dict2, fun) do
-    target1 = target(dict1)
-    target2 = target(dict2)
-
-    if target1 == target2 do
-      target1.merge(dict1, dict2, fun)
-    else
-      do_merge(target1, dict1, dict2, fun)
-    end
-  end
-
-  defp do_merge(target1, dict1, dict2, fun) do
-    Enumerable.reduce(dict2, {:cont, dict1}, fn({k, v}, acc) ->
-      {:cont, target1.update(acc, k, v, fn(other) -> fun.(k, other, v) end)}
-    end) |> elem(1)
-  end
-
-  @spec pop(t, key, value) :: {value, t}
-  def pop(dict, key, default \\ nil) do
-    target(dict).pop(dict, key, default)
-  end
-
-  @spec pop_lazy(t, key, (() -> value)) :: {value, t}
-  def pop_lazy(dict, key, fun) do
-    target(dict).pop_lazy(dict, key, fun)
-  end
-
-  @spec update!(t, key, (value -> value)) :: t
-  def update!(dict, key, fun) do
-    target(dict).update!(dict, key, fun)
-  end
-
-  @spec update(t, key, value, (value -> value)) :: t
-  def update(dict, key, initial, fun) do
-    target(dict).update(dict, key, initial, fun)
-  end
-
-  @spec split(t, [key]) :: {t, t}
-  def split(dict, keys) do
-    target(dict).split(dict, keys)
-  end
-
-  @spec drop(t, [key]) :: t
-  def drop(dict, keys) do
-    target(dict).drop(dict, keys)
-  end
-
-  @spec take(t, [key]) :: t
-  def take(dict, keys) do
-    target(dict).take(dict, keys)
-  end
-
-  @spec empty(t) :: t
-  def empty(dict) do
-    target(dict).empty(dict)
-  end
-
-  @spec equal?(t, t) :: boolean
-  def equal?(dict1, dict2) do
-    target1 = target(dict1)
-    target2 = target(dict2)
-
-    cond do
-      target1 == target2 ->
-        target1.equal?(dict1, dict2)
-
-      target1.size(dict1) == target2.size(dict2) ->
-        Enumerable.reduce(dict2, {:cont, true}, fn({k, v}, _acc) ->
-          case target1.fetch(dict1, k) do
-            {:ok, ^v} -> {:cont, true}
-            _         -> {:halt, false}
-          end
-        end) |> elem(1)
-
-      true ->
-        false
-    end
-  end
-
-  @spec to_list(t) :: list
-  def to_list(dict) do
-    target(dict).to_list(dict)
-  end
-
-  @spec unsupported_dict(t) :: no_return
-  defp unsupported_dict(dict) do
-    raise ArgumentError, "unsupported dict: #{inspect dict}"
-  end
-end
+  @doc """
+  Returns a list of key-value pairs stored in `dict`.
+  No particular order is enforced.
+  """
+  def to_list(dict)
+end
@@ -0,0 +1,45 @@
+defmodule Dict.Common do
+  @moduledoc false
+
+  defmacro __using__(ref) do
+    quote do
+      @doc """
+      Creates a new empty dict.
+      """
+      def new do
+        unquote(ref).empty(nil)
+      end
+
+      @doc """
+      Creates a new dict from a list of pairs.
+
+      ## Examples
+
+          #{inspect(__MODULE__)}.new [{:b,1},{:a,2}]
+          #=> [a: 1, b: 2]
+
+      """
+      def new(pairs) do
+        Enum.reduce pairs, new, fn { k, v }, dict ->
+          unquote(ref).put(dict, k, v)
+        end
+      end
+
+      @doc """
+      Creates a new dict from a list of elements with the
+      help of the transformation function.
+
+      ## Examples
+
+          #{inspect(__MODULE__)}.new ["a", "b"], fn x -> {x, x} end
+          #=> ["a": "a", "b": "b"]
+      """
+      def new(list, transform) when is_function(transform) do
+        Enum.reduce list, new(), fn i, dict ->
+          { k, v } = transform.(i)
+          unquote(ref).put(dict, k, v)
+        end
+      end
+    end
+  end
+end
@@ -1,77 +0,0 @@
-require Record
-
-defmodule File.Stat do
-  @moduledoc """
-  A struct that holds file information.
-
-  In Erlang, this struct is represented by a `:file_info` record.
-  Therefore this module also provides functions for converting
-  between the Erlang record and the Elixir struct.
-
-  Its fields are:
-
-    * `size` - size of file in bytes.
-
-    * `type` - `:device | :directory | :regular | :other`; the type of the
-      file.
-
-    * `access` - `:read | :write | :read_write | :none`; the current system
-      access to the file.
-
-    * `atime` - the last time the file was read.
-
-    * `mtime` - the last time the file was written.
-
-    * `ctime` - the interpretation of this time field depends on the operating
-      system. On Unix, it is the last time the file or the inode was changed.
-      In Windows, it is the time of creation.
-
-    * `mode` - the file permissions.
-
-    * `links` - the number of links to this file. This is always 1 for file
-      systems which have no concept of links.
-
-    * `major_device` - identifies the file system where the file is located.
-      In Windows, the number indicates a drive as follows: 0 means A:, 1 means
-      B:, and so on.
-
-    * `minor_device` - only valid for character devices on Unix. In all other
-      cases, this field is zero.
-
-    * `inode` - gives the inode number. On non-Unix file systems, this field
-      will be zero.
-
-    * `uid` - indicates the owner of the file. Will be zero for non-Unix file
-      systems.
-
-    * `gid` - indicates the group that owns the file. Will be zero for
-      non-Unix file systems.
-
-  The time type returned in `atime`, `mtime`, and `ctime` is dependent on the
-  time type set in options. `{:time, type}` where type can be `:local`,
-  `:universal`, or `:posix`. Default is `:universal`.
-  """
-
-  record = Record.extract(:file_info, from_lib: "kernel/include/file.hrl")
-  keys   = :lists.map(&elem(&1, 0), record)
-  vals   = :lists.map(&{&1, [], nil}, keys)
-  pairs  = :lists.zip(keys, vals)
-
-  defstruct keys
-  @type t :: %__MODULE__{}
-
-  @doc """
-  Converts a `File.Stat` struct to a `:file_info` record.
-  """
-  def to_record(%File.Stat{unquote_splicing(pairs)}) do
-    {:file_info, unquote_splicing(vals)}
-  end
-
-  @doc """
-  Converts a `:file_info` record into a `File.Stat`.
-  """
-  def from_record(file_info)
-  def from_record({:file_info, unquote_splicing(vals)}) do
-    %File.Stat{unquote_splicing(pairs)}
-  end
-end
@@ -1,99 +0,0 @@
-defmodule File.Stream do
-  @moduledoc """
-  Defines a `File.Stream` struct returned by `File.stream!/3`.
-
-  The following fields are public:
-
-    * `path`          - the file path
-    * `modes`         - the file modes
-    * `raw`           - a boolean indicating if bin functions should be used
-    * `line_or_bytes` - if reading should read lines or a given amount of bytes
-
-  """
-
-  defstruct path: nil, modes: [], line_or_bytes: :line, raw: true
-
-  @type t :: %__MODULE__{}
-
-  @doc false
-  def __build__(path, modes, line_or_bytes) do
-    raw = :lists.keyfind(:encoding, 1, modes) == false
-
-    modes =
-      case raw do
-        true ->
-          if :lists.keyfind(:read_ahead, 1, modes) == {:read_ahead, false} do
-            [:raw | modes]
-          else
-            [:raw, :read_ahead | modes]
-          end
-        false ->
-          modes
-      end
-
-    %File.Stream{path: path, modes: modes, raw: raw, line_or_bytes: line_or_bytes}
-  end
-
-  defimpl Collectable do
-    def into(%{path: path, modes: modes, raw: raw} = stream) do
-      modes = for mode <- modes, not mode in [:read], do: mode
-
-      case :file.open(path, [:write | modes]) do
-        {:ok, device} ->
-          {:ok, into(device, stream, raw)}
-        {:error, reason} ->
-          raise File.Error, reason: reason, action: "stream", path: path
-      end
-    end
-
-    defp into(device, stream, raw) do
-      fn
-        :ok, {:cont, x} ->
-          case raw do
-            true  -> IO.binwrite(device, x)
-            false -> IO.write(device, x)
-          end
-        :ok, :done ->
-          # If delayed_write option is used and the last write failed will
-          # MatchError here as {:error, _} is returned.
-          :ok = :file.close(device)
-          stream
-        :ok, :halt ->
-          # If delayed_write option is used and the last write failed will
-          # MatchError here as {:error, _} is returned.
-          :ok = :file.close(device)
-      end
-    end
-  end
-
-  defimpl Enumerable do
-    def reduce(%{path: path, modes: modes, line_or_bytes: line_or_bytes, raw: raw}, acc, fun) do
-      modes = for mode <- modes, not mode in [:write, :append], do: mode
-
-      start_fun =
-        fn ->
-          case :file.open(path, modes) do
-            {:ok, device}    -> device
-            {:error, reason} ->
-              raise File.Error, reason: reason, action: "stream", path: path
-          end
-        end
-
-      next_fun =
-        case raw do
-          true  -> &IO.each_binstream(&1, line_or_bytes)
-          false -> &IO.each_stream(&1, line_or_bytes)
-        end
-
-      Stream.resource(start_fun, next_fun, &:file.close/1).(acc, fun)
-    end
-
-    def count(_stream) do
-      {:error, __MODULE__}
-    end
-
-    def member?(_stream, _term) do
-      {:error, __MODULE__}
-    end
-  end
-end
@@ -1,422 +0,0 @@
-import Kernel, except: [round: 1]
-
-defmodule Float do
-  @moduledoc """
-  Functions for working with floating point numbers.
-  """
-
-  import Bitwise
-
-  @power_of_2_to_52 4503599627370496
-
-  @doc """
-  Parses a binary into a float.
-
-  If successful, returns a tuple in the form of `{float, remainder_of_binary}`;
-  when the binary cannot be coerced into a valid float, the atom `:error` is
-  returned.
-
-  If the size of float exceeds the maximum size of `1.7976931348623157e+308`,
-  the `ArgumentError` exception is raised.
-
-  If you want to convert a string-formatted float directly to a float,
-  `String.to_float/1` can be used instead.
-
-  ## Examples
-
-      iex> Float.parse("34")
-      {34.0, ""}
-      iex> Float.parse("34.25")
-      {34.25, ""}
-      iex> Float.parse("56.5xyz")
-      {56.5, "xyz"}
-
-      iex> Float.parse("pi")
-      :error
-
-  """
-  @spec parse(binary) :: {float, binary} | :error
-  def parse("-" <> binary) do
-    case parse_unsigned(binary) do
-      :error -> :error
-      {number, remainder} -> {-number, remainder}
-    end
-  end
-
-  def parse("+" <> binary) do
-    parse_unsigned(binary)
-  end
-
-  def parse(binary) do
-    parse_unsigned(binary)
-  end
-
-  defp parse_unsigned(<<digit, rest::binary>>) when digit in ?0..?9, do:
-    parse_unsigned(rest, false, false, <<digit>>)
-
-  defp parse_unsigned(binary) when is_binary(binary), do:
-    :error
-
-  defp parse_unsigned(<<digit, rest::binary>>, dot?, e?, acc) when digit in ?0..?9, do:
-    parse_unsigned(rest, dot?, e?, <<acc::binary, digit>>)
-
-  defp parse_unsigned(<<?., digit, rest::binary>>, false, false, acc) when digit in ?0..?9, do:
-    parse_unsigned(rest, true, false, <<acc::binary, ?., digit>>)
-
-  defp parse_unsigned(<<exp_marker, digit, rest::binary>>, dot?, false, acc) when exp_marker in 'eE' and  digit in ?0..?9, do:
-    parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, digit>>)
-
-  defp parse_unsigned(<<exp_marker, sign, digit, rest::binary>>, dot?, false, acc) when exp_marker in 'eE' and sign in '-+' and digit in ?0..?9, do:
-    parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, sign, digit>>)
-
-  defp parse_unsigned(rest, dot?, _e?, acc), do:
-    {:erlang.binary_to_float(add_dot(acc, dot?)), rest}
-
-  defp add_dot(acc, true),  do: acc
-  defp add_dot(acc, false), do: acc <> ".0"
-
-  @doc """
-  Rounds a float to the largest integer less than or equal to `num`.
-
-  `floor/2` also accepts a precision to round a floating point value down
-  to an arbitrary number of fractional digits (between 0 and 15).
-  The operation is performed on the binary floating point, without a
-  conversion to decimal.
-
-  The behaviour of `floor/2` for floats can be surprising. For example:
-
-      iex> Float.floor(12.52, 2)
-      12.51
-
-  One may have expected it to floor to 12.52. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as 12.51999999,
-  which explains the behaviour above.
-
-  This function always returns a float. `Kernel.trunc/1` may be used instead to
-  truncate the result to an integer afterwards.
-
-  ## Examples
-
-      iex> Float.floor(34.25)
-      34.0
-      iex> Float.floor(-56.5)
-      -57.0
-      iex> Float.floor(34.259, 2)
-      34.25
-
-  """
-  @spec floor(float, 0..15) :: float
-  def floor(number, precision \\ 0) when is_float(number) and precision in 0..15 do
-    round(number, precision, :floor)
-  end
-
-  @doc """
-  Rounds a float to the smallest integer greater than or equal to `num`.
-
-  `ceil/2` also accepts a precision to round a floating point value down
-  to an arbitrary number of fractional digits (between 0 and 15).
-
-  The operation is performed on the binary floating point, without a
-  conversion to decimal.
-
-  The behaviour of `ceil/2` for floats can be surprising. For example:
-
-      iex> Float.ceil(-12.52, 2)
-      -12.51
-
-  One may have expected it to ceil to -12.52. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as -12.51999999,
-  which explains the behaviour above.
-
-  This function always returns floats. `Kernel.trunc/1` may be used instead to
-  truncate the result to an integer afterwards.
-
-  ## Examples
-
-      iex> Float.ceil(34.25)
-      35.0
-      iex> Float.ceil(-56.5)
-      -56.0
-      iex> Float.ceil(34.251, 2)
-      34.26
-
-  """
-  @spec ceil(float, 0..15) :: float
-  def ceil(number, precision \\ 0) when is_float(number) and precision in 0..15 do
-    round(number, precision, :ceil)
-  end
-
-  @doc """
-  Rounds a floating point value to an arbitrary number of fractional
-  digits (between 0 and 15).
-
-  The rounding direction always ties to half up. The operation is
-  performed on the binary floating point, without a conversion to decimal.
-
-  This function only accepts floats and always returns a float. Use
-  `Kernel.round/1` if you want a function that accepts both floats
-  and integers and always returns an integer.
-
-  The behaviour of `round/2` for floats can be surprising. For example:
-
-      iex> Float.round(5.5675, 3)
-      5.567
-
-  One may have expected it to round to the half up 5.568. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as 5.567499999,
-  which explains the behaviour above. If you want exact rounding for decimals,
-  you must use a decimal library. The behaviour above is also in accordance
-  to reference implementations, such as "Correctly Rounded Binary-Decimal and
-  Decimal-Binary Conversions" by David M. Gay.
-
-  ## Examples
-
-      iex> Float.round(12.5)
-      13.0
-      iex> Float.round(5.5674, 3)
-      5.567
-      iex> Float.round(5.5675, 3)
-      5.567
-      iex> Float.round(-5.5674, 3)
-      -5.567
-      iex> Float.round(-5.5675)
-      -6.0
-      iex> Float.round(12.341444444444441, 15)
-      12.341444444444441
-
-  """
-  @spec round(float, 0..15) :: float
-
-  # This implementation is slow since it relies on big integers.
-  # Faster implementations are available on more recent papers
-  # and could be implemented in the future.
-  def round(float, precision \\ 0) when is_float(float) and precision in 0..15 do
-    round(float, precision, :half_up)
-  end
-
-  defp round(float, precision, rounding) do
-    <<sign::1, exp::11, significant::52-bitstring>> = <<float::float>>
-    {num, count, _} = decompose(significant)
-    count = count - exp + 1023
-
-    cond do
-      count <= 0 or  # There is no decimal precision
-      (0 == exp and <<0::52>> == significant) -> #zero or minus zero
-        float
-
-      count >= 104 -> # Precision beyond 15 digits
-        case rounding do
-          :ceil when sign === 0 -> 1 / power_of_10(precision)
-          :floor when sign === 1 -> -1 / power_of_10(precision)
-          _ -> 0.0
-        end
-
-      count <= precision -> # We are asking more precision than we have
-        float
-
-      true ->
-        # Difference in precision between float and asked precision
-        # We subtract 1 because we need to calculate the remainder too
-        diff = count - precision - 1
-
-        # Get up to latest so we calculate the remainder
-        power_of_10 = power_of_10(diff)
-
-        # Convert the numerand to decimal base
-        num = num * power_of_5(count)
-
-        # Move to the given precision - 1
-        num = div(num, power_of_10)
-        div = div(num, 10)
-        num = rounding(rounding, sign, num, div)
-
-        # Convert back to float without loss
-        # http://www.exploringbinary.com/correct-decimal-to-floating-point-using-big-integers/
-        den = power_of_10(precision)
-        boundary = den <<< 52
-
-        cond do
-          num == 0 ->
-            0.0
-          num >= boundary ->
-            {den, exp} = scale_down(num, boundary, 52)
-            decimal_to_float(sign, num, den, exp)
-          true ->
-            {num, exp} = scale_up(num, boundary, 52)
-            decimal_to_float(sign, num, den, exp)
-        end
-    end
-  end
-
-  defp scale_up(num, boundary, exp) when num >= boundary, do: {num, exp}
-  defp scale_up(num, boundary, exp), do: scale_up(num <<< 1, boundary, exp - 1)
-
-  defp scale_down(num, den, exp) do
-    new_den = den <<< 1
-    if num < new_den do
-      {den >>> 52, exp}
-    else
-      scale_down(num, new_den, exp + 1)
-    end
-  end
-
-  defp decimal_to_float(sign, num, den, exp) do
-    quo = div(num, den)
-    rem = num - quo * den
-
-    tmp =
-      case den >>> 1 do
-        den when rem > den -> quo + 1
-        den when rem < den -> quo
-        _ when (quo &&& 1) === 1 -> quo + 1
-        _ -> quo
-      end
-
-    tmp = tmp - @power_of_2_to_52
-    <<tmp::float>> = <<sign::1, (exp + 1023)::11, tmp::52>>
-    tmp
-  end
-
-  defp rounding(:floor, 1, _num, div), do: div + 1
-  defp rounding(:ceil, 0, _num, div), do: div + 1
-  defp rounding(:half_up, _sign, num, div) do
-    case rem(num, 10) do
-      rem when rem < 5 -> div
-      rem when rem >= 5 -> div + 1
-    end
-  end
-  defp rounding(_, _, _, div), do: div
-
-  Enum.reduce 0..104, 1, fn x, acc ->
-    defp power_of_10(unquote(x)), do: unquote(acc)
-    acc * 10
-  end
-
-  Enum.reduce 0..104, 1, fn x, acc ->
-    defp power_of_5(unquote(x)), do: unquote(acc)
-    acc * 5
-  end
-
-  @doc """
-  Returns a pair of integers whose ratio is exactly equal
-  to the original float and with a positive denominator.
-
-  ## Examples
-
-      iex> Float.ratio(3.14)
-      {7070651414971679, 2251799813685248}
-      iex> Float.ratio(-3.14)
-      {-7070651414971679, 2251799813685248}
-      iex> Float.ratio(1.5)
-      {3, 2}
-      iex> Float.ratio(-1.5)
-      {-3, 2}
-      iex> Float.ratio(16.0)
-      {16, 1}
-      iex> Float.ratio(-16.0)
-      {-16, 1}
-
-  """
-  def ratio(float) when is_float(float) do
-    <<sign::1, exp::11, significant::52-bitstring>> = <<float::float>>
-    {num, _, den} = decompose(significant)
-    num = sign(sign, num)
-    case exp - 1023 do
-      exp when exp > 0 ->
-        {den, exp} = shift_right(den, exp)
-        {shift_left(num, exp), den}
-      exp when exp < 0 ->
-        {num, shift_left(den, -exp)}
-      0 ->
-        {num, den}
-    end
-  end
-
-  defp decompose(significant) do
-    decompose(significant, 1, 0, 2, 1, 1)
-  end
-
-  defp decompose(<<1::1, bits::bitstring>>, count, last_count, power, _last_power, acc) do
-    decompose(bits, count + 1, count, power <<< 1, power, shift_left(acc, count - last_count) + 1)
-  end
-  defp decompose(<<0::1, bits::bitstring>>, count, last_count, power, last_power, acc) do
-    decompose(bits, count + 1, last_count, power <<< 1, last_power, acc)
-  end
-  defp decompose(<<>>, _count, last_count, _power, last_power, acc) do
-    {acc, last_count, last_power}
-  end
-
-  defp sign(0, num), do: num
-  defp sign(1, num), do: -num
-
-  defp shift_left(num, 0), do: num
-  defp shift_left(num, times), do: shift_left(num <<< 1, times - 1)
-
-  defp shift_right(num, 0), do: {num, 0}
-  defp shift_right(1, times), do: {1, times}
-  defp shift_right(num, times), do: shift_right(num >>> 1, times - 1)
-
-  @doc """
-  Returns a charlist which corresponds to the text representation
-  of the given float.
-
-  It uses the shortest representation according to algorithm described
-  in "Printing Floating-Point Numbers Quickly and Accurately" in
-  Proceedings of the SIGPLAN '96 Conference on Programming Language
-  Design and Implementation.
-
-  ## Examples
-
-      iex> Float.to_charlist(7.0)
-      '7.0'
-
-  """
-  @spec to_charlist(float) :: charlist
-  def to_charlist(float) when is_float(float) do
-    :io_lib_format.fwrite_g(float)
-  end
-
-  @doc """
-  Returns a binary which corresponds to the text representation
-  of the given float.
-
-  It uses the shortest representation according to algorithm described
-  in "Printing Floating-Point Numbers Quickly and Accurately" in
-  Proceedings of the SIGPLAN '96 Conference on Programming Language
-  Design and Implementation.
-
-  ## Examples
-
-      iex> Float.to_string(7.0)
-      "7.0"
-
-  """
-  @spec to_string(float) :: String.t
-  def to_string(float) when is_float(float) do
-    IO.iodata_to_binary(:io_lib_format.fwrite_g(float))
-  end
-
-  # TODO: Deprecate by v1.5
-  @doc false
-  def to_char_list(float), do: Float.to_charlist(float)
-
-  @doc false
-  def to_char_list(float, options) do
-    IO.warn "Float.to_char_list/2 is deprecated, use :erlang.float_to_list/2 instead"
-    :erlang.float_to_list(float, expand_compact(options))
-  end
-
-  @doc false
-  def to_string(float, options) do
-    IO.warn "Float.to_string/2 is deprecated, use :erlang.float_to_binary/2 instead"
-    :erlang.float_to_binary(float, expand_compact(options))
-  end
-
-  defp expand_compact([{:compact, false} | t]), do: expand_compact(t)
-  defp expand_compact([{:compact, true} | t]),  do: [:compact | expand_compact(t)]
-  defp expand_compact([h | t]),                 do: [h | expand_compact(t)]
-  defp expand_compact([]),                      do: []
-end
@@ -1,162 +0,0 @@
-defmodule GenEvent.Stream do
-  @moduledoc false
-  defstruct manager: nil, timeout: :infinity
-
-  @type t :: %__MODULE__{
-               manager: GenEvent.manager,
-               timeout: timeout}
-
-  @doc false
-  def init({_pid, _ref} = state) do
-    {:ok, state}
-  end
-
-  @doc false
-  def handle_event(event, _state) do
-    # We do this to trick Dialyzer to not complain about non-local returns.
-    case :erlang.phash2(1, 1) do
-      0 -> exit({:bad_event, event})
-      1 -> :remove_handler
-    end
-  end
-
-  @doc false
-  def handle_call(msg, _state) do
-    # We do this to trick Dialyzer to not complain about non-local returns.
-    reason = {:bad_call, msg}
-    case :erlang.phash2(1, 1) do
-      0 -> exit(reason)
-      1 -> {:remove_handler, reason}
-    end
-  end
-
-  @doc false
-  def handle_info(_msg, state) do
-    {:ok, state}
-  end
-
-  @doc false
-  def terminate(_reason, _state) do
-    :ok
-  end
-
-  @doc false
-  def code_change(_old, state, _extra) do
-    {:ok, state}
-  end
-end
-
-defimpl Enumerable, for: GenEvent.Stream do
-  def reduce(stream, acc, fun) do
-    start_fun = fn() -> start(stream) end
-    next_fun = &next(stream, &1)
-    stop_fun = &stop(stream, &1)
-    Stream.resource(start_fun, next_fun, stop_fun).(acc, wrap_reducer(fun))
-  end
-
-  def count(_stream) do
-    {:error, __MODULE__}
-  end
-
-  def member?(_stream, _item) do
-    {:error, __MODULE__}
-  end
-
-  defp wrap_reducer(fun) do
-    fn
-      {:ack, manager, ref, event}, acc ->
-        send manager, {ref, :ok}
-        fun.(event, acc)
-      {:async, _manager, _ref, event}, acc ->
-        fun.(event, acc)
-      {:sync, manager, ref, event}, acc ->
-        try do
-          fun.(event, acc)
-        after
-          send manager, {ref, :ok}
-        end
-    end
-  end
-
-  defp start(%{manager: manager} = stream) do
-    try do
-      {:ok, {pid, ref}} = :gen.call(manager, self(),
-                                    {:add_process_handler, self(), self()}, :infinity)
-      mon_ref = Process.monitor(pid)
-      {pid, ref, mon_ref}
-    catch
-      :exit, reason -> exit({reason, {__MODULE__, :start, [stream]}})
-    end
-  end
-
-  defp next(%{timeout: timeout} = stream, {pid, ref, mon_ref} = acc) do
-    self = self()
-
-    receive do
-      # Got an async event.
-      {_from, {^pid, ^ref}, {:notify, event}} ->
-        {[{:async, pid, ref, event}], acc}
-
-      # Got a sync event.
-      {_from, {^pid, ^ref}, {:sync_notify, event}} ->
-        {[{:sync, pid, ref, event}], acc}
-
-      # Got an ack event.
-      {_from, {^pid, ^ref}, {:ack_notify, event}} ->
-        {[{:ack, pid, ref, event}], acc}
-
-      # The handler was removed. Stop iteration, resolve the
-      # event later. We need to demonitor now, otherwise DOWN
-      # appears with higher priority in the shutdown process.
-      {:gen_event_EXIT, {^pid, ^ref}, _reason} = event ->
-        Process.demonitor(mon_ref, [:flush])
-        send(self, event)
-        {:halt, {:removed, acc}}
-
-      # The manager died. Stop iteration, resolve the event later.
-      {:DOWN, ^mon_ref, _, _, _} = event ->
-        send(self, event)
-        {:halt, {:removed, acc}}
-    after
-      timeout ->
-        exit({:timeout, {__MODULE__, :next, [stream, acc]}})
-    end
-  end
-
-  # If we reach this branch, we know the handler was already
-  # removed, so we don't trigger a request for doing so.
-  defp stop(stream, {:removed, {pid, ref, mon_ref} = acc}) do
-    case wait_for_handler_removal(pid, ref, mon_ref) do
-      :ok ->
-        flush_events(ref)
-      {:error, reason} ->
-        exit({reason, {__MODULE__, :stop, [stream, acc]}})
-    end
-  end
-
-  # If we reach this branch, the handler was not removed yet,
-  # so we trigger a request for doing so.
-  defp stop(stream, {pid, ref, _} = acc) do
-    _ = GenEvent.remove_handler(pid, {pid, ref}, :shutdown)
-    stop(stream, {:removed, acc})
-  end
-
-  defp wait_for_handler_removal(pid, ref, mon_ref) do
-    receive do
-      {:gen_event_EXIT, {^pid, ^ref}, _reason} ->
-        Process.demonitor(mon_ref, [:flush])
-        :ok
-      {:DOWN, ^mon_ref, _, _, reason} ->
-        {:error, reason}
-    end
-  end
-
-  defp flush_events(ref) do
-    receive do
-      {_from, {_pid, ^ref}, {notify, _event}} when notify in [:notify, :ack_notify, :sync_notify] ->
-        flush_events(ref)
-    after
-      0 -> :ok
-    end
-  end
-end
@@ -1,928 +0,0 @@
-defmodule GenServer do
-  @moduledoc """
-  A behaviour module for implementing the server of a client-server relation.
-
-  A GenServer is a process like any other Elixir process and it can be used
-  to keep state, execute code asynchronously and so on. The advantage of using
-  a generic server process (GenServer) implemented using this module is that it
-  will have a standard set of interface functions and include functionality for
-  tracing and error reporting. It will also fit into a supervision tree.
-
-  ## Example
-
-  The GenServer behaviour abstracts the common client-server interaction.
-  Developers are only required to implement the callbacks and functionality they are
-  interested in.
-
-  Let's start with a code example and then explore the available callbacks.
-  Imagine we want a GenServer that works like a stack, allowing us to push
-  and pop items:
-
-      defmodule Stack do
-        use GenServer
-
-        # Callbacks
-
-        def handle_call(:pop, _from, [h | t]) do
-          {:reply, h, t}
-        end
-
-        def handle_cast({:push, item}, state) do
-          {:noreply, [item | state]}
-        end
-      end
-
-      # Start the server
-      {:ok, pid} = GenServer.start_link(Stack, [:hello])
-
-      # This is the client
-      GenServer.call(pid, :pop)
-      #=> :hello
-
-      GenServer.cast(pid, {:push, :world})
-      #=> :ok
-
-      GenServer.call(pid, :pop)
-      #=> :world
-
-  We start our `Stack` by calling `start_link/3`, passing the module
-  with the server implementation and its initial argument (a list
-  representing the stack containing the item `:hello`). We can primarily
-  interact with the server by sending two types of messages. **call**
-  messages expect a reply from the server (and are therefore synchronous)
-  while **cast** messages do not.
-
-  Every time you do a `GenServer.call/3`, the client will send a message
-  that must be handled by the `c:handle_call/3` callback in the GenServer.
-  A `cast/2` message must be handled by `c:handle_cast/2`.
-
-  ## Callbacks
-
-  There are 6 callbacks required to be implemented in a `GenServer`. By
-  adding `use GenServer` to your module, Elixir will automatically define
-  all 6 callbacks for you, leaving it up to you to implement the ones
-  you want to customize.
-
-  ## Name Registration
-
-  Both `start_link/3` and `start/3` support the `GenServer` to register
-  a name on start via the `:name` option. Registered names are also
-  automatically cleaned up on termination. The supported values are:
-
-    * an atom - the GenServer is registered locally with the given name
-      using `Process.register/2`.
-
-    * `{:global, term}`- the GenServer is registered globally with the given
-      term using the functions in the `:global` module.
-
-    * `{:via, module, term}` - the GenServer is registered with the given
-      mechanism and name. The `:via` option expects a module that exports
-      `register_name/2`, `unregister_name/1`, `whereis_name/1` and `send/2`.
-      One such example is the `:global` module which uses these functions
-      for keeping the list of names of processes and their associated PIDs
-      that are available globally for a network of Elixir nodes. Elixir also
-      ships with a local, decentralized and scalable registry called `Registry`
-      for locally storing names that are generated dynamically.
-
-  For example, we could start and register our `Stack` server locally as follows:
-
-      # Start the server and register it locally with name MyStack
-      {:ok, _} = GenServer.start_link(Stack, [:hello], name: MyStack)
-
-      # Now messages can be sent directly to MyStack
-      GenServer.call(MyStack, :pop) #=> :hello
-
-  Once the server is started, the remaining functions in this module (`call/3`,
-  `cast/2`, and friends) will also accept an atom, or any `:global` or `:via`
-  tuples. In general, the following formats are supported:
-
-    * a `pid`
-    * an `atom` if the server is locally registered
-    * `{atom, node}` if the server is locally registered at another node
-    * `{:global, term}` if the server is globally registered
-    * `{:via, module, name}` if the server is registered through an alternative
-      registry
-
-  If there is an interest to register dynamic names locally, do not use
-  atoms, as atoms are never garbage collected and therefore dynamically
-  generated atoms won't be garbage collected. For such cases, you can
-  set up your own local registry by using the `Registry` module.
-
-  ## Client / Server APIs
-
-  Although in the example above we have used `GenServer.start_link/3` and
-  friends to directly start and communicate with the server, most of the
-  time we don't call the `GenServer` functions directly. Instead, we wrap
-  the calls in new functions representing the public API of the server.
-
-  Here is a better implementation of our Stack module:
-
-      defmodule Stack do
-        use GenServer
-
-        # Client
-
-        def start_link(default) do
-          GenServer.start_link(__MODULE__, default)
-        end
-
-        def push(pid, item) do
-          GenServer.cast(pid, {:push, item})
-        end
-
-        def pop(pid) do
-          GenServer.call(pid, :pop)
-        end
-
-        # Server (callbacks)
-
-        def handle_call(:pop, _from, [h | t]) do
-          {:reply, h, t}
-        end
-
-        def handle_call(request, from, state) do
-          # Call the default implementation from GenServer
-          super(request, from, state)
-        end
-
-        def handle_cast({:push, item}, state) do
-          {:noreply, [item | state]}
-        end
-
-        def handle_cast(request, state) do
-          super(request, state)
-        end
-      end
-
-  In practice, it is common to have both server and client functions in
-  the same module. If the server and/or client implementations are growing
-  complex, you may want to have them in different modules.
-
-  ## Receiving "regular" messages
-
-  The goal of a `GenServer` is to abstract the "receive" loop for developers,
-  automatically handling system messages, support code change, synchronous
-  calls and more. Therefore, you should never call your own "receive" inside
-  the GenServer callbacks as doing so will cause the GenServer to misbehave.
-
-  Besides the synchronous and asynchronous communication provided by `call/3`
-  and `cast/2`, "regular" messages sent by functions such `Kernel.send/2`,
-  `Process.send_after/4` and similar, can be handled inside the `c:handle_info/2`
-  callback.
-
-  `c:handle_info/2` can be used in many situations, such as handling monitor
-  DOWN messages sent by `Process.monitor/1`. Another use case for `c:handle_info/2`
-  is to perform periodic work, with the help of `Process.send_after/4`:
-
-      defmodule MyApp.Periodically do
-        use GenServer
-
-        def start_link do
-          GenServer.start_link(__MODULE__, %{})
-        end
-
-        def init(state) do
-          schedule_work() # Schedule work to be performed on start
-          {:ok, state}
-        end
-
-        def handle_info(:work, state) do
-          # Do the desired work here
-          schedule_work() # Reschedule once more
-          {:noreply, state}
-        end
-
-        defp schedule_work() do
-          Process.send_after(self(), :work, 2 * 60 * 60 * 1000) # In 2 hours
-        end
-      end
-
-  ## Debugging with the :sys module
-
-  GenServers, as [special processes](http://erlang.org/doc/design_principles/spec_proc.html),
-  can be debugged using the `:sys` module. Through various hooks, this module
-  allows developers to introspect the state of the process and trace
-  system events that happen during its execution, such as received messages,
-  sent replies and state changes.
-
-  Let's explore the basic functions from the `:sys` module used for debugging:
-
-    * [`:sys.get_state/2`](http://erlang.org/doc/man/sys.html#get_state-2) -
-      allows retrieval of the state of the process. In the case of
-      a GenServer process, it will be the callback module state, as
-      passed into the callback functions as last argument.
-    * [`:sys.get_status/2`](http://erlang.org/doc/man/sys.html#get_status-2) -
-      allows retrieval of the status of the process. This status includes
-      the process dictionary, if the process is running or is suspended,
-      the parent PID, the debugger state, and the state of the behaviour module,
-      which includes the callback module state (as returned by `:sys.get_state/2`).
-      It's possible to change how this status is represented by defining
-      the optional `c:GenServer.format_status/2` callback.
-    * [`:sys.trace/3`](http://erlang.org/doc/man/sys.html#trace-3) -
-      prints all the system events to `:stdio`.
-    * [`:sys.statistics/3`](http://erlang.org/doc/man/sys.html#statistics-3) -
-      manages collection of process statistics.
-    * [`:sys.no_debug/2`](http://erlang.org/doc/man/sys.html#no_debug-2) -
-      turns off all debug handlers for the given process. It is very important
-      to switch off debugging once we're done. Excessive debug handlers or
-      those that should be turned off, but weren't, can seriously damage
-      the performance of the system.
-
-  Let's see how we could use those functions for debugging the stack server
-  we defined earlier.
-
-      iex> {:ok, pid} = Stack.start_link([])
-      iex> :sys.statistics(pid, true) # turn on collecting process statistics
-      iex> :sys.trace(pid, true) # turn on event printing
-      iex> Stack.push(pid, 1)
-      *DBG* <0.122.0> got cast {push,1}
-      *DBG* <0.122.0> new state [1]
-      :ok
-      iex> :sys.get_state(pid)
-      [1]
-      iex> Stack.pop(pid)
-      *DBG* <0.122.0> got call pop from <0.80.0>
-      *DBG* <0.122.0> sent 1 to <0.80.0>, new state []
-      1
-      iex> :sys.statistics(pid, :get)
-      {:ok,
-       [start_time: {{2016, 7, 16}, {12, 29, 41}},
-        current_time: {{2016, 7, 16}, {12, 29, 50}},
-        reductions: 117, messages_in: 2, messages_out: 0]}
-      iex> :sys.no_debug(pid) # turn off all debug handlers
-      :ok
-      iex> :sys.get_status(pid)
-      {:status, #PID<0.122.0>, {:module, :gen_server},
-       [["$initial_call": {Stack, :init, 1},            # pdict
-         "$ancestors": [#PID<0.80.0>, #PID<0.51.0>]],
-        :running,                                       # :running | :suspended
-        #PID<0.80.0>,                                   # parent
-        [],                                             # debugger state
-        [header: 'Status for generic server <0.122.0>', # module status
-         data: [{'Status', :running}, {'Parent', #PID<0.80.0>},
-           {'Logged events', []}], data: [{'State', [1]}]]]}
-
-  ## Learn more
-
-  If you wish to find out more about gen servers, the Elixir Getting Started
-  guide provides a tutorial-like introduction. The documentation and links
-  in Erlang can also provide extra insight.
-
-    * [GenServer – Elixir's Getting Started Guide](http://elixir-lang.org/getting-started/mix-otp/genserver.html)
-    * [`:gen_server` module documentation](http://www.erlang.org/doc/man/gen_server.html)
-    * [gen_server Behaviour – OTP Design Principles](http://www.erlang.org/doc/design_principles/gen_server_concepts.html)
-    * [Clients and Servers – Learn You Some Erlang for Great Good!](http://learnyousomeerlang.com/clients-and-servers)
-  """
-
-  @doc """
-  Invoked when the server is started. `start_link/3` or `start/3` will
-  block until it returns.
-
-  `args` is the argument term (second argument) passed to `start_link/3`.
-
-  Returning `{:ok, state}` will cause `start_link/3` to return
-  `{:ok, pid}` and the process to enter its loop.
-
-  Returning `{:ok, state, timeout}` is similar to `{:ok, state}`
-  except `handle_info(:timeout, state)` will be called after `timeout`
-  milliseconds if no messages are received within the timeout.
-
-  Returning `{:ok, state, :hibernate}` is similar to
-  `{:ok, state}` except the process is hibernated before entering the loop. See
-  `c:handle_call/3` for more information on hibernation.
-
-  Returning `:ignore` will cause `start_link/3` to return `:ignore` and the
-  process will exit normally without entering the loop or calling `c:terminate/2`.
-  If used when part of a supervision tree the parent supervisor will not fail
-  to start nor immediately try to restart the `GenServer`. The remainder of the
-  supervision tree will be (re)started and so the `GenServer` should not be
-  required by other processes. It can be started later with
-  `Supervisor.restart_child/2` as the child specification is saved in the parent
-  supervisor. The main use cases for this are:
-
-    * The `GenServer` is disabled by configuration but might be enabled later.
-    * An error occurred and it will be handled by a different mechanism than the
-     `Supervisor`. Likely this approach involves calling `Supervisor.restart_child/2`
-      after a delay to attempt a restart.
-
-  Returning `{:stop, reason}` will cause `start_link/3` to return
-  `{:error, reason}` and the process to exit with reason `reason` without
-  entering the loop or calling `c:terminate/2`.
-  """
-  @callback init(args :: term) ::
-    {:ok, state} |
-    {:ok, state, timeout | :hibernate} |
-    :ignore |
-    {:stop, reason :: any} when state: any
-
-  @doc """
-  Invoked to handle synchronous `call/3` messages. `call/3` will block until a
-  reply is received (unless the call times out or nodes are disconnected).
-
-  `request` is the request message sent by a `call/3`, `from` is a 2-tuple
-  containing the caller's PID and a term that uniquely identifies the call, and
-  `state` is the current state of the `GenServer`.
-
-  Returning `{:reply, reply, new_state}` sends the response `reply` to the
-  caller and continues the loop with new state `new_state`.
-
-  Returning `{:reply, reply, new_state, timeout}` is similar to
-  `{:reply, reply, new_state}` except `handle_info(:timeout, new_state)` will be
-  called after `timeout` milliseconds if no messages are received.
-
-  Returning `{:reply, reply, new_state, :hibernate}` is similar to
-  `{:reply, reply, new_state}` except the process is hibernated and will
-  continue the loop once a message is in its message queue. If a message is
-  already in the message queue this will be immediately. Hibernating a
-  `GenServer` causes garbage collection and leaves a continuous heap that
-  minimises the memory used by the process.
-
-  Hibernating should not be used aggressively as too much time could be spent
-  garbage collecting. Normally it should only be used when a message is not
-  expected soon and minimising the memory of the process is shown to be
-  beneficial.
-
-  Returning `{:noreply, new_state}` does not send a response to the caller and
-  continues the loop with new state `new_state`. The response must be sent with
-  `reply/2`.
-
-  There are three main use cases for not replying using the return value:
-
-    * To reply before returning from the callback because the response is known
-      before calling a slow function.
-    * To reply after returning from the callback because the response is not yet
-      available.
-    * To reply from another process, such as a task.
-
-  When replying from another process the `GenServer` should exit if the other
-  process exits without replying as the caller will be blocking awaiting a
-  reply.
-
-  Returning `{:noreply, new_state, timeout | :hibernate}` is similar to
-  `{:noreply, new_state}` except a timeout or hibernation occurs as with a
-  `:reply` tuple.
-
-  Returning `{:stop, reason, reply, new_state}` stops the loop and `c:terminate/2`
-  is called with reason `reason` and state `new_state`. Then the `reply` is sent
-  as the response to call and the process exits with reason `reason`.
-
-  Returning `{:stop, reason, new_state}` is similar to
-  `{:stop, reason, reply, new_state}` except a reply is not sent.
-
-  If this callback is not implemented, the default implementation by
-  `use GenServer` will return `{:stop, {:bad_call, request}, state}`.
-  """
-  @callback handle_call(request :: term, from, state :: term) ::
-    {:reply, reply, new_state} |
-    {:reply, reply, new_state, timeout | :hibernate} |
-    {:noreply, new_state} |
-    {:noreply, new_state, timeout | :hibernate} |
-    {:stop, reason, reply, new_state} |
-    {:stop, reason, new_state} when reply: term, new_state: term, reason: term
-
-  @doc """
-  Invoked to handle asynchronous `cast/2` messages.
-
-  `request` is the request message sent by a `cast/2` and `state` is the current
-  state of the `GenServer`.
-
-  Returning `{:noreply, new_state}` continues the loop with new state `new_state`.
-
-  Returning `{:noreply, new_state, timeout}` is similar to
-  `{:noreply, new_state}` except `handle_info(:timeout, new_state)` will be
-  called after `timeout` milliseconds if no messages are received.
-
-  Returning `{:noreply, new_state, :hibernate}` is similar to
-  `{:noreply, new_state}` except the process is hibernated before continuing the
-  loop. See `c:handle_call/3` for more information.
-
-  Returning `{:stop, reason, new_state}` stops the loop and `c:terminate/2` is
-  called with the reason `reason` and state `new_state`. The process exits with
-  reason `reason`.
-
-  If this callback is not implemented, the default implementation by
-  `use GenServer` will return `{:stop, {:bad_cast, request}, state}`.
-  """
-  @callback handle_cast(request :: term, state :: term) ::
-    {:noreply, new_state} |
-    {:noreply, new_state, timeout | :hibernate} |
-    {:stop, reason :: term, new_state} when new_state: term
-
-  @doc """
-  Invoked to handle all other messages.
-
-  `msg` is the message and `state` is the current state of the `GenServer`. When
-  a timeout occurs the message is `:timeout`.
-
-  Return values are the same as `c:handle_cast/2`.
-
-  If this callback is not implemented, the default implementation by
-  `use GenServer` will return `{:noreply, state}`.
-  """
-  @callback handle_info(msg :: :timeout | term, state :: term) ::
-    {:noreply, new_state} |
-    {:noreply, new_state, timeout | :hibernate} |
-    {:stop, reason :: term, new_state} when new_state: term
-
-  @doc """
-  Invoked when the server is about to exit. It should do any cleanup required.
-
-  `reason` is exit reason and `state` is the current state of the `GenServer`.
-  The return value is ignored.
-
-  `c:terminate/2` is called if a callback (except `c:init/1`) returns a `:stop`
-  tuple, raises, calls `Kernel.exit/1` or returns an invalid value. It may also
-  be called if the `GenServer` traps exits using `Process.flag/2` *and* the
-  parent process sends an exit signal.
-
-  If part of a supervision tree a `GenServer`'s `Supervisor` will send an exit
-  signal when shutting it down. The exit signal is based on the shutdown
-  strategy in the child's specification. If it is `:brutal_kill` the `GenServer`
-  is killed and so `c:terminate/2` is not called. However if it is a timeout the
-  `Supervisor` will send the exit signal `:shutdown` and the `GenServer` will
-  have the duration of the timeout to call `c:terminate/2` - if the process is
-  still alive after the timeout it is killed.
-
-  If the `GenServer` receives an exit signal (that is not `:normal`) from any
-  process when it is not trapping exits it will exit abruptly with the same
-  reason and so not call `c:terminate/2`. Note that a process does *NOT* trap
-  exits by default and an exit signal is sent when a linked process exits or its
-  node is disconnected.
-
-  Therefore it is not guaranteed that `c:terminate/2` is called when a `GenServer`
-  exits. For such reasons, we usually recommend important clean-up rules to
-  happen in separated processes either by use of monitoring or by links
-  themselves. For example if the `GenServer` controls a `port` (e.g.
-  `:gen_tcp.socket`) or `t:File.io_device/0`, they will be closed on receiving a
-  `GenServer`'s exit signal and do not need to be closed in `c:terminate/2`.
-
-  If `reason` is not `:normal`, `:shutdown` nor `{:shutdown, term}` an error is
-  logged.
-  """
-  @callback terminate(reason, state :: term) ::
-    term when reason: :normal | :shutdown | {:shutdown, term} | term
-
-  @doc """
-  Invoked to change the state of the `GenServer` when a different version of a
-  module is loaded (hot code swapping) and the state's term structure should be
-  changed.
-
-  `old_vsn` is the previous version of the module (defined by the `@vsn`
-  attribute) when upgrading. When downgrading the previous version is wrapped in
-  a 2-tuple with first element `:down`. `state` is the current state of the
-  `GenServer` and `extra` is any extra data required to change the state.
-
-  Returning `{:ok, new_state}` changes the state to `new_state` and the code
-  change is successful.
-
-  Returning `{:error, reason}` fails the code change with reason `reason` and
-  the state remains as the previous state.
-
-  If `c:code_change/3` raises the code change fails and the loop will continue
-  with its previous state. Therefore this callback does not usually contain side effects.
-  """
-  @callback code_change(old_vsn, state :: term, extra :: term) ::
-    {:ok, new_state :: term} |
-    {:error, reason :: term} when old_vsn: term | {:down, term}
-
-  @doc """
-  Invoked in some cases to retrieve a formatted version of the `GenServer` status.
-
-  This callback can be useful to control the *appearance* of the status of the
-  `GenServer`. For example, it can be used to return a compact representation of
-  the `GenServer`'s state to avoid having large state terms printed.
-
-    * one of `:sys.get_status/1` or `:sys.get_status/2` is invoked to get the
-      status of the `GenServer`; in such cases, `reason` is `:normal`
-
-    * the `GenServer` terminates abnormally and logs an error; in such cases,
-      `reason` is `:terminate`
-
-  `pdict_and_state` is a two-elements list `[pdict, state]` where `pdict` is a
-  list of `{key, value}` tuples representing the current process dictionary of
-  the `GenServer` and `state` is the current state of the `GenServer`.
-  """
-  @callback format_status(reason, pdict_and_state :: list) ::
-    term when reason: :normal | :terminate
-
-  @optional_callbacks format_status: 2
-
-  @typedoc "Return values of `start*` functions"
-  @type on_start :: {:ok, pid} | :ignore | {:error, {:already_started, pid} | term}
-
-  @typedoc "The GenServer name"
-  @type name :: atom | {:global, term} | {:via, module, term}
-
-  @typedoc "Options used by the `start*` functions"
-  @type options :: [option]
-
-  @typedoc "Option values used by the `start*` functions"
-  @type option :: {:debug, debug} |
-                  {:name, name} |
-                  {:timeout, timeout} |
-                  {:spawn_opt, Process.spawn_opt}
-
-  @typedoc "Debug options supported by the `start*` functions"
-  @type debug :: [:trace | :log | :statistics | {:log_to_file, Path.t}]
-
-  @typedoc "The server reference"
-  @type server :: pid | name | {atom, node}
-
-  @typedoc """
-  Tuple describing the client of a call request.
-
-  `pid` is the PID of the caller and `tag` is a unique term used to identify the
-  call.
-  """
-  @type from :: {pid, tag :: term}
-
-  @doc false
-  defmacro __using__(_) do
-    quote location: :keep do
-      @behaviour GenServer
-
-      @doc false
-      def init(args) do
-        {:ok, args}
-      end
-
-      @doc false
-      def handle_call(msg, _from, state) do
-        proc =
-          case Process.info(self(), :registered_name) do
-            {_, []}   -> self()
-            {_, name} -> name
-          end
-
-        # We do this to trick Dialyzer to not complain about non-local returns.
-        case :erlang.phash2(1, 1) do
-          0 -> raise "attempted to call GenServer #{inspect proc} but no handle_call/3 clause was provided"
-          1 -> {:stop, {:bad_call, msg}, state}
-        end
-      end
-
-      @doc false
-      def handle_info(msg, state) do
-        proc =
-          case Process.info(self(), :registered_name) do
-            {_, []}   -> self()
-            {_, name} -> name
-          end
-        :error_logger.warning_msg('~p ~p received unexpected message in handle_info/2: ~p~n',
-                                  [__MODULE__, proc, msg])
-        {:noreply, state}
-      end
-
-      @doc false
-      def handle_cast(msg, state) do
-        proc =
-          case Process.info(self(), :registered_name) do
-            {_, []}   -> self()
-            {_, name} -> name
-          end
-
-        # We do this to trick Dialyzer to not complain about non-local returns.
-        case :erlang.phash2(1, 1) do
-          0 -> raise "attempted to cast GenServer #{inspect proc} but no handle_cast/2 clause was provided"
-          1 -> {:stop, {:bad_cast, msg}, state}
-        end
-      end
-
-      @doc false
-      def terminate(_reason, _state) do
-        :ok
-      end
-
-      @doc false
-      def code_change(_old, state, _extra) do
-        {:ok, state}
-      end
-
-      defoverridable [init: 1, handle_call: 3, handle_info: 2,
-                      handle_cast: 2, terminate: 2, code_change: 3]
-    end
-  end
-
-  @doc """
-  Starts a `GenServer` process linked to the current process.
-
-  This is often used to start the `GenServer` as part of a supervision tree.
-
-  Once the server is started, the `c:init/1` function of the given `module` is
-  called with `args` as its arguments to initialize the server. To ensure a
-  synchronized start-up procedure, this function does not return until `c:init/1`
-  has returned.
-
-  Note that a `GenServer` started with `start_link/3` is linked to the
-  parent process and will exit in case of crashes from the parent. The GenServer
-  will also exit due to the `:normal` reasons in case it is configured to trap
-  exits in the `c:init/1` callback.
-
-  ## Options
-
-    * `:name` - used for name registration as described in the "Name
-      registration" section of the module documentation
-
-    * `:timeout` - if present, the server is allowed to spend the given amount of
-      milliseconds initializing or it will be terminated and the start function
-      will return `{:error, :timeout}`
-
-    * `:debug` - if present, the corresponding function in the [`:sys`
-      module](http://www.erlang.org/doc/man/sys.html) is invoked
-
-    * `:spawn_opt` - if present, its value is passed as options to the
-      underlying process as in `Process.spawn/4`
-
-  ## Return values
-
-  If the server is successfully created and initialized, this function returns
-  `{:ok, pid}`, where `pid` is the PID of the server. If a process with the
-  specified server name already exists, this function returns
-  `{:error, {:already_started, pid}}` with the PID of that process.
-
-  If the `c:init/1` callback fails with `reason`, this function returns
-  `{:error, reason}`. Otherwise, if it returns `{:stop, reason}`
-  or `:ignore`, the process is terminated and this function returns
-  `{:error, reason}` or `:ignore`, respectively.
-  """
-  @spec start_link(module, any, options) :: on_start
-  def start_link(module, args, options \\ []) when is_atom(module) and is_list(options) do
-    do_start(:link, module, args, options)
-  end
-
-  @doc """
-  Starts a `GenServer` process without links (outside of a supervision tree).
-
-  See `start_link/3` for more information.
-  """
-  @spec start(module, any, options) :: on_start
-  def start(module, args, options \\ []) when is_atom(module) and is_list(options) do
-    do_start(:nolink, module, args, options)
-  end
-
-  defp do_start(link, module, args, options) do
-    case Keyword.pop(options, :name) do
-      {nil, opts} ->
-        :gen.start(:gen_server, link, module, args, opts)
-      {atom, opts} when is_atom(atom) ->
-        :gen.start(:gen_server, link, {:local, atom}, module, args, opts)
-      {{:global, _term} = tuple, opts} ->
-        :gen.start(:gen_server, link, tuple, module, args, opts)
-      {{:via, via_module, _term} = tuple, opts} when is_atom(via_module) ->
-        :gen.start(:gen_server, link, tuple, module, args, opts)
-      other ->
-        raise ArgumentError, """
-        expected :name option to be one of:
-
-          * nil
-          * atom
-          * {:global, term}
-          * {:via, module, term}
-
-        Got: #{inspect(other)}
-        """
-    end
-  end
-
-  @doc """
-  Stops the server with the given `reason`.
-
-  The `c:terminate/2` callback of the given `server` will be invoked before
-  exiting. This function returns `:ok` if the server terminates with the
-  given reason; if it terminates with another reason, the call exits.
-
-  This function keeps OTP semantics regarding error reporting.
-  If the reason is any other than `:normal`, `:shutdown` or
-  `{:shutdown, _}`, an error report is logged.
-  """
-  @spec stop(server, reason :: term, timeout) :: :ok
-  def stop(server, reason \\ :normal, timeout \\ :infinity) do
-    :gen.stop(server, reason, timeout)
-  end
-
-  @doc """
-  Makes a synchronous call to the `server` and waits for its reply.
-
-  The client sends the given `request` to the server and waits until a reply
-  arrives or a timeout occurs. `c:handle_call/3` will be called on the server
-  to handle the request.
-
-  `server` can be any of the values described in the "Name registration"
-  section of the documentation for this module.
-
-  ## Timeouts
-
-  `timeout` is an integer greater than zero which specifies how many
-  milliseconds to wait for a reply, or the atom `:infinity` to wait
-  indefinitely. The default value is `5000`. If no reply is received within
-  the specified time, the function call fails and the caller exits. If the
-  caller catches the failure and continues running, and the server is just late
-  with the reply, it may arrive at any time later into the caller's message
-  queue. The caller must in this case be prepared for this and discard any such
-  garbage messages that are two-element tuples with a reference as the first
-  element.
-  """
-  @spec call(server, term, timeout) :: term
-  def call(server, request, timeout \\ 5000) do
-    case whereis(server) do
-      nil ->
-        exit({:noproc, {__MODULE__, :call, [server, request, timeout]}})
-      pid when pid == self() ->
-        exit({:calling_self, {__MODULE__, :call, [server, request, timeout]}})
-      pid ->
-        try do
-          :gen.call(pid, :"$gen_call", request, timeout)
-        catch
-          :exit, reason ->
-            exit({reason, {__MODULE__, :call, [server, request, timeout]}})
-        else
-          {:ok, res} -> res
-        end
-    end
-  end
-
-  @doc """
-  Sends an asynchronous request to the `server`.
-
-  This function always returns `:ok` regardless of whether
-  the destination `server` (or node) exists. Therefore it
-  is unknown whether the destination `server` successfully
-  handled the message.
-
-  `c:handle_cast/2` will be called on the server to handle
-  the request. In case the `server` is on a node which is
-  not yet connected to the caller one, the call is going to
-  block until a connection happens. This is different than
-  the behaviour in OTP's `:gen_server` where the message
-  is sent by another process in this case, which could cause
-  messages to other nodes to arrive out of order.
-  """
-  @spec cast(server, term) :: :ok
-  def cast(server, request)
-
-  def cast({:global, name}, request) do
-    try do
-      :global.send(name, cast_msg(request))
-      :ok
-    catch
-      _, _ -> :ok
-    end
-  end
-
-  def cast({:via, mod, name}, request) do
-    try do
-      mod.send(name, cast_msg(request))
-      :ok
-    catch
-      _, _ -> :ok
-    end
-  end
-
-  def cast({name, node}, request) when is_atom(name) and is_atom(node),
-    do: do_send({name, node}, cast_msg(request))
-
-  def cast(dest, request) when is_atom(dest) or is_pid(dest),
-    do: do_send(dest, cast_msg(request))
-
-  @doc """
-  Casts all servers locally registered as `name` at the specified nodes.
-
-  This function returns immediately and ignores nodes that do not exist, or where the
-  server name does not exist.
-
-  See `multi_call/4` for more information.
-  """
-  @spec abcast([node], name :: atom, term) :: :abcast
-  def abcast(nodes \\ [node() | Node.list()], name, request) when is_list(nodes) and is_atom(name) do
-    msg = cast_msg(request)
-    _   = for node <- nodes, do: do_send({name, node}, msg)
-    :abcast
-  end
-
-  defp cast_msg(req) do
-    {:"$gen_cast", req}
-  end
-
-  defp do_send(dest, msg) do
-    try do
-      send(dest, msg)
-      :ok
-    catch
-      _, _ -> :ok
-    end
-  end
-
-  @doc """
-  Calls all servers locally registered as `name` at the specified `nodes`.
-
-  First, the `request` is sent to every node in `nodes`; then, the caller waits
-  for the replies. This function returns a two-element tuple `{replies,
-  bad_nodes}` where:
-
-    * `replies` - is a list of `{node, reply}` tuples where `node` is the node
-      that replied and `reply` is its reply
-    * `bad_nodes` - is a list of nodes that either did not exist or where a
-      server with the given `name` did not exist or did not reply
-
-  `nodes` is a list of node names to which the request is sent. The default
-  value is the list of all known nodes (including this node).
-
-  To avoid that late answers (after the timeout) pollute the caller's message
-  queue, a middleman process is used to do the actual calls. Late answers will
-  then be discarded when they arrive to a terminated process.
-
-  ## Examples
-
-  Assuming the `Stack` GenServer mentioned in the docs for the `GenServer`
-  module is registered as `Stack` in the `:"foo@my-machine"` and
-  `:"bar@my-machine"` nodes:
-
-      GenServer.multi_call(Stack, :pop)
-      #=> {[{:"foo@my-machine", :hello}, {:"bar@my-machine", :world}], []}
-
-  """
-  @spec multi_call([node], name :: atom, term, timeout) ::
-                  {replies :: [{node, term}], bad_nodes :: [node]}
-  def multi_call(nodes \\ [node() | Node.list()], name, request, timeout \\ :infinity) do
-    :gen_server.multi_call(nodes, name, request, timeout)
-  end
-
-  @doc """
-  Replies to a client.
-
-  This function can be used to explicitly send a reply to a client that called
-  `call/3` or `multi_call/4` when the reply cannot be specified in the return
-  value of `c:handle_call/3`.
-
-  `client` must be the `from` argument (the second argument) accepted by
-  `c:handle_call/3` callbacks. `reply` is an arbitrary term which will be given
-  back to the client as the return value of the call.
-
-  Note that `reply/2` can be called from any process, not just the GenServer
-  that originally received the call (as long as that GenServer communicated the
-  `from` argument somehow).
-
-  This function always returns `:ok`.
-
-  ## Examples
-
-      def handle_call(:reply_in_one_second, from, state) do
-        Process.send_after(self(), {:reply, from}, 1_000)
-        {:noreply, state}
-      end
-
-      def handle_info({:reply, from}, state) do
-        GenServer.reply(from, :one_second_has_passed)
-        {:noreply, state}
-      end
-
-  """
-  @spec reply(from, term) :: :ok
-  def reply(client, reply)
-
-  def reply({to, tag}, reply) when is_pid(to) do
-    try do
-      send(to, {tag, reply})
-      :ok
-    catch
-      _, _ -> :ok
-    end
-  end
-
-  @doc """
-  Returns the `pid` or `{name, node}` of a GenServer process, or `nil` if
-  no process is associated with the given name.
-
-  ## Examples
-
-  For example, to lookup a server process, monitor it and send a cast to it:
-
-      process = GenServer.whereis(server)
-      monitor = Process.monitor(process)
-      GenServer.cast(process, :hello)
-
-  """
-  @spec whereis(server) :: pid | {atom, node} | nil
-  def whereis(pid) when is_pid(pid), do: pid
-  def whereis(name) when is_atom(name) do
-    Process.whereis(name)
-  end
-  def whereis({:global, name}) do
-    case :global.whereis_name(name) do
-      pid when is_pid(pid) -> pid
-      :undefined           -> nil
-    end
-  end
-  def whereis({:via, mod, name}) do
-    case apply(mod, :whereis_name, [name]) do
-      pid when is_pid(pid) -> pid
-      :undefined           -> nil
-    end
-  end
-  def whereis({name, local}) when is_atom(name) and local == node() do
-    Process.whereis(name)
-  end
-  def whereis({name, node} = server) when is_atom(name) and is_atom(node) do
-    server
-  end
-end
@@ -0,0 +1,48 @@
+defmodule GenServer.Behavior do
+  @doc """
+  By using this module, you get default GenServer callbacks
+  for `handle_call`, `handle_info`, `handle_cast`, `terminate`
+  and `code_change`. `init` still needs to be implemented by the
+  developer. Since these functions are defined as overridable,
+  they can be partially customized and have a global clause
+  that simply invokes `super`. See `ExUnit.Server` for some
+  code examples.
+
+  This module also tags the behavior as :gen_server. For more
+  information on gen_server, please refer to the Erlang
+  documentation:
+
+  http://www.erlang.org/doc/man/gen_server.html
+  http://www.erlang.org/doc/design_principles/gen_server_concepts.html
+
+  """
+  defmacro __using__(_) do
+    quote location: :keep do
+      @behavior :gen_server
+
+      def handle_call(_request, _from, state) do
+        { :reply, :undef, state }
+      end
+
+      def handle_info(_msg, state) do
+        { :noreply, state }
+      end
+
+      def handle_cast(_msg, state) do
+        { :noreply, state }
+      end
+
+      def terminate(reason, state) do
+        :error_logger.error_report('#{inspect __MODULE__} crashed:\n#{inspect reason}')
+        :error_logger.error_report('#{inspect __MODULE__} snapshot:\n#{inspect state}')
+        :ok
+      end
+
+      def code_change(_old, state, _extra) do
+        { :ok, state }
+      end
+
+      defoverridable [handle_call: 3, handle_info: 2, handle_cast: 2, terminate: 2, code_change: 3]
+    end
+  end
+end
@@ -1,245 +1,81 @@
+defimpl Dict, for: HashDict do
+  defmacrop dict(data) do
+    quote do
+      { HashDict, unquote(data) }
+    end
+  end
+
+  def keys(dict(data)) do
+    :dict.fetch_keys data
+  end
+
+  def values(dict(data)) do
+    :dict.fold fn _key, value, acc ->
+      [value|acc]
+    end, [], data
+  end
+
+  def size(dict(data)) do
+    :dict.size data
+  end
+
+  def has_key?(dict(data), key) do
+    :dict.is_key key, data
+  end
+
+  def get(dict(data), key, default // nil) do
+    case :dict.find(key, data) do
+      {:ok, value} ->
+        value
+      :error ->
+        default
+    end
+  end
+
+  def put(dict(data), key, value) do
+    dict(:dict.store key, value, data)
+  end
+
+  def delete(dict(data), key) do
+    dict(:dict.erase key, data)
+  end
+
+  def merge(dict(d1), dict(d2)) do
+    dict(:dict.merge fn _k, _v1, v2 -> v2 end, d1, d2)
+  end
+
+  def merge(dict(d1), dict(d2), fun) do
+    dict(:dict.merge fun, d1, d2)
+  end
+
+  def update(dict(data), key, fun) do
+    dict(:dict.update key, fun, data)
+  end
+
+  def update(dict(data), key, initial, fun) do
+    dict(:dict.update key, fun, initial, data)
+  end
+
+  def empty(_) do
+    dict(:dict.new)
+  end
+
+  def to_list(dict(data)) do
+    :dict.to_list data
+  end
+end
+
+defimpl Enum.Iterator, for: HashDict do
+  def iterator({ HashDict, data }), do: :dict.to_list(data)
+  def count({ HashDict, data }), do: :dict.size(data)
+end
+
 defmodule HashDict do
  @moduledoc """
-  WARNING: this module is deprecated.
-
-  Use the `Map` module instead.
+  This module implements a dictionary based on hashing of the keys.
+  It is a simple wrapper around [Erlang's dict module](http://www.erlang.org/doc/man/dict.html)
+  and exposed via the `Dict` protocol.
  """

-  # TODO: Deprecate every function by 1.4
-
-  use Dict
-
-  @node_bitmap 0b111
-  @node_shift 3
-  @node_size 8
-  @node_template :erlang.make_tuple(@node_size, [])
-
-  @opaque t :: %__MODULE__{size: non_neg_integer, root: term}
-  @doc false
-  defstruct size: 0, root: @node_template
-
-  # Inline common instructions
-  @compile :inline_list_funcs
-  @compile {:inline, key_hash: 1, key_mask: 1, key_shift: 1}
-
-  @doc """
-  Creates a new empty dict.
-  """
-  @spec new :: Dict.t
-  def new do
-    %HashDict{}
-  end
-
-  def put(%HashDict{root: root, size: size}, key, value) do
-    {root, counter} = do_put(root, key, value, key_hash(key))
-    %HashDict{root: root, size: size + counter}
-  end
-
-  def update!(%HashDict{root: root, size: size} = dict, key, fun) when is_function(fun, 1) do
-    {root, counter} = do_update(root, key, fn -> raise KeyError, key: key, term: dict end,
-                                fun, key_hash(key))
-    %HashDict{root: root, size: size + counter}
-  end
-
-  def update(%HashDict{root: root, size: size}, key, initial, fun) when is_function(fun, 1) do
-    {root, counter} = do_update(root, key, fn -> initial end, fun, key_hash(key))
-    %HashDict{root: root, size: size + counter}
-  end
-
-  def fetch(%HashDict{root: root}, key) do
-    do_fetch(root, key, key_hash(key))
-  end
-
-  def delete(dict, key) do
-    case dict_delete(dict, key) do
-      {dict, _value} -> dict
-      :error         -> dict
-    end
-  end
-
-  def pop(dict, key, default \\ nil) do
-    case dict_delete(dict, key) do
-      {dict, value} -> {value, dict}
-      :error        -> {default, dict}
-    end
-  end
-
-  def size(%HashDict{size: size}) do
-    size
-  end
-
-  @doc false
-  def reduce(%HashDict{root: root}, acc, fun) do
-    do_reduce(root, acc, fun, @node_size, fn
-      {:suspend, acc} -> {:suspended, acc, &{:done, elem(&1, 1)}}
-      {:halt, acc}    -> {:halted, acc}
-      {:cont, acc}    -> {:done, acc}
-    end)
-  end
-
-  ## General helpers
-
-  @doc false
-  def dict_delete(%HashDict{root: root, size: size}, key) do
-    case do_delete(root, key, key_hash(key)) do
-      {root, value} -> {%HashDict{root: root, size: size - 1}, value}
-      :error        -> :error
-    end
-  end
-
-  ## Dict manipulation
-
-  defp do_fetch(node, key, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [^key | v]   -> {:ok, v}
-      {^key, v, _} -> {:ok, v}
-      {_, _, n}    -> do_fetch(n, key, key_shift(hash))
-      _            -> :error
-    end
-  end
-
-  defp do_put(node, key, value, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [] ->
-        {put_elem(node, index, [key | value]), 1}
-      [^key | _] ->
-        {put_elem(node, index, [key | value]), 0}
-      [k | v] ->
-        n = put_elem(@node_template, key_mask(key_shift(hash)), [key | value])
-        {put_elem(node, index, {k, v, n}), 1}
-      {^key, _, n} ->
-        {put_elem(node, index, {key, value, n}), 0}
-      {k, v, n} ->
-        {n, counter} = do_put(n, key, value, key_shift(hash))
-        {put_elem(node, index, {k, v, n}), counter}
-    end
-  end
-
-  defp do_update(node, key, initial, fun, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [] ->
-        {put_elem(node, index, [key | initial.()]), 1}
-      [^key | value] ->
-        {put_elem(node, index, [key | fun.(value)]), 0}
-      [k | v] ->
-        n = put_elem(@node_template, key_mask(key_shift(hash)), [key | initial.()])
-        {put_elem(node, index, {k, v, n}), 1}
-      {^key, value, n} ->
-        {put_elem(node, index, {key, fun.(value), n}), 0}
-      {k, v, n} ->
-        {n, counter} = do_update(n, key, initial, fun, key_shift(hash))
-        {put_elem(node, index, {k, v, n}), counter}
-    end
-  end
-
-  defp do_delete(node, key, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [] ->
-        :error
-      [^key | value] ->
-        {put_elem(node, index, []), value}
-      [_ | _] ->
-        :error
-      {^key, value, n} ->
-        {put_elem(node, index, do_compact_node(n)), value}
-      {k, v, n} ->
-        case do_delete(n, key, key_shift(hash)) do
-          {@node_template, value} ->
-            {put_elem(node, index, [k | v]), value}
-          {n, value} ->
-            {put_elem(node, index, {k, v, n}), value}
-          :error ->
-            :error
-        end
-    end
-  end
-
-  Enum.each 0..(@node_size - 1), fn index ->
-    defp do_compact_node(node) when elem(node, unquote(index)) != [] do
-      case elem(node, unquote(index)) do
-        [k | v] ->
-          case put_elem(node, unquote(index), []) do
-            @node_template -> [k | v]
-            n -> {k, v, n}
-          end
-        {k, v, n} ->
-          {k, v, put_elem(node, unquote(index), do_compact_node(n))}
-      end
-    end
-  end
-
-  ## Dict reduce
-
-  defp do_reduce_each(_node, {:halt, acc}, _fun, _next) do
-    {:halted, acc}
-  end
-
-  defp do_reduce_each(node, {:suspend, acc}, fun, next) do
-    {:suspended, acc, &do_reduce_each(node, &1, fun, next)}
-  end
-
-  defp do_reduce_each([], acc, _fun, next) do
-    next.(acc)
-  end
-
-  defp do_reduce_each([k | v], {:cont, acc}, fun, next) do
-    next.(fun.({k, v}, acc))
-  end
-
-  defp do_reduce_each({k, v, n}, {:cont, acc}, fun, next) do
-    do_reduce(n, fun.({k, v}, acc), fun, @node_size, next)
-  end
-
-  defp do_reduce(node, acc, fun, count, next) when count > 0 do
-    do_reduce_each(:erlang.element(count, node), acc, fun, &do_reduce(node, &1, fun, count - 1, next))
-  end
-
-  defp do_reduce(_node, acc, _fun, 0, next) do
-    next.(acc)
-  end
-
-  ## Key operations
-
-  import Bitwise
-
-  defp key_hash(key) do
-    :erlang.phash2(key)
-  end
-
-  defp key_mask(hash) do
-    hash &&& @node_bitmap
-  end
-
-  defp key_shift(hash) do
-    hash >>> @node_shift
-  end
-end
-
-defimpl Enumerable, for: HashDict do
-  def reduce(dict, acc, fun),  do: HashDict.reduce(dict, acc, fun)
-  def member?(dict, {k, v}), do: {:ok, match?({:ok, ^v}, HashDict.fetch(dict, k))}
-  def member?(_dict, _),       do: {:ok, false}
-  def count(dict),             do: {:ok, HashDict.size(dict)}
-end
-
-defimpl Collectable, for: HashDict do
-  def into(original) do
-    {original, fn
-      dict, {:cont, {k, v}} -> HashDict.put(dict, k, v)
-      dict, :done -> dict
-      _, :halt -> :ok
-    end}
-  end
-end
-
-defimpl Inspect, for: HashDict do
-  import Inspect.Algebra
-
-  def inspect(dict, opts) do
-    concat ["#HashDict<", Inspect.List.inspect(HashDict.to_list(dict), opts), ">"]
-  end
+  use Dict.Common, Dict.HashDict
 end
@@ -1,259 +0,0 @@
-defmodule HashSet do
-  @moduledoc """
-  WARNING: this module is deprecated.
-
-  Use the `MapSet` module instead.
-  """
-
-  # TODO: Deprecate every function by 1.4
-
-  @node_bitmap 0b111
-  @node_shift 3
-  @node_size 8
-  @node_template :erlang.make_tuple(@node_size, [])
-
-  @opaque t :: %__MODULE__{size: non_neg_integer, root: term}
-  @doc false
-  defstruct size: 0, root: @node_template
-
-  # Inline common instructions
-  @compile :inline_list_funcs
-  @compile {:inline, key_hash: 1, key_mask: 1, key_shift: 1}
-
-  @spec new :: Set.t
-  def new do
-    %HashSet{}
-  end
-
-  def union(%HashSet{size: size1} = set1, %HashSet{size: size2} = set2) when size1 <= size2 do
-    set_fold set1, set2, fn v, acc -> put(acc, v) end
-  end
-
-  def union(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold set2, set1, fn v, acc -> put(acc, v) end
-  end
-
-  def intersection(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold set1, %HashSet{}, fn v, acc ->
-      if member?(set2, v), do: put(acc, v), else: acc
-    end
-  end
-
-  def difference(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold set2, set1, fn v, acc -> delete(acc, v) end
-  end
-
-  def to_list(set) do
-    set_fold(set, [], &[&1 | &2]) |> :lists.reverse
-  end
-
-  def equal?(%HashSet{size: size1} = set1, %HashSet{size: size2} = set2) do
-    case size1 do
-      ^size2 -> subset?(set1, set2)
-      _      -> false
-    end
-  end
-
-  def subset?(%HashSet{} = set1, %HashSet{} = set2) do
-    reduce(set1, {:cont, true}, fn member, acc ->
-      case member?(set2, member) do
-        true -> {:cont, acc}
-        _    -> {:halt, false}
-      end
-    end) |> elem(1)
-  end
-
-  def disjoint?(%HashSet{} = set1, %HashSet{} = set2) do
-    reduce(set2, {:cont, true}, fn member, acc ->
-      case member?(set1, member) do
-        false -> {:cont, acc}
-        _     -> {:halt, false}
-      end
-    end) |> elem(1)
-  end
-
-  def member?(%HashSet{root: root}, term) do
-    do_member?(root, term, key_hash(term))
-  end
-
-  def put(%HashSet{root: root, size: size}, term) do
-    {root, counter} = do_put(root, term, key_hash(term))
-    %HashSet{root: root, size: size + counter}
-  end
-
-  def delete(%HashSet{root: root, size: size} = set, term) do
-    case do_delete(root, term, key_hash(term)) do
-      {:ok, root} -> %HashSet{root: root, size: size - 1}
-      :error      -> set
-    end
-  end
-
-  @doc false
-  def reduce(%HashSet{root: root}, acc, fun) do
-    do_reduce(root, acc, fun, @node_size, fn
-      {:suspend, acc} -> {:suspended, acc, &{:done, elem(&1, 1)}}
-      {:halt, acc}    -> {:halted, acc}
-      {:cont, acc}    -> {:done, acc}
-    end)
-  end
-
-  def size(%HashSet{size: size}) do
-    size
-  end
-
-  ## Set helpers
-
-  defp set_fold(%HashSet{root: root}, acc, fun) do
-    do_fold(root, acc, fun, @node_size)
-  end
-
-  ## Set manipulation
-
-  defp do_member?(node, term, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      []          -> false
-      [^term | _] -> true
-      [_]         -> false
-      [_ | n]     -> do_member?(n, term, key_shift(hash))
-    end
-  end
-
-  defp do_put(node, term, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [] ->
-        {put_elem(node, index, [term]), 1}
-      [^term | _] ->
-        {node, 0}
-      [t] ->
-        n = put_elem(@node_template, key_mask(key_shift(hash)), [term])
-        {put_elem(node, index, [t | n]), 1}
-      [t | n] ->
-        {n, counter} = do_put(n, term, key_shift(hash))
-        {put_elem(node, index, [t | n]), counter}
-    end
-  end
-
-  defp do_delete(node, term, hash) do
-    index = key_mask(hash)
-    case elem(node, index) do
-      [] ->
-        :error
-      [^term] ->
-        {:ok, put_elem(node, index, [])}
-      [_] ->
-        :error
-      [^term | n] ->
-        {:ok, put_elem(node, index, do_compact_node(n))}
-      [t | n] ->
-        case do_delete(n, term, key_shift(hash)) do
-          {:ok, @node_template} ->
-            {:ok, put_elem(node, index, [t])}
-          {:ok, n} ->
-            {:ok, put_elem(node, index, [t | n])}
-          :error ->
-            :error
-        end
-    end
-  end
-
-  Enum.each 0..(@node_size - 1), fn index ->
-    defp do_compact_node(node) when elem(node, unquote(index)) != [] do
-      case elem(node, unquote(index)) do
-        [t] ->
-          case put_elem(node, unquote(index), []) do
-            @node_template -> [t]
-            n -> [t | n]
-          end
-        [t | n] ->
-          [t | put_elem(node, unquote(index), do_compact_node(n))]
-      end
-    end
-  end
-
-  ## Set fold
-
-  defp do_fold_each([], acc, _fun),     do: acc
-  defp do_fold_each([t], acc, fun),     do: fun.(t, acc)
-  defp do_fold_each([t | n], acc, fun), do: do_fold(n, fun.(t, acc), fun, @node_size)
-
-  defp do_fold(node, acc, fun, count) when count > 0 do
-    acc = do_fold_each(:erlang.element(count, node), acc, fun)
-    do_fold(node, acc, fun, count - 1)
-  end
-
-  defp do_fold(_node, acc, _fun, 0) do
-    acc
-  end
-
-  ## Set reduce
-
-  defp do_reduce_each(_node, {:halt, acc}, _fun, _next) do
-    {:halted, acc}
-  end
-
-  defp do_reduce_each(node, {:suspend, acc}, fun, next) do
-    {:suspended, acc, &do_reduce_each(node, &1, fun, next)}
-  end
-
-  defp do_reduce_each([], acc, _fun, next) do
-    next.(acc)
-  end
-
-  defp do_reduce_each([t], {:cont, acc}, fun, next) do
-    next.(fun.(t, acc))
-  end
-
-  defp do_reduce_each([t | n], {:cont, acc}, fun, next) do
-    do_reduce(n, fun.(t, acc), fun, @node_size, next)
-  end
-
-  defp do_reduce(node, acc, fun, count, next) when count > 0 do
-    do_reduce_each(:erlang.element(count, node), acc, fun, &do_reduce(node, &1, fun, count - 1, next))
-  end
-
-  defp do_reduce(_node, acc, _fun, 0, next) do
-    next.(acc)
-  end
-
-  ## Key operations
-
-  import Bitwise
-
-  defp key_hash(key) do
-    :erlang.phash2(key)
-  end
-
-  defp key_mask(hash) do
-    hash &&& @node_bitmap
-  end
-
-  defp key_shift(hash) do
-    hash >>> @node_shift
-  end
-end
-
-defimpl Enumerable, for: HashSet do
-  def reduce(set, acc, fun), do: HashSet.reduce(set, acc, fun)
-  def member?(set, v),       do: {:ok, HashSet.member?(set, v)}
-  def count(set),            do: {:ok, HashSet.size(set)}
-end
-
-defimpl Collectable, for: HashSet do
-  def into(original) do
-    {original, fn
-      set, {:cont, x} -> HashSet.put(set, x)
-      set, :done -> set
-      _, :halt -> :ok
-    end}
-  end
-end
-
-defimpl Inspect, for: HashSet do
-  import Inspect.Algebra
-
-  def inspect(set, opts) do
-    concat ["#HashSet<", Inspect.List.inspect(HashSet.to_list(set), opts), ">"]
-  end
-end
@@ -0,0 +1,212 @@
+defrecord IEx.Config, io: nil, binding: nil, cache: '', counter: 1, scope: nil, result: nil
+
+defmodule IEx do
+  @moduledoc """
+  This module implements interactive Elixir. It provides a main
+  function, `start` which will either delegate to `tty` or `simple`.
+  The former is meant for systems where tty is available and relies
+  on it in order to work properly. This makes all control commands
+  available in tty available to the developer.
+
+  In case `tty` is not available (for example, Windows), a
+  developer may invoke `simple` which starts a stripped
+  down version.
+  """
+
+  import Exception, only: [format_stacktrace: 1]
+
+  @doc """
+  Interface to start IEx from CLI.
+  """
+  def cli do
+    run([remsh: get_remsh(:init.get_plain_arguments)])
+  end
+
+  defp get_remsh(['--remsh',h|_]), do: list_to_binary(h)
+  defp get_remsh([_|t]), do: get_remsh(t)
+  defp get_remsh([]),    do: nil
+
+  @doc """
+  Runs IEx checking if tty is available or not.
+  If so, invoke tty, otherwise go with the simple iex.
+  """
+  def run(opts // []) when is_list(opts) do
+    case :os.type do
+      { :unix, _ } -> tty(opts)
+      _            -> simple(opts)
+    end
+  end
+
+  @doc """
+  Starts IEx using a tty server.
+  """
+  def tty(opts // []) when is_list(opts) do
+    config = boot_config(opts)
+
+    remote =
+      if remsh = opts[:remsh] do
+        if node() == :nonode@nohost do
+          raise ArgumentError, message: "In order to use --remsh, you need to name the node"
+        end
+        if is_atom(remsh), do: remsh, else: binary_to_atom(remsh)
+      end
+
+    function = fn ->
+      # We are inside the new tty and in a new process,
+      # reattach it the error logger.
+      attach_error_logger
+
+      start config
+    end
+
+    # Dettach the error logger because we are going to unregister
+    # the user process and start a new tty which will get control
+    # over the standardio. Dettaching it here allows us to get rid
+    # of warnings. We reattach it again when we get the new tty.
+    dettach_error_logger
+
+    # Unregister the user process, user_drv command below
+    # will register the new one.
+    unregister_user_process
+
+    # Close the default io port, user_drv start command below
+    # will take control over the io.
+    close_io_port
+
+    args =
+      if remote do
+        { remote, :erlang, :apply, [function, []] }
+      else
+        { :erlang, :apply, [function, []] }
+      end
+
+    Erlang.user_drv.start([:"tty_sl -c -e", args])
+  end
+
+  @doc """
+  Starts IEx simply using the current stdio.
+  """
+  def simple(opts // []) when is_list(opts) do
+    start boot_config(opts)
+  end
+
+  # This is a callback invoked by Erlang shell utilities.
+  @doc false
+  def start(config // nil) do
+    spawn fn ->
+      config = config || boot_config([])
+      gl = :erlang.group_leader
+      glnode = node gl
+      if glnode != node do
+        ensure_module_exists glnode, IEx.Remsh
+        expand_fun = IEx.Remsh.expand node
+      else
+        expand_fun = IEx.Autocomplete.expand &1
+      end
+      :io.setopts gl, [expand_fun: expand_fun]
+      start_loop(config)
+    end
+  end
+
+  ## Boot Helpers
+
+  defp boot_config(opts) do
+    IO.puts "Interactive Elixir (#{System.version}) - press Ctrl+C to exit"
+
+    scope  = Erlang.elixir.scope_for_eval(
+      file: 'iex',
+      delegate_locals_to: IEx.Helpers
+    )
+
+    IEx.Config[
+      io: opts[:io] || IEx.UnicodeIO,
+      binding: opts[:binding] || [],
+      scope: scope
+    ]
+  end
+
+  defp dettach_error_logger do
+    :error_logger.delete_report_handler(:error_logger_tty_h)
+  end
+
+  defp attach_error_logger do
+    :error_logger.add_report_handler(:error_logger_tty_h)
+  end
+
+  defp unregister_user_process do
+    if is_pid(Process.whereis(:user)), do: Process.unregister :user
+  end
+
+  defp close_io_port do
+    if port = Enum.find(Port.list, io_port?(&1)) do
+      Port.close(port)
+    end
+  end
+
+  defp io_port?(port) do
+    Port.info(port, :name) == {:name,'0/1'} && port
+  end
+
+  ## Loop helpers
+
+  defp start_loop(config) do
+    Process.put :iex_history, []
+    { _, _, scope } = Erlang.elixir.eval('import IEx.Helpers', [], 0, config.scope)
+    do_loop(config.scope(scope))
+  end
+
+  defp do_loop(config) do
+    io = config.io
+
+    counter = config.counter
+    cache   = config.cache
+    code    = cache ++ io.get(config)
+
+    new_config =
+      try do
+        { result, new_binding, scope } =
+          Erlang.elixir.eval(code, config.binding, counter, config.scope)
+
+        io.put result
+
+        config = config.result(result)
+        update_history(config.cache(code).scope(nil))
+        config.increment_counter.cache('').binding(new_binding).scope(scope)
+      rescue
+        TokenMissingError ->
+          config.cache(code)
+        exception ->
+          stacktrace = System.stacktrace
+          io.error "** (#{inspect exception.__record__(:name)}) #{exception.message}"
+          print_stacktrace io, stacktrace
+          config.cache('')
+      catch
+        kind, error ->
+          stacktrace = System.stacktrace
+          io.error "** (#{kind}) #{inspect(error)}"
+          print_stacktrace io, stacktrace
+          config.cache('')
+      end
+
+    do_loop(new_config)
+  end
+
+  defp update_history(config) do
+    current = Process.get :iex_history
+    Process.put :iex_history, [config|current]
+  end
+
+  defp print_stacktrace(io, stacktrace) do
+    Enum.each stacktrace, fn s -> io.error "    #{format_stacktrace(s)}" end
+  end
+
+  ## Code injection helper
+
+  defp ensure_module_exists(node, mod) do
+    unless :rpc.call node, :code, :is_loaded, [mod] do
+      {m,b,f} = :code.get_object_code mod
+      {:module, mod} = :rpc.call node, :code, :load_binary, [m,f,b]
+    end
+  end
+end
+
@@ -0,0 +1,266 @@
+defmodule IEx.Autocomplete do
+  @moduledoc """
+  Autocompletion for the Elixir shell.
+  """
+
+  defrecord Mod, name: nil, type: nil
+  defrecord Fun, name: nil, arities: []
+
+  defprotocol Entry do
+    @moduledoc false
+    def to_entries(entry)
+    def to_hint(entry, hint)
+  end
+
+  defimpl Entry, for: Mod do
+    def to_entries(mod) do
+      [mod.name]
+    end
+
+    def to_hint(Mod[name: name], hint) do
+      :lists.nthtail(length(hint), name) ++ '.'
+    end
+  end
+
+  defimpl Entry, for: Fun do
+    def to_entries(fun) do
+      lc a inlist fun.arities, do: '#{fun.name}/#{a}'
+    end
+
+    def to_hint(Fun[name: name], hint) do
+      :lists.nthtail(length(hint), name)
+    end
+  end
+
+  def expand([]) do
+    funs = module_funs(IEx.Helpers) ++ module_funs(Kernel)
+    mods = [Mod[name: 'Elixir', type: :elixir], Mod[name: 'Erlang', type: :elixir]]
+    format_expansion mods ++ funs
+  end
+
+  def expand([h|t]=expr) do
+    cond do
+      h === ?. ->
+        expand_dot reduce(t)
+      h === ?: ->
+        expand_erlang_modules
+      (h in ?a..?z) or (h in ?A..?Z) or h === ?_ ->
+        expand_expr reduce(expr)
+      h in '(+[' ->
+        expand ''
+      true ->
+        no_match
+    end
+  end
+
+  defp expand_dot(expr) do
+    case Code.string_to_ast expr do
+      {:ok, atom} when is_atom(atom) ->
+        expand_module_funs atom
+      {:ok, {:__aliases__,_,[:Erlang]}} ->
+        expand_erlang_modules
+      {:ok, {:__aliases__,_,list}} ->
+        expand_elixir_modules list
+      {:ok, {{:.,_,[{:__aliases__,_,[:Erlang]},mod]},_,[]}} when is_atom(mod) ->
+        expand_module_funs mod
+      _ ->
+        no_match
+    end
+  end
+
+  defp expand_expr(expr) do
+    case Code.string_to_ast expr do
+      {:ok, atom} when is_atom(atom) ->
+        expand_erlang_modules atom_to_list(atom)
+      {:ok, { atom, _, nil }} when is_atom(atom) ->
+        expand_module_funs Kernel, atom_to_list(atom)
+      {:ok, {:__aliases__,_,[root]}} ->
+        expand_elixir_modules [], atom_to_list(root)
+      {:ok, {:__aliases__,_,list}} ->
+        hint = atom_to_list(List.last(list))
+        list = :lists.sublist(list, length(list)-1)
+        expand_elixir_modules list, hint
+      {:ok, {{:., _, [mod,fun]},_,[]}} when is_atom(fun) ->
+        expand_call mod, atom_to_list(fun)
+      _ -> no_match
+    end
+  end
+
+  defp reduce(expr) do
+    last_token(List.reverse(expr), [' ', '(', '[', '+', '-'])
+  end
+
+  defp last_token(s, []) do
+    s
+  end
+
+  defp last_token(s, [h|t]) do
+    last_token(List.last(:string.tokens(s, h)), t)
+  end
+
+  defp no_match, do: { :no, '', [] }
+
+  ## Formatting
+
+  defp format_expansion(list, hint // '')
+
+  defp format_expansion([], _) do
+    no_match
+  end
+
+  defp format_expansion([uniq], hint) do
+    { :yes, Entry.to_hint(uniq, hint), [] }
+  end
+
+  defp format_expansion([first|_]=entries, hint) do
+    binary = Enum.map entries, fn e -> list_to_binary(e.name) end
+    length = length hint
+    prefix = :binary.longest_common_prefix(binary)
+    if prefix == 0 or (prefix == length) do
+      {:yes, '',
+         Enum.reduce entries, [], fn e, acc -> Entry.to_entries(e) ++ acc end }
+    else
+      {:yes, :lists.sublist(first.name, 1 + length, prefix-length), [] }
+    end
+  end
+
+  ## Root Modules
+
+  defp root_modules do
+    Enum.reduce :code.all_loaded, [], fn {m,_}, acc ->
+      mod = atom_to_list(m)
+      case mod do
+        'Elixir' ++ _ ->
+          tokens = :string.tokens(mod, '-')
+          if length(tokens) === 2 do
+            [Mod.new(name: List.last(tokens), type: :elixir)|acc]
+          else
+            acc
+          end
+        _ ->
+          [Mod.new(name: mod, type: :erlang)|acc]
+      end
+    end
+  end
+
+  ## Expand calls
+
+  # :atom.fun
+  defp expand_call(mod, hint) when is_atom(mod) do
+    expand_module_funs mod, hint
+  end
+
+  # Erlang.mod.fun
+  defp expand_call({ { :., _, [{ :__aliases__, _, [:Erlang] }, mod] }, _, [] }, hint) when is_atom(mod) do
+    expand_module_funs mod, hint
+  end
+
+  # Erlang.mod
+  defp expand_call({ :__aliases__, _, [:Erlang] }, hint) do
+    expand_erlang_modules hint
+  end
+
+  # Elixir.fun
+  defp expand_call({ :__aliases__, _, list }, hint) do
+    expand_module_funs Module.concat(list), hint
+  end
+
+  defp expand_call(_, _) do
+    no_match
+  end
+
+  ## Erlang modules
+
+  defp expand_erlang_modules(hint // '') do
+    format_expansion match_erlang_modules(hint), hint
+  end
+
+  defp match_erlang_modules('') do
+    Enum.filter root_modules, fn m -> m.type === :erlang end
+  end
+
+  defp match_erlang_modules(hint) do
+    Enum.filter root_modules, fn m -> :lists.prefix(hint, m.name) end
+  end
+
+  ## Elixir modules
+
+  defp expand_elixir_modules(list, hint // '') do
+    mod = Module.concat(list)
+    format_expansion elixir_submodules(mod, hint, list == []) ++ module_funs(mod, hint), hint
+  end
+
+  defp elixir_submodules(mod, hint, root) do
+    modname = atom_to_list(mod)
+    depth   = length(:string.tokens(modname, '-')) + 1
+    base    = modname ++ [?-|hint]
+
+    Enum.reduce modules_as_lists(root), [], fn(m, acc) ->
+      if :lists.prefix(base, m) do
+        tokens = :string.tokens(m, '-')
+        if length(tokens) == depth do
+          name = List.last(tokens)
+          [Mod.new(type: :elixir, name: name)|acc]
+        else
+          acc
+        end
+      else
+        acc
+      end
+    end
+  end
+
+  defp modules_as_lists(true) do
+    ['Elixir-Elixir', 'Elixir-Erlang'] ++ modules_as_lists(false)
+  end
+
+  defp modules_as_lists(false) do
+    Enum.map(:code.all_loaded, fn({ m, _ }) -> atom_to_list(m) end)
+  end
+
+  ## Functions
+
+  defp expand_module_funs(mod, hint // '') do
+    format_expansion module_funs(mod, hint), hint
+  end
+
+  defp module_funs(mod, hint // '') do
+    case ensure_loaded(mod) do
+      { :module, _ } ->
+        falist = get_funs(mod)
+
+        list = Enum.reduce falist, [], fn {f,a}, acc ->
+          case :lists.keyfind(f, 1, acc) do
+            {f,aa} -> :lists.keyreplace(f, 1, acc, {f, [a|aa]})
+            false  -> [{f, [a]}|acc]
+          end
+        end
+
+        lc {fun, arities} inlist list, name = atom_to_list(fun), is_prefix?(hint, name) do
+          Fun[name: name, arities: arities]
+        end
+      _ ->
+        []
+    end
+  end
+
+  ## Generic Helpers
+
+  defp get_funs(mod) do
+    if function_exported?(mod, :__info__, 1) do
+      if docs = mod.__info__(:docs) do
+        lc { pair, _line, _kind, _sign, doc } inlist docs, doc != false, do: pair
+      else
+        (mod.__info__(:functions) -- [__info__: 1]) ++ mod.__info__(:macros)
+      end
+    else
+      mod.module_info(:exports)
+    end
+  end
+
+  defp is_prefix?('', _),      do: true
+  defp is_prefix?(hint, name), do: :lists.prefix(hint, name)
+
+  defp ensure_loaded(Elixir), do: { :error, :nofile }
+  defp ensure_loaded(mod),    do: Code.ensure_loaded(mod)
+end
@@ -0,0 +1,244 @@
+defmodule IEx.Helpers do
+  @moduledoc """
+  A bunch of helpers available in IEx.
+
+  * `c` - compiles a file in the given path
+  * `d` - prints documentation
+  * `h` - prints history
+  * `m` - prints loaded modules
+  * `r` - recompiles and reloads the given module's source file
+  * `v` - retrieves nth value from console
+
+  Documentation for functions in this module can be consulted
+  directly from the command line, as an example, try:
+
+    d(:c, 1)
+
+  """
+
+  @doc """
+  Expects a list of files to compile and a path
+  to write their object code to. It returns the name
+  of the compiled modules.
+
+  ## Examples
+
+      c ["foo.ex"], "ebin"
+      #=> Foo
+
+  """
+  def c(files, path // ".") do
+    tuples = Kernel.ParallelCompiler.files_to_path List.wrap(files), path
+    Enum.map tuples, elem(&1, 1)
+  end
+
+  @doc """
+  Returns the name and module of all modules loaded.
+  """
+  def m do
+    all    = Enum.map :code.all_loaded, fn { mod, file } -> { inspect(mod), file } end
+    sorted = List.sort(all)
+    size   = Enum.reduce sorted, 0, fn({ mod, _ }, acc) -> max(byte_size(mod), acc) end
+    format = "~-#{size}s ~s~n"
+
+    Enum.each sorted, fn({ mod, file }) ->
+      :io.format(format, [mod, file])
+    end
+  end
+
+  @doc """
+  Prints commands history and their result.
+  """
+  def h do
+    history = List.reverse(Process.get(:iex_history))
+    Enum.each(history, print_history(&1))
+  end
+
+  defp print_history(config) do
+    IO.puts "#{config.counter}: #{config.cache}#=> #{inspect config.result}\n"
+  end
+
+  @doc """
+  Shows the documentation for IEx.Helpers.
+  """
+  def d() do
+    d(IEx.Helpers, :all)
+  end
+
+  @doc """
+  Shows the documentation for the given module
+  or for the given function/arity pair.
+
+  ## Examples
+
+      d(Enum)
+      #=> Prints documentation for Enum
+
+  It also accepts functions in the format `fun/arity`
+  and `module.fun/arity`, for example:
+
+      d receive/1
+      d Enum.all?/2
+
+  """
+  defmacro d({ :/, _, [{ fun, _, nil }, arity] }) do
+    quote do
+      d(unquote(fun), unquote(arity))
+    end
+  end
+
+  defmacro d({ :/, _, [{ { :., _, [mod, fun] }, _, [] }, arity] }) do
+    quote do
+      d(unquote(mod), unquote(fun), unquote(arity))
+    end
+  end
+
+  defmacro d(other) do
+    quote do
+      d(unquote(other), :all)
+    end
+  end
+
+  @doc """
+  Prints the documentation for the given function and arity.
+
+  The function may either be a function defined inside `IEx.Helpers`
+  or in `Kernel`. To see functions from other module, use
+  `d/3` instead.
+
+  ## Examples
+
+      d(:d, 2)
+      #=> Prints documentation for this function
+
+  """
+  def d(:d, 1) do
+    d(__MODULE__, :d, 1)
+  end
+
+  def d(function, arity) when is_atom(function) and is_integer(arity) do
+    if function_exported?(__MODULE__, function, arity) do
+      d(__MODULE__, function, arity)
+    else
+      d(Kernel, function, arity)
+    end
+  end
+
+  def d(module, :all) when is_atom(module) do
+    case Code.ensure_loaded(module) do
+      { :module, _ } ->
+        case module.__info__(:moduledoc) do
+          { _, binary } when is_binary(binary) ->
+            IO.puts "# #{inspect module}\n"
+            IO.write binary
+          { _, _ } ->
+            IO.puts "No docs for #{inspect module}"
+          _ ->
+            IO.puts "#{inspect module} was not compiled with docs"
+        end
+      { :error, reason } ->
+        IO.puts "Could not load module #{inspect module}: #{reason}"
+    end
+  end
+
+  @doc """
+  Shows the documentation for the `function/arity` in `module`.
+  """
+  def d(module, function, arity) when is_atom(module) and is_atom(function) and is_integer(arity) do
+    if docs = module.__info__(:docs) do
+      doc =
+        if tuple = List.keyfind(docs, { function, arity }, 1) do
+          print_signature(tuple)
+        end
+
+      if doc do
+        IO.write "\n" <> doc
+      else
+        IO.puts "No docs for #{function}/#{arity}"
+      end
+    else
+      IO.puts "#{inspect module} was not compiled with docs"
+    end
+  end
+
+  # Get the full signature from a function.
+  defp print_signature({ _info, _line, _kind, _args, false }) do
+    false
+  end
+
+  defp print_signature({ { name, _arity }, _line, kind, args, docs }) do
+    args = Enum.map_join(args, ", ", signature_arg(&1))
+    IO.puts "* #{kind} #{name}(#{args})"
+    docs
+  end
+
+  defp signature_arg({ ://, _, [left, right] }) do
+    signature_arg(left) <> " // " <> Macro.to_binary(right)
+  end
+
+  defp signature_arg({ var, _, _ }) do
+    atom_to_binary(var)
+  end
+
+  @doc """
+  Retrieves nth query's value from the history. Use negative
+  values to lookup query's value from latest to earliest.
+  For instance, v(-1) returns the latest result.
+  """
+  def v(n) when n < 0 do
+    history = Process.get(:iex_history)
+    Enum.nth!(history, abs(n)).result
+  end
+
+  def v(n) do
+    history = Process.get(:iex_history) /> List.reverse
+    Enum.nth!(history, n).result
+  end
+
+  @doc """
+  Reloads all modules that were already reloaded
+  at some point with `r/1`.
+  """
+  def r do
+    Enum.map iex_reloaded, r(&1)
+  end
+
+  @doc """
+  Recompiles and reloads the specified module's source file.
+
+  Please note that all the modules defined in the specified
+  files are recompiled and reloaded.
+  """
+  def r(module) do
+    if source = source(module) do
+      Process.put(:iex_reloaded, :ordsets.add_element(module, iex_reloaded))
+      { module, Code.load_file source }
+    else
+      :nosource
+    end
+  end
+
+  defp iex_reloaded do
+    Process.get(:iex_reloaded) || :ordsets.new
+  end
+
+  defp source(module) do
+    compile = module.module_info(:compile)
+
+    # Get the source of the compiled module. Due to a bug in Erlang
+    # R15 and before, we need to look for the source first in the
+    # options and then into the real source.
+    options =
+      case List.keyfind(compile, :options, 1) do
+        { :options, opts } -> opts
+        _ -> []
+      end
+
+    source = List.keyfind(options, :source, 1)  || List.keyfind(compile, :source, 1)
+
+    case source do
+      { :source, source } -> list_to_binary(source)
+      _ -> nil
+    end
+  end
+end
@@ -0,0 +1,24 @@
+defmodule IEx.Remsh do
+  @moduledoc """
+  Helper function injected into connecting remote nodes
+  to properly handle autocompletion. Elixir supports:
+
+  * remsh from an elixir node to an elixir node
+  * remsh from a plain erlang node to an elixir node (through the ^G menu)
+  * remsh from an elixir node to a plain erlang node (and get an erl shell there)
+
+  In order to get an Elixir shell from the ^G menu,
+  you need to use 'Elixir-IEx' as the shell name.
+
+  Connecting an Elixir shell to a remote node without
+  Elixir is **not** supported.
+  """
+  def expand(node) do
+    fn e ->
+      case :rpc.call node, Elixir.IEx.Autocomplete, :expand, [e] do
+        {:badrpc, _} -> {:no, '', []}
+        r -> r 
+      end
+    end
+  end
+end
@@ -0,0 +1,45 @@
+defmodule IEx.UnicodeIO do
+  @moduledoc """
+  This module implements the API used by IEX to
+  interact with the console. This API may change
+  in the future without warnings.
+  """
+
+  @doc """
+  Implements the get IO API used by IEx. It receives the
+  code cache, the instructions counter and needs to
+  return a list with the new characters inserted.
+  """
+  def get(config) do
+    prefix = case config.cache do
+      [] -> "iex"
+      _  -> "..."
+    end
+    prompt = case node do
+      :nonode@nohost ->
+        "#{prefix}(#{config.counter})> "
+      n ->
+        "#{prefix}(#{n})#{config.counter}> "
+    end
+    case IO.gets(prompt) do
+      { :error, _ } -> ''
+      data -> :unicode.characters_to_list(data)
+    end
+  end
+
+  @doc """
+  Implements the put IO API used by IEx. It receives the
+  result and prints it.
+  """
+  def put(result) do
+    IO.inspect result
+  end
+
+  @doc """
+  Implements the error IO API used by IEx. It prints error
+  messages.
+  """
+  def error(result) do
+    IO.puts result
+  end
+end
@@ -1,553 +0,0 @@
-import Kernel, except: [inspect: 1]
-import Inspect.Algebra
-
-defprotocol Inspect do
-  @moduledoc """
-  The `Inspect` protocol is responsible for converting any Elixir
-  data structure into an algebra document. This document is then
-  formatted, either in pretty printing format or a regular one.
-
-  The `inspect/2` function receives the entity to be inspected
-  followed by the inspecting options, represented by the struct
-  `Inspect.Opts`.
-
-  Inspection is done using the functions available in `Inspect.Algebra`.
-
-  ## Examples
-
-  Many times, inspecting a structure can be implemented in function
-  of existing entities. For example, here is `MapSet`'s `inspect`
-  implementation:
-
-      defimpl Inspect, for: MapSet do
-        import Inspect.Algebra
-
-        def inspect(dict, opts) do
-          concat ["#MapSet<", to_doc(MapSet.to_list(dict), opts), ">"]
-        end
-      end
-
-  The `concat/1` function comes from `Inspect.Algebra` and it
-  concatenates algebra documents together. In the example above,
-  it is concatenating the string `"MapSet<"` (all strings are
-  valid algebra documents that keep their formatting when pretty
-  printed), the document returned by `Inspect.Algebra.to_doc/2` and the
-  other string `">"`.
-
-  Since regular strings are valid entities in an algebra document,
-  an implementation of inspect may simply return a string,
-  although that will devoid it of any pretty-printing.
-
-  ## Error handling
-
-  In case there is an error while your structure is being inspected,
-  Elixir will raise an `ArgumentError` error and will automatically fall back
-  to a raw representation for printing the structure.
-
-  You can however access the underlying error by invoking the Inspect
-  implementation directly. For example, to test Inspect.MapSet above,
-  you can invoke it as:
-
-      Inspect.MapSet.inspect(MapSet.new, %Inspect.Opts{})
-
-  """
-
-  # Handle structs in Any
-  @fallback_to_any true
-
-  def inspect(term, opts)
-end
-
-defimpl Inspect, for: Atom do
-  require Macro
-
-  def inspect(atom, opts) do
-    color(inspect(atom), color_key(atom), opts)
-  end
-
-  defp color_key(atom) when is_boolean(atom), do: :boolean
-  defp color_key(nil), do: :nil
-  defp color_key(_), do: :atom
-
-  def inspect(false),  do: "false"
-  def inspect(true),   do: "true"
-  def inspect(nil),    do: "nil"
-  def inspect(:""),    do: ":\"\""
-
-  def inspect(atom) do
-    binary = Atom.to_string(atom)
-
-    cond do
-      valid_ref_identifier?(binary) ->
-        if only_elixir?(binary) do
-          binary
-        else
-          "Elixir." <> rest = binary
-          rest
-        end
-      valid_atom_identifier?(binary) ->
-        ":" <> binary
-      atom in [:%{}, :{}, :<<>>, :..., :%] ->
-        ":" <> binary
-      atom in Macro.binary_ops or atom in Macro.unary_ops ->
-        ":" <> binary
-      true ->
-        IO.iodata_to_binary [?:, ?", Inspect.BitString.escape(binary, ?"), ?"]
-    end
-  end
-
-  defp only_elixir?("Elixir." <> rest), do: only_elixir?(rest)
-  defp only_elixir?("Elixir"), do: true
-  defp only_elixir?(_), do: false
-
-  # Detect if atom is an atom alias (Elixir.Foo.Bar.Baz)
-
-  defp valid_ref_identifier?("Elixir" <> rest) do
-    valid_ref_piece?(rest)
-  end
-
-  defp valid_ref_identifier?(_), do: false
-
-  defp valid_ref_piece?(<<?., h, t::binary>>) when h in ?A..?Z do
-    valid_ref_piece? valid_identifier?(t)
-  end
-
-  defp valid_ref_piece?(<<>>), do: true
-  defp valid_ref_piece?(_),    do: false
-
-  # Detect if atom
-
-  defp valid_atom_identifier?(<<h, t::binary>>) when h in ?a..?z or h in ?A..?Z or h == ?_ do
-    valid_atom_piece?(t)
-  end
-
-  defp valid_atom_identifier?(_), do: false
-
-  defp valid_atom_piece?(t) do
-    case valid_identifier?(t) do
-      <<>>              -> true
-      <<??>>            -> true
-      <<?!>>            -> true
-      <<?@, t::binary>> -> valid_atom_piece?(t)
-      _                 -> false
-    end
-  end
-
-  defp valid_identifier?(<<h, t::binary>>)
-      when h in ?a..?z
-      when h in ?A..?Z
-      when h in ?0..?9
-      when h == ?_ do
-    valid_identifier? t
-  end
-
-  defp valid_identifier?(other), do: other
-end
-
-defimpl Inspect, for: BitString do
-  def inspect(term, %Inspect.Opts{binaries: bins, base: base} = opts) when is_binary(term) do
-    if base == :decimal and (bins == :as_strings or (bins == :infer and String.printable?(term))) do
-      inspected = IO.iodata_to_binary([?", escape(term, ?"), ?"])
-      color(inspected, :string, opts)
-    else
-      inspect_bitstring(term, opts)
-    end
-  end
-
-  def inspect(term, opts) do
-    inspect_bitstring(term, opts)
-  end
-
-  ## Escaping
-
-  @doc false
-  def escape(other, char) do
-    escape(other, char, [])
-  end
-
-  defp escape(<<char, t::binary>>, char, acc) do
-    escape(t, char, [acc | [?\\, char]])
-  end
-  defp escape(<<?#, ?{, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\\#{'])
-  end
-  defp escape(<<?\a, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\a'])
-  end
-  defp escape(<<?\b, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\b'])
-  end
-  defp escape(<<?\d, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\d'])
-  end
-  defp escape(<<?\e, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\e'])
-  end
-  defp escape(<<?\f, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\f'])
-  end
-  defp escape(<<?\n, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\n'])
-  end
-  defp escape(<<?\r, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\r'])
-  end
-  defp escape(<<?\\, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\\\'])
-  end
-  defp escape(<<?\t, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\t'])
-  end
-  defp escape(<<?\v, t::binary>>, char, acc) do
-    escape(t, char, [acc | '\\v'])
-  end
-  defp escape(<<h::utf8, t::binary>>, char, acc)
-       when h in 0x20..0x7E
-       when h in 0xA0..0xD7FF
-       when h in 0xE000..0xFFFD
-       when h in 0x10000..0x10FFFF do
-    escape(t, char, [acc | <<h::utf8>>])
-  end
-  defp escape(<<h, t::binary>>, char, acc) do
-    escape(t, char, [acc | escape_char(h)])
-  end
-  defp escape(<<>>, _char, acc), do: acc
-
-  @doc false
-  # Also used by Regex
-  def escape_char(0) do
-    '\\0'
-  end
-
-  def escape_char(char) when char < 0x100 do
-    <<a::4, b::4>> = <<char::8>>
-    ['\\x', to_hex(a), to_hex(b)]
-  end
-
-  def escape_char(char) when char < 0x10000 do
-    <<a::4, b::4, c::4, d::4>> = <<char::16>>
-    ['\\x{', to_hex(a), to_hex(b), to_hex(c), to_hex(d), ?}]
-  end
-
-  def escape_char(char) when char < 0x1000000 do
-    <<a::4, b::4, c::4, d::4, e::4, f::4>> = <<char::24>>
-    ['\\x{', to_hex(a), to_hex(b), to_hex(c),
-             to_hex(d), to_hex(e), to_hex(f), ?}]
-  end
-
-  defp to_hex(c) when c in 0..9, do: ?0+c
-  defp to_hex(c) when c in 10..15, do: ?A+c-10
-
-  ## Bitstrings
-
-  defp inspect_bitstring("", opts) do
-    color("<<>>", :binary, opts)
-  end
-
-  defp inspect_bitstring(bitstring, opts) do
-    left = color("<<", :binary, opts)
-    right = color(">>", :binary, opts)
-    nest surround(left, each_bit(bitstring, opts.limit, opts), right), 1
-  end
-
-  defp each_bit(_, 0, _) do
-    "..."
-  end
-
-  defp each_bit(<<>>, _counter, _opts) do
-    :doc_nil
-  end
-
-  defp each_bit(<<h::8>>, _counter, opts) do
-    Inspect.Integer.inspect(h, opts)
-  end
-
-  defp each_bit(<<h, t::bitstring>>, counter, opts) do
-    glue(concat(Inspect.Integer.inspect(h, opts), ","),
-         each_bit(t, decrement(counter), opts))
-  end
-
-  defp each_bit(bitstring, _counter, opts) do
-    size = bit_size(bitstring)
-    <<h::size(size)>> = bitstring
-    Inspect.Integer.inspect(h, opts) <> "::size(" <> Integer.to_string(size) <> ")"
-  end
-
-  defp decrement(:infinity), do: :infinity
-  defp decrement(counter),   do: counter - 1
-end
-
-defimpl Inspect, for: List do
-  def inspect([], opts) do
-    color("[]", :list, opts)
-  end
-
-  # TODO: Deprecate :char_lists and :as_char_lists keys in v1.5
-  def inspect(term, %Inspect.Opts{charlists: lists, char_lists: lists_deprecated} = opts) do
-    lists =
-      if lists == :infer and lists_deprecated != :infer do
-        case lists_deprecated do
-          :as_char_lists ->
-            :as_charlists
-          _ ->
-            lists_deprecated
-        end
-      else
-        lists
-      end
-
-    open = color("[", :list, opts)
-    sep = color(",", :list, opts)
-    close = color("]", :list, opts)
-
-    cond do
-      lists == :as_charlists or (lists == :infer and printable?(term)) ->
-        IO.iodata_to_binary [?', Inspect.BitString.escape(IO.chardata_to_string(term), ?'), ?']
-      keyword?(term) ->
-        surround_many(open, term, close, opts, &keyword/2, sep)
-      true ->
-        surround_many(open, term, close, opts, &to_doc/2, sep)
-    end
-  end
-
-  @doc false
-  def keyword({key, value}, opts) do
-    key = color(key_to_binary(key) <> ": ", :atom, opts)
-    concat(key, to_doc(value, opts))
-  end
-
-  @doc false
-  def keyword?([{key, _value} | rest]) when is_atom(key) do
-    case Atom.to_charlist(key) do
-      'Elixir.' ++ _ -> false
-      _ -> keyword?(rest)
-    end
-  end
-
-  def keyword?([]),     do: true
-  def keyword?(_other), do: false
-
-  @doc false
-  def printable?([char | rest]) when char in 32..126, do: printable?(rest)
-  def printable?([?\n | rest]), do: printable?(rest)
-  def printable?([?\r | rest]), do: printable?(rest)
-  def printable?([?\t | rest]), do: printable?(rest)
-  def printable?([?\v | rest]), do: printable?(rest)
-  def printable?([?\b | rest]), do: printable?(rest)
-  def printable?([?\f | rest]), do: printable?(rest)
-  def printable?([?\e | rest]), do: printable?(rest)
-  def printable?([?\a | rest]), do: printable?(rest)
-  def printable?([]), do: true
-  def printable?(_), do: false
-
-  ## Private
-
-  defp key_to_binary(key) do
-    case Inspect.Atom.inspect(key) do
-      ":" <> right -> right
-      other -> other
-    end
-  end
-end
-
-defimpl Inspect, for: Tuple do
-  def inspect(tuple, opts) do
-    open = color("{", :tuple, opts)
-    sep = color(",", :tuple, opts)
-    close = color("}", :tuple, opts)
-    surround_many(open, Tuple.to_list(tuple), close, opts, &to_doc/2, sep)
-  end
-end
-
-defimpl Inspect, for: Map do
-  def inspect(map, opts) do
-    nest inspect(map, "", opts), 1
-  end
-
-  def inspect(map, name, opts) do
-    map = :maps.to_list(map)
-    open = color("%" <> name <> "{", :map, opts)
-    sep = color(",", :map, opts)
-    close = color("}", :map, opts)
-    surround_many(open, map, close, opts, traverse_fun(map), sep)
-  end
-
-  defp traverse_fun(list) do
-    if Inspect.List.keyword?(list) do
-      &Inspect.List.keyword/2
-    else
-      &to_map/2
-    end
-  end
-
-  defp to_map({key, value}, opts) do
-    concat(
-      concat(to_doc(key, opts), " => "),
-      to_doc(value, opts)
-    )
-  end
-end
-
-defimpl Inspect, for: Integer do
-  def inspect(term, %Inspect.Opts{base: base} = opts) do
-    inspected = Integer.to_string(term, base_to_value(base)) |> prepend_prefix(base)
-    color(inspected, :number, opts)
-  end
-
-  defp base_to_value(base) do
-    case base do
-      :binary  -> 2
-      :decimal -> 10
-      :octal   -> 8
-      :hex     -> 16
-    end
-  end
-
-  defp prepend_prefix(value, :decimal), do: value
-  defp prepend_prefix(value, base) do
-    prefix = case base do
-      :binary -> "0b"
-      :octal  -> "0o"
-      :hex    -> "0x"
-    end
-    prefix <> value
-  end
-end
-
-defimpl Inspect, for: Float do
-  def inspect(term, opts) do
-    inspected = IO.iodata_to_binary(:io_lib_format.fwrite_g(term))
-    color(inspected, :number, opts)
-  end
-end
-
-defimpl Inspect, for: Regex do
-  def inspect(regex, opts) do
-    source = IO.iodata_to_binary(['~r/', escape(regex.source, ?/), ?/, regex.opts])
-    color(source, :regex, opts)
-  end
-
-  defp escape(bin, term),
-    do: escape(bin, [], term)
-
-  defp escape(<<?\\, term>> <> rest, buf, term),
-    do: escape(rest, [buf | [?\\, term]], term)
-
-  defp escape(<<term>> <> rest, buf, term),
-    do: escape(rest, [buf | [?\\, term]], term)
-
-  # The list of characters is from 'String.printable?' implementation
-  # minus characters treated specially by regex: \s, \d, \b, \e
-
-  defp escape(<<?\n>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\n'], term)
-
-  defp escape(<<?\r>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\r'], term)
-
-  defp escape(<<?\t>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\t'], term)
-
-  defp escape(<<?\v>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\v'], term)
-
-  defp escape(<<?\f>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\f'], term)
-
-  defp escape(<<?\a>> <> rest, buf, term),
-    do: escape(rest, [buf | '\\a'], term)
-
-  defp escape(<<char::utf8, rest::binary>>, buf, term)
-       when char in 0x20..0x7E
-       when char in 0xA0..0xD7FF
-       when char in 0xE000..0xFFFD
-       when char in 0x10000..0x10FFFF,
-    do: escape(rest, [buf | <<char::utf8>>], term)
-
-  defp escape(<<char, rest::binary>>, buf, term),
-    do: escape(rest, [buf | Inspect.BitString.escape_char(char)], term)
-
-  defp escape(<<>>, buf, _), do: buf
-end
-
-defimpl Inspect, for: Function do
-  def inspect(function, _opts) do
-    fun_info = :erlang.fun_info(function)
-    mod = fun_info[:module]
-
-    if fun_info[:type] == :external and fun_info[:env] == [] do
-      "&#{Inspect.Atom.inspect(mod)}.#{fun_info[:name]}/#{fun_info[:arity]}"
-    else
-      case Atom.to_charlist(mod) do
-        'elixir_compiler_' ++ _ ->
-          if function_exported?(mod, :__RELATIVE__, 0) do
-            "#Function<#{uniq(fun_info)} in file:#{mod.__RELATIVE__}>"
-          else
-            default_inspect(mod, fun_info)
-          end
-        _ ->
-          default_inspect(mod, fun_info)
-      end
-    end
-  end
-
-  defp default_inspect(mod, fun_info) do
-    "#Function<#{uniq(fun_info)}/#{fun_info[:arity]} in " <>
-      "#{Inspect.Atom.inspect(mod)}#{extract_name(fun_info[:name])}>"
-  end
-
-  defp extract_name([]) do
-    ""
-  end
-
-  defp extract_name(name) do
-    name = Atom.to_string(name)
-    case :binary.split(name, "-", [:global]) do
-      ["", name | _] -> "." <> name
-      _ -> "." <> name
-    end
-  end
-
-  defp uniq(fun_info) do
-    Integer.to_string(fun_info[:new_index]) <> "." <>
-      Integer.to_string(fun_info[:uniq])
-  end
-end
-
-defimpl Inspect, for: PID do
-  def inspect(pid, _opts) do
-    "#PID" <> IO.iodata_to_binary(:erlang.pid_to_list(pid))
-  end
-end
-
-defimpl Inspect, for: Port do
-  def inspect(port, _opts) do
-    IO.iodata_to_binary(:erlang.port_to_list(port))
-  end
-end
-
-defimpl Inspect, for: Reference do
-  def inspect(ref, _opts) do
-    '#Ref' ++ rest = :erlang.ref_to_list(ref)
-    "#Reference" <> IO.iodata_to_binary(rest)
-  end
-end
-
-defimpl Inspect, for: Any do
-  def inspect(%{__struct__: struct} = map, opts) do
-    try do
-      struct.__struct__
-    rescue
-      _ -> Inspect.Map.inspect(map, opts)
-    else
-      dunder ->
-        if :maps.keys(dunder) == :maps.keys(map) do
-          pruned = :maps.remove(:__exception__, :maps.remove(:__struct__, map))
-          colorless_opts = %{opts | syntax_colors: []}
-          Inspect.Map.inspect(pruned, Inspect.Atom.inspect(struct, colorless_opts), opts)
-        else
-          Inspect.Map.inspect(map, opts)
-        end
-    end
-  end
-end
@@ -1,662 +0,0 @@
-defmodule Inspect.Opts do
-  @moduledoc """
-  Defines the Inspect.Opts used by the Inspect protocol.
-
-  The following fields are available:
-
-    * `:structs` - when `false`, structs are not formatted by the inspect
-      protocol, they are instead printed as maps, defaults to `true`.
-
-    * `:binaries` - when `:as_strings` all binaries will be printed as strings,
-      non-printable bytes will be escaped.
-
-      When `:as_binaries` all binaries will be printed in bit syntax.
-
-      When the default `:infer`, the binary will be printed as a string if it
-      is printable, otherwise in bit syntax.
-
-    * `:charlists` - when `:as_charlists` all lists will be printed as char
-      lists, non-printable elements will be escaped.
-
-      When `:as_lists` all lists will be printed as lists.
-
-      When the default `:infer`, the list will be printed as a charlist if it
-      is printable, otherwise as list.
-
-    * `:limit` - limits the number of items that are printed for tuples,
-      bitstrings, and lists, does not apply to strings nor charlists, defaults
-      to 50.
-
-    * `:pretty` - if set to `true` enables pretty printing, defaults to `false`.
-
-    * `:width` - defaults to 80 characters, used when pretty is `true` or when
-      printing to IO devices. Set to 0 to force each item to be printed on its
-      own line.
-
-    * `:base` - prints integers as `:binary`, `:octal`, `:decimal`, or `:hex`, defaults
-      to `:decimal`. When inspecting binaries any `:base` other than `:decimal`
-      implies `binaries: :as_binaries`.
-
-    * `:safe` - when `false`, failures while inspecting structs will be raised
-      as errors instead of being wrapped in the `Inspect.Error` exception. This
-      is useful when debugging failures and crashes for custom inspect
-      implementations
-
-    * `:syntax_colors` - when set to a keyword list of colors the output will
-      be colorized. The keys are types and the values are the colors to use for
-      each type. e.g. `[number: :red, atom: :blue]`. Types can include
-      `:number`, `:atom`, `regex`, `:tuple`, `:map`, `:list`, and `:reset`.
-      Colors can be any `t:IO.ANSI.ansidata/0` as accepted by `IO.ANSI.format/1`.
-  """
-
-  # TODO: Deprecate char_lists key by v1.5
-  defstruct structs: true,
-            binaries: :infer,
-            charlists: :infer,
-            char_lists: :infer,
-            limit: 50,
-            width: 80,
-            base: :decimal,
-            pretty: false,
-            safe: true,
-            syntax_colors: []
-
-  @type color_key :: atom
-
-  # TODO: Deprecate char_lists key and :as_char_lists value by v1.5
-  @type t :: %__MODULE__{
-               structs: boolean,
-               binaries: :infer | :as_binaries | :as_strings,
-               charlists: :infer | :as_lists | :as_charlists,
-               char_lists: :infer | :as_lists | :as_char_lists,
-               limit: pos_integer | :infinity,
-               width: pos_integer | :infinity,
-               base: :decimal | :binary | :hex | :octal,
-               pretty: boolean,
-               safe: boolean,
-               syntax_colors: [{color_key, IO.ANSI.ansidata}]
-             }
-end
-
-defmodule Inspect.Error do
-  @moduledoc """
-  Raised when a struct cannot be inspected.
-  """
-  defexception [:message]
-end
-
-defmodule Inspect.Algebra do
-  @moduledoc ~S"""
-  A set of functions for creating and manipulating algebra
-  documents.
-
-  This module implements the functionality described in
-  ["Strictly Pretty" (2000) by Christian Lindig][0] with small
-  additions, like support for String nodes, and a custom
-  rendering function that maximises horizontal space use.
-
-      iex> Inspect.Algebra.empty
-      :doc_nil
-
-      iex> "foo"
-      "foo"
-
-  With the functions in this module, we can concatenate different
-  elements together and render them:
-
-      iex> doc = Inspect.Algebra.concat(Inspect.Algebra.empty, "foo")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["foo"]
-
-  The functions `nest/2`, `space/2` and `line/2` help you put the
-  document together into a rigid structure. However, the document
-  algebra gets interesting when using functions like `break/1`, which
-  converts the given string into a line break depending on how much space
-  there is to print. Let's glue two docs together with a break and then
-  render it:
-
-      iex> doc = Inspect.Algebra.glue("a", " ", "b")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["a", " ", "b"]
-
-  Notice the break was represented as is, because we haven't reached
-  a line limit. Once we do, it is replaced by a newline:
-
-      iex> doc = Inspect.Algebra.glue(String.duplicate("a", 20), " ", "b")
-      iex> Inspect.Algebra.format(doc, 10)
-      ["aaaaaaaaaaaaaaaaaaaa", "\n", "b"]
-
-  Finally, this module also contains Elixir related functions, a bit
-  tied to Elixir formatting, namely `surround/3` and `surround_many/5`.
-
-  ## Implementation details
-
-  The original Haskell implementation of the algorithm by [Wadler][1]
-  relies on lazy evaluation to unfold document groups on two alternatives:
-  `:flat` (breaks as spaces) and `:break` (breaks as newlines).
-  Implementing the same logic in a strict language such as Elixir leads
-  to an exponential growth of possible documents, unless document groups
-  are encoded explicitly as `:flat` or `:break`. Those groups are then reduced
-  to a simple document, where the layout is already decided, per [Lindig][0].
-
-  This implementation slightly changes the semantic of Lindig's algorithm
-  to allow elements that belong to the same group to be printed together
-  in the same line, even if they do not fit the line fully. This was achieved
-  by changing `:break` to mean a possible break and `:flat` to force a flat
-  structure. Then deciding if a break works as a newline is just a matter
-  of checking if we have enough space until the next break that is not
-  inside a group (which is still flat).
-
-  Custom pretty printers can be implemented using the documents returned
-  by this module and by providing their own rendering functions.
-
-    [0]: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.34.2200
-    [1]: http://homepages.inf.ed.ac.uk/wadler/papers/prettier/prettier.pdf
-
-  """
-
-  @surround_separator ","
-  @tail_separator " |"
-  @newline "\n"
-  @nesting 1
-  @break " "
-
-  # Functional interface to "doc" records
-
-  @type t :: :doc_nil | :doc_line | doc_cons | doc_nest | doc_break | doc_group | doc_color | binary
-
-  @typep doc_cons :: {:doc_cons, t, t}
-  defmacrop doc_cons(left, right) do
-    quote do: {:doc_cons, unquote(left), unquote(right)}
-  end
-
-  @typep doc_nest :: {:doc_nest, t, non_neg_integer}
-  defmacrop doc_nest(doc, indent) do
-    quote do: {:doc_nest, unquote(doc), unquote(indent) }
-  end
-
-  @typep doc_break :: {:doc_break, binary}
-  defmacrop doc_break(break) do
-    quote do: {:doc_break, unquote(break)}
-  end
-
-  @typep doc_group :: {:doc_group, t}
-  defmacrop doc_group(group) do
-    quote do: {:doc_group, unquote(group)}
-  end
-
-  @typep doc_color :: {:doc_color, t, IO.ANSI.ansidata}
-  defmacrop doc_color(doc, color) do
-    quote do: {:doc_color, unquote(doc), unquote(color)}
-  end
-
-  defmacrop is_doc(doc) do
-    if Macro.Env.in_guard?(__CALLER__) do
-      do_is_doc(doc)
-    else
-      var = quote do: doc
-      quote do
-        unquote(var) = unquote(doc)
-        unquote(do_is_doc(var))
-      end
-    end
-  end
-
-  defp do_is_doc(doc) do
-    quote do
-      is_binary(unquote(doc)) or
-      unquote(doc) in [:doc_nil, :doc_line] or
-      (is_tuple(unquote(doc)) and
-       elem(unquote(doc), 0) in [:doc_cons, :doc_nest, :doc_break, :doc_group, :doc_color])
-    end
-  end
-
-  @doc """
-  Converts an Elixir term to an algebra document
-  according to the `Inspect` protocol.
-  """
-  @spec to_doc(any, Inspect.Opts.t) :: t
-  def to_doc(term, opts)
-
-  def to_doc(%{__struct__: struct} = map, %Inspect.Opts{} = opts) when is_atom(struct) do
-    if opts.structs do
-      try do
-        Inspect.inspect(map, opts)
-      rescue
-        e ->
-          stacktrace = System.stacktrace
-
-          # Because we try to raise a nice error message in case
-          # we can't inspect a struct, there is a chance the error
-          # message itself relies on the struct being printed, so
-          # we need to trap the inspected messages to guarantee
-          # we won't try to render any failed instruct when building
-          # the error message.
-          if Process.get(:inspect_trap) do
-            Inspect.Map.inspect(map, opts)
-          else
-            try do
-              Process.put(:inspect_trap, true)
-
-              res = Inspect.Map.inspect(map, opts)
-              res = IO.iodata_to_binary(format(res, :infinity))
-
-              exception = Inspect.Error.exception(
-                message: "got #{inspect e.__struct__} with message " <>
-                         "#{inspect Exception.message(e)} while inspecting #{res}"
-              )
-
-              if opts.safe do
-                Inspect.inspect(exception, opts)
-              else
-                reraise(exception, stacktrace)
-              end
-            after
-              Process.delete(:inspect_trap)
-            end
-          end
-      end
-    else
-      Inspect.Map.inspect(map, opts)
-    end
-  end
-
-  def to_doc(arg, %Inspect.Opts{} = opts) do
-    Inspect.inspect(arg, opts)
-  end
-
-  @doc """
-  Returns a document entity used to represent nothingness.
-
-  ## Examples
-
-      iex> Inspect.Algebra.empty
-      :doc_nil
-
-  """
-  @spec empty() :: :doc_nil
-  def empty, do: :doc_nil
-
-  @doc """
-  Concatenates two document entities returning a new document.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.concat("hello", "world")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["hello", "world"]
-
-  """
-  @spec concat(t, t) :: t
-  def concat(doc1, doc2) when is_doc(doc1) and is_doc(doc2) do
-    doc_cons(doc1, doc2)
-  end
-
-  @doc """
-  Concatenates a list of documents returning a new document.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.concat(["a", "b", "c"])
-      iex> Inspect.Algebra.format(doc, 80)
-      ["a", "b", "c"]
-
-  """
-  @spec concat([t]) :: t
-  def concat(docs) when is_list(docs) do
-    fold_doc(docs, &concat(&1, &2))
-  end
-
-  @doc """
-  Colors a document if the `color_key` has a color in the options.
-  """
-  @spec color(t, Inspect.Opts.color_key, Inspect.Opts.t) :: doc_color
-  def color(doc, color_key, %Inspect.Opts{syntax_colors: syntax_colors}) when is_doc(doc) do
-    if precolor = Keyword.get(syntax_colors, color_key) do
-      postcolor = Keyword.get(syntax_colors, :reset, :reset)
-      concat(doc_color(doc, precolor), doc_color(empty(), postcolor))
-    else
-      doc
-    end
-  end
-
-  @doc ~S"""
-  Nests the given document at the given `level`.
-
-  Nesting will be appended to the line breaks.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.nest(Inspect.Algebra.glue("hello", "world"), 5)
-      iex> Inspect.Algebra.format(doc, 5)
-      ["hello", "\n     ", "world"]
-
-  """
-  @spec nest(t, non_neg_integer) :: doc_nest
-  def nest(doc, level)
-
-  def nest(doc, 0) when is_doc(doc) do
-    doc
-  end
-
-  def nest(doc, level) when is_doc(doc) and is_integer(level) and level > 0 do
-    doc_nest(doc, level)
-  end
-
-  @doc ~S"""
-  Returns a document entity representing a break based on the given
-  `string`.
-
-  This break can be rendered as a linebreak or as the given `string`,
-  depending on the `mode` of the chosen layout or the provided
-  separator.
-
-  ## Examples
-
-  Let's create a document by concatenating two strings with a break between
-  them:
-
-      iex> doc = Inspect.Algebra.concat(["a", Inspect.Algebra.break("\t"), "b"])
-      iex> Inspect.Algebra.format(doc, 80)
-      ["a", "\t", "b"]
-
-  Notice the break was represented with the given string, because we didn't
-  reach a line limit. Once we do, it is replaced by a newline:
-
-      iex> break = Inspect.Algebra.break("\t")
-      iex> doc = Inspect.Algebra.concat([String.duplicate("a", 20), break, "b"])
-      iex> Inspect.Algebra.format(doc, 10)
-      ["aaaaaaaaaaaaaaaaaaaa", "\n", "b"]
-
-  """
-  @spec break(binary) :: doc_break
-  def break(string) when is_binary(string), do: doc_break(string)
-
-  @doc """
-  Returns a document entity representing the default break.
-
-  Same as calling `break/1` with the default break.
-  """
-  @spec break() :: doc_break
-  def break(), do: doc_break(@break)
-
-  @doc """
-  Glues two documents together inserting the default break between them.
-
-  The break that is inserted between `left` and `right` is the one returned by
-  `break/0`.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.glue("hello", "world")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["hello", " ", "world"]
-
-  """
-  @spec glue(t, t) :: t
-  def glue(doc1, doc2), do: concat(doc1, concat(break(), doc2))
-
-  @doc """
-  Glues two documents (`doc1` and `doc2`) together inserting the given
-  break `break_string` between them.
-
-  For more information on how the break is inserted, see `break/1`.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.glue("hello", "\t", "world")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["hello", "\t", "world"]
-
-  """
-  @spec glue(t, binary, t) :: t
-  def glue(doc1, break_string, doc2) when is_binary(break_string),
-    do: concat(doc1, concat(break(break_string), doc2))
-
-  @doc ~S"""
-  Returns a group containing the specified document `doc`.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.group(
-      ...>   Inspect.Algebra.concat(
-      ...>     Inspect.Algebra.group(
-      ...>       Inspect.Algebra.concat(
-      ...>         "Hello,",
-      ...>         Inspect.Algebra.concat(
-      ...>           Inspect.Algebra.break,
-      ...>           "A"
-      ...>         )
-      ...>       )
-      ...>     ),
-      ...>     Inspect.Algebra.concat(
-      ...>       Inspect.Algebra.break,
-      ...>       "B"
-      ...>     )
-      ...> ))
-      iex> Inspect.Algebra.format(doc, 80)
-      ["Hello,", " ", "A", " ", "B"]
-      iex> Inspect.Algebra.format(doc, 6)
-      ["Hello,", "\n", "A", " ", "B"]
-
-  """
-  @spec group(t) :: doc_group
-  def group(doc) when is_doc(doc) do
-    doc_group(doc)
-  end
-
-  @doc """
-  Inserts a mandatory single space between two documents.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.space("Hughes", "Wadler")
-      iex> Inspect.Algebra.format(doc, 5)
-      ["Hughes", " ", "Wadler"]
-
-  """
-  @spec space(t, t) :: t
-  def space(doc1, doc2), do: concat(doc1, concat(" ", doc2))
-
-  @doc ~S"""
-  Inserts a mandatory linebreak between two documents.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.line("Hughes", "Wadler")
-      iex> Inspect.Algebra.format(doc, 80)
-      ["Hughes", "\n", "Wadler"]
-
-  """
-  @spec line(t, t) :: t
-  def line(doc1, doc2), do: concat(doc1, concat(:doc_line, doc2))
-
-  @doc """
-  Folds a list of documents into a document using the given folder function.
-
-  The list of documents is folded "from the right"; in that, this function is
-  similar to `List.foldr/3`, except that it doesn't expect an initial
-  accumulator and uses the last element of `docs` as the initial accumulator.
-
-  ## Examples
-
-      iex> docs = ["A", "B", "C"]
-      iex> docs = Inspect.Algebra.fold_doc(docs, fn(doc, acc) ->
-      ...>   Inspect.Algebra.concat([doc, "!", acc])
-      ...> end)
-      iex> Inspect.Algebra.format(docs, 80)
-      ["A", "!", "B", "!", "C"]
-
-  """
-  @spec fold_doc([t], ((t, t) -> t)) :: t
-  def fold_doc(docs, folder_fun)
-
-  def fold_doc([], _folder_fun),
-    do: empty()
-  def fold_doc([doc], _folder_fun),
-    do: doc
-  def fold_doc([doc | docs], folder_fun) when is_function(folder_fun, 2),
-    do: folder_fun.(doc, fold_doc(docs, folder_fun))
-
-  # Elixir conveniences
-
-  @doc ~S"""
-  Surrounds a document with characters.
-
-  Puts the given document `doc` between the `left` and `right` documents enclosing
-  and nesting it. The document is marked as a group, to show the maximum as
-  possible concisely together.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.surround("[", Inspect.Algebra.glue("a", "b"), "]")
-      iex> Inspect.Algebra.format(doc, 3)
-      ["[", "a", "\n ", "b", "]"]
-
-  """
-  @spec surround(t, t, t) :: t
-  def surround(left, doc, right) when is_doc(left) and is_doc(doc) and is_doc(right) do
-    group(concat(left, concat(nest(doc, @nesting), right)))
-  end
-
-  @doc ~S"""
-  Maps and glues a collection of items.
-
-  It uses the given `left` and `right` documents as surrounding and the
-  separator document `separator` to separate items in `docs`. A limit can be
-  passed: when this limit is reached, this function stops gluing and outputs
-  `"..."` instead.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]",
-      ...>         %Inspect.Opts{limit: :infinity}, fn i, _opts -> to_string(i) end)
-      iex> Inspect.Algebra.format(doc, 5) |> IO.iodata_to_binary
-      "[1,\n 2,\n 3,\n 4,\n 5]"
-
-      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]",
-      ...>         %Inspect.Opts{limit: 3}, fn i, _opts -> to_string(i) end)
-      iex> Inspect.Algebra.format(doc, 20) |> IO.iodata_to_binary
-      "[1, 2, 3, ...]"
-
-      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]",
-      ...>         %Inspect.Opts{limit: 3}, fn i, _opts -> to_string(i) end, "!")
-      iex> Inspect.Algebra.format(doc, 20) |> IO.iodata_to_binary
-      "[1! 2! 3! ...]"
-
-  """
-  @spec surround_many(t, [any], t, Inspect.Opts.t, (term, Inspect.Opts.t -> t), t) :: t
-  def surround_many(left, docs, right, %Inspect.Opts{} = opts, fun, separator \\ @surround_separator)
-      when is_doc(left) and is_list(docs) and is_doc(right) and is_function(fun, 2) and is_doc(separator) do
-    do_surround_many(left, docs, right, opts.limit, opts, fun, separator)
-  end
-
-  defp do_surround_many(left, [], right, _, _opts, _fun, _) do
-    concat(left, right)
-  end
-
-  defp do_surround_many(left, docs, right, limit, opts, fun, sep) do
-    surround(left, do_surround_many(docs, limit, opts, fun, sep), right)
-  end
-
-  defp do_surround_many(_, 0, _opts, _fun, _sep) do
-    "..."
-  end
-
-  defp do_surround_many([], _limit, _opts, _fun, _sep) do
-    :doc_nil
-  end
-
-  defp do_surround_many([h], limit, opts, fun, _sep) do
-    fun.(h, %{opts | limit: limit})
-  end
-
-  defp do_surround_many([h | t], limit, opts, fun, sep) when is_list(t) do
-    limit = decrement(limit)
-    h = fun.(h, %{opts | limit: limit})
-    t = do_surround_many(t, limit, opts, fun, sep)
-    do_join(h, t, sep)
-  end
-
-  defp do_surround_many([h | t], limit, opts, fun, _sep) do
-    limit = decrement(limit)
-    h = fun.(h, %{opts | limit: limit})
-    t = fun.(t, %{opts | limit: limit})
-    do_join(h, t, @tail_separator)
-  end
-
-  defp do_join(:doc_nil, :doc_nil, _), do: :doc_nil
-  defp do_join(h, :doc_nil, _),        do: h
-  defp do_join(:doc_nil, t, _),        do: t
-  defp do_join(h, t, sep),             do: glue(concat(h, sep), t)
-
-  defp decrement(:infinity), do: :infinity
-  defp decrement(counter),   do: counter - 1
-
-  @doc ~S"""
-  Formats a given document for a given width.
-
-  Takes the maximum width and a document to print as its arguments
-  and returns an IO data representation of the best layout for the
-  document to fit in the given width.
-
-  ## Examples
-
-      iex> doc = Inspect.Algebra.glue("hello", " ", "world")
-      iex> Inspect.Algebra.format(doc, 30) |> IO.iodata_to_binary()
-      "hello world"
-      iex> Inspect.Algebra.format(doc, 10) |> IO.iodata_to_binary()
-      "hello\nworld"
-
-  """
-  @spec format(t, non_neg_integer | :infinity) :: iodata
-  def format(doc, width) when is_doc(doc) and (width == :infinity or width >= 0) do
-    format(width, 0, [{0, default_mode(width), doc_group(doc)}])
-  end
-
-  defp default_mode(:infinity), do: :flat
-  defp default_mode(_),         do: :break
-
-  # Record representing the document mode to be rendered: flat or broken
-  @typep mode :: :flat | :break
-
-  @spec fits?(integer, [{integer, mode, t}]) :: boolean
-  defp fits?(w, _) when w < 0,                      do: false
-  defp fits?(_, []),                                do: true
-  defp fits?(_, [{_, _, :doc_line} | _]),           do: true
-  defp fits?(w, [{_, _, :doc_nil} | t]),            do: fits?(w, t)
-  defp fits?(w, [{i, m, doc_cons(x, y)} | t]),      do: fits?(w, [{i, m, x} | [{i, m, y} | t]])
-  defp fits?(w, [{i, m, doc_color(x, _)} | t]),    do: fits?(w, [{i, m, x} | t])
-  defp fits?(w, [{i, m, doc_nest(x, j)} | t]),      do: fits?(w, [{i + j, m, x} | t])
-  defp fits?(w, [{i, _, doc_group(x)} | t]),        do: fits?(w, [{i, :flat, x} | t])
-  defp fits?(w, [{_, _, s} | t]) when is_binary(s), do: fits?((w - byte_size(s)), t)
-  defp fits?(w, [{_, :flat, doc_break(s)} | t]),    do: fits?((w - byte_size(s)), t)
-  defp fits?(_, [{_, :break, doc_break(_)} | _]),   do: true
-
-  @spec format(integer | :infinity, integer, [{integer, mode, t}]) :: [binary]
-  defp format(_, _, []),                                do: []
-  defp format(w, _, [{i, _, :doc_line} | t]),           do: [indent(i) | format(w, i, t)]
-  defp format(w, k, [{_, _, :doc_nil} | t]),            do: format(w, k, t)
-  defp format(w, k, [{i, m, doc_cons(x, y)} | t]),      do: format(w, k, [{i, m, x} | [{i, m, y} | t]])
-  defp format(w, k, [{i, m, doc_nest(x, j)} | t]),      do: format(w, k, [{i + j, m, x} | t])
-  defp format(w, k, [{i, m, doc_group(x)} | t]),        do: format(w, k, [{i, m, x} | t])
-  defp format(w, k, [{i, m, doc_color(x, c)} | t]),     do: [ansi(c) | format(w, k, [{i, m, x} | t])]
-  defp format(w, k, [{_, _, s} | t]) when is_binary(s), do: [s | format(w, (k + byte_size(s)), t)]
-  defp format(w, k, [{_, :flat, doc_break(s)} | t]),    do: [s | format(w, (k + byte_size(s)), t)]
-  defp format(w, k, [{i, :break, doc_break(s)} | t]) do
-    k = k + byte_size(s)
-
-    if w == :infinity or fits?(w - k, t) do
-      [s | format(w, k, t)]
-    else
-      [indent(i) | format(w, i, t)]
-    end
-  end
-
-  defp ansi(color) do
-    IO.ANSI.format_fragment(color, true)
-  end
-
-  defp indent(0), do: @newline
-  defp indent(i), do: @newline <> :binary.copy(" ", i)
-end
@@ -1,408 +0,0 @@
-defmodule Integer do
-  @moduledoc """
-  Functions for working with integers.
-  """
-
-  import Bitwise
-
-  @doc """
-  Determines if `integer` is odd.
-
-  Returns `true` if the given `integer` is an odd number,
-  otherwise it returns `false`.
-
-  Allowed in guard clauses.
-
-  ## Examples
-
-      iex> Integer.is_odd(5)
-      true
-
-      iex> Integer.is_odd(6)
-      false
-
-      iex> Integer.is_odd(-5)
-      true
-
-      iex> Integer.is_odd(0)
-      false
-
-  """
-  defmacro is_odd(integer) do
-    quote do: (unquote(integer) &&& 1) == 1
-  end
-
-  @doc """
-  Determines if an `integer` is even.
-
-  Returns `true` if the given `integer` is an even number,
-  otherwise it returns `false`.
-
-  Allowed in guard clauses.
-
-  ## Examples
-
-      iex> Integer.is_even(10)
-      true
-
-      iex> Integer.is_even(5)
-      false
-
-      iex> Integer.is_even(-10)
-      true
-
-      iex> Integer.is_even(0)
-      true
-
-  """
-  defmacro is_even(integer) do
-    quote do: (unquote(integer) &&& 1) == 0
-  end
-
-  @doc """
-  Computes the modulo remainder of an integer division.
-
-  `Integer.mod/2` uses floored division, which means that
-  the result will always have the sign of the `divisor`.
-
-  Raises an `ArithmeticError` exception if one of the arguments is not an
-  integer, or when the `divisor` is `0`.
-
-  ## Examples
-
-      iex> Integer.mod(5, 2)
-      1
-      iex> Integer.mod(6, -4)
-      -2
-
-  """
-  @spec mod(integer, neg_integer | pos_integer) :: integer
-  def mod(dividend, divisor) do
-    remainder = rem(dividend, divisor)
-    if remainder * divisor < 0 do
-      remainder + divisor
-    else
-      remainder
-    end
-  end
-
-  @doc """
-  Performs a floored integer division.
-
-  Raises an `ArithmeticError` exception if one of the arguments is not an
-  integer, or when the `divisor` is `0`.
-
-  `Integer.floor_div/2` performs *floored* integer division. This means that
-  the result is always rounded towards negative infinity.
-
-  If you want to perform truncated integer division (rounding towards zero),
-  use `Kernel.div/2` instead.
-
-  ## Examples
-
-      iex> Integer.floor_div(5, 2)
-      2
-      iex> Integer.floor_div(6, -4)
-      -2
-      iex> Integer.floor_div(-99, 2)
-      -50
-
-  """
-  @spec floor_div(integer, neg_integer | pos_integer) :: integer
-  def floor_div(dividend, divisor) do
-    if (dividend * divisor < 0) and rem(dividend, divisor) != 0 do
-      div(dividend, divisor) - 1
-    else
-      div(dividend, divisor)
-    end
-  end
-
-  @doc """
-  Returns the ordered digits for the given `integer`.
-
-  An optional `base` value may be provided representing the radix for the returned
-  digits. This one must be an integer >= 2.
-
-  ## Examples
-
-      iex> Integer.digits(123)
-      [1, 2, 3]
-
-      iex> Integer.digits(170, 2)
-      [1, 0, 1, 0, 1, 0, 1, 0]
-
-      iex> Integer.digits(-170, 2)
-      [-1, 0, -1, 0, -1, 0, -1, 0]
-
-  """
-  @spec digits(integer, pos_integer) :: [integer, ...]
-  def digits(integer, base \\ 10)
-      when is_integer(integer) and is_integer(base) and base >= 2 do
-    do_digits(integer, base, [])
-  end
-
-  defp do_digits(digit, base, []) when abs(digit) < base,
-    do: [digit]
-  defp do_digits(digit, base, []) when digit == -base,
-    do: [-1, 0]
-  defp do_digits(base, base, []),
-    do: [1, 0]
-  defp do_digits(0, _base, acc),
-    do: acc
-  defp do_digits(integer, base, acc),
-    do: do_digits(div(integer, base), base, [rem(integer, base) | acc])
-
-  @doc """
-  Returns the integer represented by the ordered `digits`.
-
-  An optional `base` value may be provided representing the radix for the `digits`.
-  This one can be an integer >= 2.
-
-  ## Examples
-
-      iex> Integer.undigits([1, 2, 3])
-      123
-
-      iex> Integer.undigits([1, 4], 16)
-      20
-
-      iex> Integer.undigits([])
-      0
-
-  """
-  @spec undigits([integer], integer) :: integer
-  def undigits(digits, base \\ 10) when is_list(digits) and is_integer(base) and base >= 2 do
-    do_undigits(digits, base, 0)
-  end
-
-  defp do_undigits([], _base, 0),
-    do: 0
-  defp do_undigits([digit], base, 0) when is_integer(digit) and digit < base,
-    do: digit
-  defp do_undigits([1, 0], base, 0),
-    do: base
-  defp do_undigits([0 | tail], base, 0),
-    do: do_undigits(tail, base, 0)
-
-  defp do_undigits([], _base, acc),
-    do: acc
-  defp do_undigits([digit | _], base, _) when is_integer(digit) and digit >= base,
-    do: raise ArgumentError, "invalid digit #{digit} in base #{base}"
-  defp do_undigits([digit | tail], base, acc) when is_integer(digit),
-    do: do_undigits(tail, base, acc * base + digit)
-
-  @doc """
-  Parses a text representation of an integer.
-
-  An optional `base` to the corresponding integer can be provided.
-  If `base` is not given, 10 will be used.
-
-  If successful, returns a tuple in the form of `{integer, remainder_of_binary}`.
-  Otherwise `:error`.
-
-  Raises an error if `base` is less than 2 or more than 36.
-
-  If you want to convert a string-formatted integer directly to a integer,
-  `String.to_integer/1` or `String.to_integer/2` can be used instead.
-
-  ## Examples
-
-      iex> Integer.parse("34")
-      {34, ""}
-
-      iex> Integer.parse("34.5")
-      {34, ".5"}
-
-      iex> Integer.parse("three")
-      :error
-
-      iex> Integer.parse("34", 10)
-      {34, ""}
-
-      iex> Integer.parse("f4", 16)
-      {244, ""}
-
-      iex> Integer.parse("Awww++", 36)
-      {509216, "++"}
-
-      iex> Integer.parse("fab", 10)
-      :error
-
-      iex> Integer.parse("a2", 38)
-      ** (ArgumentError) invalid base 38
-
-  """
-  @spec parse(binary, 2..36) :: {integer, binary} | :error | no_return
-  def parse(binary, base \\ 10)
-
-  def parse("", base) when base in 2..36,
-    do: :error
-
-  def parse(binary, base) when is_binary(binary) and base in 2..36 do
-    parse_in_base(binary, base)
-  end
-
-  def parse(binary, base) when is_binary(binary) do
-    raise ArgumentError, "invalid base #{base}"
-  end
-
-  defp parse_in_base("-" <> bin, base) do
-    case do_parse(bin, base) do
-      {number, remainder} -> {-number, remainder}
-      :error -> :error
-    end
-  end
-
-  defp parse_in_base("+" <> bin, base) do
-    do_parse(bin, base)
-  end
-
-  defp parse_in_base(binary, base) when is_binary(binary) do
-    do_parse(binary, base)
-  end
-
-  defp do_parse(<<char, rest::binary>>, base) do
-    if valid_digit_in_base?(char, base) do
-      do_parse(rest, base, parse_digit(char))
-    else
-      :error
-    end
-  end
-
-  defp do_parse(_, _) do
-    :error
-  end
-
-  defp do_parse(<<char, rest::binary>> = bin, base, acc) do
-    if valid_digit_in_base?(char, base) do
-      do_parse(rest, base, base * acc + parse_digit(char))
-    else
-      {acc, bin}
-    end
-  end
-
-  defp do_parse(bitstring, _, acc) do
-    {acc, bitstring}
-  end
-
-  defp parse_digit(char) do
-    cond do
-      char in ?0..?9 -> char - ?0
-      char in ?A..?Z -> char - ?A + 10
-      true           -> char - ?a + 10
-    end
-  end
-
-  defp valid_digit_in_base?(char, base) do
-    if base <= 10 do
-      char in ?0..(?0 + base - 1)
-    else
-      char in ?0..?9 or char in ?A..(?A + base - 11) or char in ?a..(?a + base - 11)
-    end
-  end
-
-  @doc """
-  Returns a binary which corresponds to the text representation
-  of `integer`.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Integer.to_string(123)
-      "123"
-
-      iex> Integer.to_string(+456)
-      "456"
-
-      iex> Integer.to_string(-789)
-      "-789"
-
-      iex> Integer.to_string(0123)
-      "123"
-
-  """
-  @spec to_string(integer) :: String.t
-  def to_string(integer) do
-    :erlang.integer_to_binary(integer)
-  end
-
-  @doc """
-  Returns a binary which corresponds to the text representation
-  of `integer` in the given `base`.
-
-  `base` can be an integer between 2 and 36.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Integer.to_string(100, 16)
-      "64"
-
-      iex> Integer.to_string(-100, 16)
-      "-64"
-
-      iex> Integer.to_string(882681651, 36)
-      "ELIXIR"
-
-  """
-  @spec to_string(integer, 2..36) :: String.t
-  def to_string(integer, base) do
-    :erlang.integer_to_binary(integer, base)
-  end
-
-  @doc """
-  Returns a charlist which corresponds to the text representation of the given `integer`.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Integer.to_charlist(123)
-      '123'
-
-      iex> Integer.to_charlist(+456)
-      '456'
-
-      iex> Integer.to_charlist(-789)
-      '-789'
-
-      iex> Integer.to_charlist(0123)
-      '123'
-
-  """
-  @spec to_charlist(integer) :: charlist
-  def to_charlist(integer) do
-    :erlang.integer_to_list(integer)
-  end
-
-  @doc """
-  Returns a charlist which corresponds to the text representation of `integer` in the given `base`.
-
-  `base` can be an integer between 2 and 36.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Integer.to_charlist(100, 16)
-      '64'
-
-      iex> Integer.to_charlist(-100, 16)
-      '-64'
-
-      iex> Integer.to_charlist(882681651, 36)
-      'ELIXIR'
-
-  """
-  @spec to_charlist(integer, 2..36) :: charlist
-  def to_charlist(integer, base) do
-    :erlang.integer_to_list(integer, base)
-  end
-
-  # TODO: Deprecate by v1.5
-  @doc false
-  @spec to_char_list(integer) :: charlist
-  def to_char_list(integer), do: Integer.to_charlist(integer)
-end
@@ -1,534 +1,135 @@
 defmodule IO do
  @moduledoc """
-  Functions handling input/output (IO).
+  Module responsible for doing IO. The function in this
+  module expects an iodata as argument encoded in UTF-8.
+  An iodata can be:

-  Many functions in this module expect an IO device as an argument.
-  An IO device must be a PID or an atom representing a process.
-  For convenience, Elixir provides `:stdio` and `:stderr` as
-  shortcuts to Erlang's `:standard_io` and `:standard_error`.
-
-  The majority of the functions expect chardata, i.e. strings or
-  lists of characters and strings. In case another type is given,
-  functions will convert to string via the `String.Chars` protocol
-  (as shown in typespecs).
-
-  The functions starting with `bin` expect iodata as an argument,
-  i.e. binaries or lists of bytes and binaries.
-
-  ## IO devices
-
-  An IO device may be an atom or a PID. In case it is an atom,
-  the atom must be the name of a registered process. In addition,
-  Elixir provides two shortcuts:
-
-    * `:stdio` - a shortcut for `:standard_io`, which maps to
-      the current `Process.group_leader/0` in Erlang
-
-    * `:stderr` - a shortcut for the named process `:standard_error`
-      provided in Erlang
-
-  IO devices maintain their position, that means subsequent calls to any
-  reading or writing functions will start from the place when the device
-  was last accessed. Position of files can be changed using the
-  `:file.position/2` function.
+  * A list of integers representing a string. Any unicode
+    character must be represented with one entry in the list,
+    this entry being an integer with the codepoint value;
+  * A binary in which unicode characters are represented
+    with many bytes (Elixir's default representation);
+  * A list of binaries or a list of char lists (as described above);
+  * If none of the above, `to_binary` is invoked in the
+    given argument;

  """

-  @type device :: atom | pid
-  @type nodata :: {:error, term} | :eof
-  @type chardata() :: :unicode.chardata()
-
-  defmacrop is_iodata(data) do
-    quote do
-      is_list(unquote(data)) or is_binary(unquote(data))
-    end
-  end
-
  @doc """
-  Reads from the IO `device`.
+  Reads `count` bytes from the IO device. It returns:

-  The `device` is iterated by the given number of characters or line by line if
-  `:line` is given.
-  Alternatively, if `:all` is given, then whole `device` is returned.
+  * `data` - The input characters.

-  It returns:
+  * :eof - End of file was encountered.

-    * `data` - the output characters
-
-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
-
-  If `:all` is given, `:eof` is never returned, but an
-  empty string in case the device has reached EOF.
+  * {:error, reason} - Other (rare) error condition,
+    for instance {:error, :estale} if reading from an
+    NFS file system.
  """
-  @spec read(device, :all | :line | non_neg_integer) :: chardata | nodata
-  def read(device \\ :stdio, line_or_chars)
-
-  def read(device, :all) do
-    do_read_all(map_dev(device), "")
-  end
-
-  def read(device, :line) do
-    :io.get_line(map_dev(device), '')
-  end
-
-  def read(device, count) when is_integer(count) and count >= 0 do
-    :io.get_chars(map_dev(device), '', count)
-  end
-
-  defp do_read_all(mapped_dev, acc) do
-    case :io.get_line(mapped_dev, "") do
-      line when is_binary(line) -> do_read_all(mapped_dev, acc <> line)
-      :eof -> acc
-      other -> other
-    end
+  def read(device // :stdio, count) do
+    Erlang.io.get_chars(map_dev(device), "", count)
  end

  @doc """
-  Reads from the IO `device`. The operation is Unicode unsafe.
+  Read a line from the IO device. It returns:

-  The `device` is iterated by the given number of bytes or line by line if
-  `:line` is given.
-  Alternatively, if `:all` is given, then whole `device` is returned.
+  * `data` - The input characters.

-  It returns:
+  * :eof - End of file was encountered.

-    * `data` - the output bytes
+  * {:error, reason} - Other (rare) error condition,
+    for instance {:error, :estale} if reading from an
+    NFS file system.

-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
-
-  If `:all` is given, `:eof` is never returned, but an
-  empty string in case the device has reached EOF.
-
-  Note: do not use this function on IO devices in Unicode mode
-  as it will return the wrong result.
+  This function does the same as `gets/2`,
+  except the prompt is not required as argument.
  """
-  @spec binread(device, :all | :line | non_neg_integer) :: iodata | nodata
-  def binread(device \\ :stdio, line_or_chars)
-
-  def binread(device, :all) do
-    do_binread_all(map_dev(device), "")
-  end
-
-  def binread(device, :line) do
-    case :file.read_line(map_dev(device)) do
-      {:ok, data} -> data
-      other -> other
-    end
-  end
-
-  def binread(device, count) when is_integer(count) and count >= 0 do
-    case :file.read(map_dev(device), count) do
-      {:ok, data} -> data
-      other -> other
-    end
-  end
-
-  @read_all_size 4096
-  defp do_binread_all(mapped_dev, acc) do
-    case :file.read(mapped_dev, @read_all_size) do
-      {:ok, data} -> do_binread_all(mapped_dev, acc <> data)
-      :eof -> acc
-      other -> other
-    end
+  def readline(device // :stdio) do
+    Erlang.io.get_line(map_dev(device), "")
  end

  @doc """
-  Writes `item` to the given `device`.
+  Writes the given argument to the given device.
+  By default the device is the standard output.
+  The argument is expected to be a chardata (i.e.
+  a char list or an unicode binary).

-  By default the `device` is the standard output.
  It returns `:ok` if it succeeds.

  ## Examples

      IO.write "sample"
-      #=> sample
+      #=> "sample"

      IO.write :stderr, "error"
-      #=> error
+      #=> "error"

  """
-  @spec write(device, chardata | String.Chars.t) :: :ok
-  def write(device \\ :stdio, item) do
-    :io.put_chars map_dev(device), to_chardata(item)
+  def write(device // :stdio, item) do
+    Erlang.io.put_chars map_dev(device), to_iodata(item)
+  end
+
+  def print(device // :stdio, item) do
+    IO.puts "IO.print is deprecated in favor of IO.write"
+    Erlang.io.put_chars map_dev(device), to_iodata(item)
  end

  @doc """
-  Writes `item` as a binary to the given `device`.
-  No Unicode conversion happens.
-  The operation is Unicode unsafe.
-
-  Check `write/2` for more information.
-
-  Note: do not use this function on IO devices in Unicode mode
-  as it will return the wrong result.
+  Writes the argument to the device, similarly to write
+  but adds a new line at the end. The argument is expected
+  to be a chardata.
  """
-  @spec binwrite(device, iodata) :: :ok | {:error, term}
-  def binwrite(device \\ :stdio, item) when is_iodata(item) do
-    :file.write map_dev(device), item
+  def puts(device // :stdio, item) do
+    erl_dev = map_dev(device)
+    Erlang.io.put_chars erl_dev, to_iodata(item)
+    Erlang.io.nl(erl_dev)
  end

  @doc """
-  Writes `item` to the given `device`, similar to `write/2`,
-  but adds a newline at the end.
+  Inspects and writes the given argument to the device
+  followed by a new line. Returns the item given.
  """
-  @spec puts(device, chardata | String.Chars.t) :: :ok
-  def puts(device \\ :stdio, item) do
-    :io.put_chars map_dev(device), [to_chardata(item), ?\n]
-  end
-
-  @doc """
-  Writes a `message` to stderr, along with the given `stacktrace`.
-
-  This function also notifies the compiler a warning was printed
-  (in case --warnings-as-errors was enabled). It returns `:ok`
-  if it succeeds.
-
-  An empty list can be passed to avoid stacktrace printing.
-
-  ## Examples
-
-      stacktrace = [{MyApp, :main, 1, [file: 'my_app.ex', line: 4]}]
-      IO.warn "variable bar is unused", stacktrace
-      #=> warning: variable bar is unused
-      #=>   my_app.ex:4: MyApp.main/1
-
-  """
-  @spec warn(chardata | String.Chars.t, Exception.stacktrace) :: :ok
-  def warn(message, []) do
-    :elixir_errors.warn([to_chardata(message), ?\n])
-  end
-  def warn(message, stacktrace) when is_list(stacktrace) do
-    formatted = Enum.map_join(stacktrace, "\n  ", &Exception.format_stacktrace_entry(&1))
-    :elixir_errors.warn([to_chardata(message), ?\n, "  ", formatted, ?\n])
-  end
-
-  @doc """
-  Writes a `message` to stderr, along with the current stacktrace.
-
-  It returns `:ok` if it succeeds.
-
-  ## Examples
-
-      IO.warn "variable bar is unused"
-      #=> warning: variable bar is unused
-      #=>   (iex) evaluator.ex:108: IEx.Evaluator.eval/4
-
-  """
-  @spec warn(chardata | String.Chars.t) :: :ok
-  def warn(message) do
-    {:current_stacktrace, stacktrace} = Process.info(self(), :current_stacktrace)
-    warn(message, Enum.drop(stacktrace, 2))
-  end
-
-  @doc """
-  Inspects and writes the given `item` to the device.
-
-  It's important to note that it returns the given `item` unchanged.
-  This makes it possible to "spy" on values by inserting an
-  `IO.inspect/2` call almost anywhere in your code, for example,
-  in the middle of a pipeline.
-
-  It enables pretty printing by default with width of
-  80 characters. The width can be changed by explicitly
-  passing the `:width` option.
-
-  The output can be decorated with a label, by providing the `:label`
-  option to easily distinguish it from other `IO.inspect/2` calls.
-  The label will be printed before the inspected `item`.
-
-  See `Inspect.Opts` for a full list of remaining formatting options.
-
-  ## Examples
-
-      IO.inspect <<0, 1, 2>>, width: 40
-
-  Prints:
-
-      <<0, 1, 2>>
-
-  We can use the `:label` option to decorate the output:
-
-      IO.inspect 1..100, label: "a wonderful range"
-
-  Prints:
-
-      a wonderful range: 1..100
-
-  The `:label` option is especially useful with pipelines:
-
-      [1, 2, 3]
-      |> IO.inspect(label: "before")
-      |> Enum.map(&(&1 * 2))
-      |> IO.inspect(label: "after")
-      |> Enum.sum
-
-  Prints:
-
-      before: [1, 2, 3]
-      after: [2, 4, 6]
-
-  """
-  @spec inspect(item, Keyword.t) :: item when item: var
-  def inspect(item, opts \\ []) do
-    inspect :stdio, item, opts
-  end
-
-  @doc """
-  Inspects `item` according to the given options using the IO `device`.
-
-  See `inspect/2` for a full list of options.
-  """
-  @spec inspect(device, item, Keyword.t) :: item when item: var
-  def inspect(device, item, opts) when is_list(opts) do
-    label    = if (label = opts[:label]), do: [to_chardata(label), ": "], else: []
-    opts     = struct(Inspect.Opts, opts)
-    chardata = Inspect.Algebra.format(Inspect.Algebra.to_doc(item, opts), opts.width)
-    puts device, [label, chardata]
+  def inspect(device // :stdio, item) do
+    puts device, Kernel.inspect(item)
    item
  end

  @doc """
-  Gets a number of bytes from IO device `:stdio`.
+  Gets `count` bytes from the IO device. It returns:

-  If `:stdio` is a Unicode device, `count` implies
-  the number of Unicode codepoints to be retrieved.
-  Otherwise, `count` is the number of raw bytes to be retrieved.
+  * `data` - The input characters.

-  See `IO.getn/3` for a description of return values.
+  * :eof - End of file was encountered.

+  * {:error, reason} - Other (rare) error condition,
+    for instance {:error, :estale} if reading from an
+    NFS file system.
  """
-  @spec getn(chardata | String.Chars.t, pos_integer) :: chardata | nodata
-  @spec getn(device, chardata | String.Chars.t) :: chardata | nodata
-  def getn(prompt, count \\ 1)
-
-  def getn(prompt, count) when is_integer(count) and count > 0 do
-    getn(:stdio, prompt, count)
-  end
-
-  def getn(device, prompt) when not is_integer(prompt) do
-    getn(device, prompt, 1)
+  def getb(device // :stdio, prompt, count // 1) do
+    Erlang.io.get_chars(map_dev(device), to_iodata(prompt), count)
  end

  @doc """
-  Gets a number of bytes from the IO `device`.
+  Reads a line from the IO device. It returns:

-  If the IO `device` is a Unicode device, `count` implies
-  the number of Unicode codepoints to be retrieved.
-  Otherwise, `count` is the number of raw bytes to be retrieved.
+  * `data` - The characters in the line terminated
+    by a LF (or end of file).

-  It returns:
-
-    * `data` - the input characters
-
-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
+  * :eof - End of file was encountered.

+  * {:error, reason} - Other (rare) error condition,
+    for instance {:error, :estale} if reading from an
+    NFS file system.
  """
-  @spec getn(device, chardata | String.Chars.t, pos_integer) :: chardata | nodata
-  def getn(device, prompt, count) when is_integer(count) and count > 0 do
-    :io.get_chars(map_dev(device), to_chardata(prompt), count)
+  def gets(device // :stdio, prompt) do
+    Erlang.io.get_line(map_dev(device), to_iodata(prompt))
  end

-  @doc ~S"""
-  Reads a line from the IO `device`.
-
-  It returns:
-
-    * `data` - the characters in the line terminated
-      by a line-feed (LF) or end of file (EOF)
-
-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
-
-  ## Examples
-
-  To display "What is your name?" as a prompt and await user input:
-
-      IO.gets "What is your name?\n"
-
-  """
-  @spec gets(device, chardata | String.Chars.t) :: chardata | nodata
-  def gets(device \\ :stdio, prompt) do
-    :io.get_line(map_dev(device), to_chardata(prompt))
-  end
-
-  @doc """
-  Converts the IO `device` into an `IO.Stream`.
-
-  An `IO.Stream` implements both `Enumerable` and
-  `Collectable`, allowing it to be used for both read
-  and write.
-
-  The `device` is iterated by the given number of characters or line by line if
-  `:line` is given.
-
-  This reads from the IO as UTF-8. Check out
-  `IO.binstream/2` to handle the IO as a raw binary.
-
-  Note that an IO stream has side effects and every time
-  you go over the stream you may get different results.
-
-  ## Examples
-
-  Here is an example on how we mimic an echo server
-  from the command line:
-
-      Enum.each IO.stream(:stdio, :line), &IO.write(&1)
-
-  """
-  @spec stream(device, :line | pos_integer) :: Enumerable.t
-  def stream(device, line_or_codepoints)
-      when line_or_codepoints == :line
-      when is_integer(line_or_codepoints) and line_or_codepoints > 0 do
-    IO.Stream.__build__(map_dev(device), false, line_or_codepoints)
-  end
-
-  @doc """
-  Converts the IO `device` into an `IO.Stream`. The operation is Unicode unsafe.
-
-  An `IO.Stream` implements both `Enumerable` and
-  `Collectable`, allowing it to be used for both read
-  and write.
-
-  The `device` is iterated by the given number of bytes or line by line if
-  `:line` is given.
-  This reads from the IO device as a raw binary.
-
-  Note that an IO stream has side effects and every time
-  you go over the stream you may get different results.
-
-  Finally, do not use this function on IO devices in Unicode
-  mode as it will return the wrong result.
-
-  """
-  @spec binstream(device, :line | pos_integer) :: Enumerable.t
-  def binstream(device, line_or_bytes)
-      when line_or_bytes == :line
-      when is_integer(line_or_bytes) and line_or_bytes > 0 do
-    IO.Stream.__build__(map_dev(device), true, line_or_bytes)
-  end
-
-  @doc """
-  Converts chardata (a list of integers representing codepoints,
-  lists and strings) into a string.
-
-  In case the conversion fails, it raises an `UnicodeConversionError`.
-  If a string is given, it returns the string itself.
-
-  ## Examples
-
-      iex> IO.chardata_to_string([0x00E6, 0x00DF])
-      "æß"
-
-      iex> IO.chardata_to_string([0x0061, "bc"])
-      "abc"
-
-      iex> IO.chardata_to_string("string")
-      "string"
-
-  """
-  @spec chardata_to_string(chardata) :: String.t | no_return
-  def chardata_to_string(string) when is_binary(string) do
-    string
-  end
-
-  def chardata_to_string(list) when is_list(list) do
-    List.to_string(list)
-  end
-
-  @doc """
-  Converts iodata (a list of integers representing bytes, lists
-  and binaries) into a binary.
-  The operation is Unicode unsafe.
-
-  Notice that this function treats lists of integers as raw bytes
-  and does not perform any kind of encoding conversion. If you want
-  to convert from a charlist to a string (UTF-8 encoded), please
-  use `chardata_to_string/1` instead.
-
-  If this function receives a binary, the same binary is returned.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> bin1 = <<1, 2, 3>>
-      iex> bin2 = <<4, 5>>
-      iex> bin3 = <<6>>
-      iex> IO.iodata_to_binary([bin1, 1, [2, 3, bin2], 4 | bin3])
-      <<1, 2, 3, 1, 2, 3, 4, 5, 4, 6>>
-
-      iex> bin = <<1, 2, 3>>
-      iex> IO.iodata_to_binary(bin)
-      <<1, 2, 3>>
-
-  """
-  @spec iodata_to_binary(iodata) :: binary
-  def iodata_to_binary(item) do
-    :erlang.iolist_to_binary(item)
-  end
-
-  @doc """
-  Returns the size of an iodata.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> IO.iodata_length([1, 2 | <<3, 4>>])
-      4
-
-  """
-  @spec iodata_length(iodata) :: non_neg_integer
-  def iodata_length(item) do
-    :erlang.iolist_size(item)
-  end
-
-  @doc false
-  def each_stream(device, line_or_codepoints) do
-    case read(device, line_or_codepoints) do
-      :eof ->
-        {:halt, device}
-      {:error, reason} ->
-        raise IO.StreamError, reason: reason
-      data ->
-        {[data], device}
-    end
-  end
-
-  @doc false
-  def each_binstream(device, line_or_chars) do
-    case binread(device, line_or_chars) do
-      :eof ->
-        {:halt, device}
-      {:error, reason} ->
-        raise IO.StreamError, reason: reason
-      data ->
-        {[data], device}
-    end
-  end
-
-  @compile {:inline, map_dev: 1, to_chardata: 1}
-
-  # Map the Elixir names for standard IO and error to Erlang names
+  # Map the Elixir names for standard io and error to Erlang names
  defp map_dev(:stdio),  do: :standard_io
  defp map_dev(:stderr), do: :standard_error
-  defp map_dev(other) when is_atom(other) or is_pid(other) or is_tuple(other), do: other
+  defp map_dev(other),   do: other

-  defp to_chardata(list) when is_list(list), do: list
-  defp to_chardata(other), do: to_string(other)
+  defp to_iodata(io) when is_list(io) or is_binary(io), do: io
+  defp to_iodata(other), do: to_binary(other)
 end
@@ -1,252 +0,0 @@
-defmodule IO.ANSI.Sequence do
-  @moduledoc false
-
-  defmacro defsequence(name, code, terminator \\ "m") do
-    quote bind_quoted: [name: name, code: code, terminator: terminator] do
-      def unquote(name)() do
-        "\e[#{unquote(code)}#{unquote(terminator)}"
-      end
-
-      defp format_sequence(unquote(name)) do
-        unquote(name)()
-      end
-    end
-  end
-end
-
-defmodule IO.ANSI do
-  @moduledoc """
-  Functionality to render ANSI escape sequences.
-
-  [ANSI escape sequences](https://en.wikipedia.org/wiki/ANSI_escape_code)
-  are characters embedded in text used to control formatting, color, and
-  other output options on video text terminals.
-  """
-
-  import IO.ANSI.Sequence
-
-  @typep ansicode :: atom
-  @typep ansilist :: maybe_improper_list(char | ansicode | binary | ansilist, binary | ansicode | [])
-  @type  ansidata :: ansilist | ansicode | binary
-
-  @doc """
-  Checks if ANSI coloring is supported and enabled on this machine.
-
-  This function simply reads the configuration value for
-  `:ansi_enabled` in the `:elixir` application. The value is by
-  default `false` unless Elixir can detect during startup that
-  both `stdout` and `stderr` are terminals.
-  """
-  @spec enabled? :: boolean
-  def enabled? do
-    Application.get_env(:elixir, :ansi_enabled, false)
-  end
-
-  @doc "Sets foreground color."
-  @spec color(0..255) :: String.t
-  def color(code) when code in 0..255, do: "\e[38;5;#{code}m"
-
-  @doc ~S"""
-  Sets the foreground color from individual RGB values.
-
-  Valid values for each color are in the range 0 to 5.
-  """
-  @spec color(0..5, 0..5, 0..5) :: String.t
-  def color(r, g, b) when r in 0..5 and g in 0..5 and b in 0..5 do
-    color(16 + (36 * r) + (6 * g) + b)
-  end
-
-  @doc "Sets background color."
-  @spec color_background(0..255) :: String.t
-  def color_background(code) when code in 0..255, do: "\e[48;5;#{code}m"
-
-  @doc ~S"""
-  Sets the background color from individual RGB values.
-
-  Valid values for each color are in the range 0 to 5.
-  """
-  @spec color_background(0..5, 0..5, 0..5) :: String.t
-  def color_background(r, g, b) when r in 0..5 and g in 0..5 and b in 0..5 do
-    color_background(16 + (36 * r) + (6 * g) + b)
-  end
-
-  @doc "Resets all attributes."
-  defsequence :reset, 0
-
-  @doc "Bright (increased intensity) or bold."
-  defsequence :bright, 1
-
-  @doc "Faint (decreased intensity). Not widely supported."
-  defsequence :faint, 2
-
-  @doc "Italic: on. Not widely supported. Sometimes treated as inverse."
-  defsequence :italic, 3
-
-  @doc "Underline: single."
-  defsequence :underline, 4
-
-  @doc "Blink: slow. Less than 150 per minute."
-  defsequence :blink_slow, 5
-
-  @doc "Blink: rapid. MS-DOS ANSI.SYS; 150 per minute or more; not widely supported."
-  defsequence :blink_rapid, 6
-
-  @doc "Image: negative. Swap foreground and background."
-  defsequence :inverse, 7
-
-  @doc "Image: negative. Swap foreground and background."
-  defsequence :reverse, 7
-
-  @doc "Conceal. Not widely supported."
-  defsequence :conceal, 8
-
-  @doc "Crossed-out. Characters legible, but marked for deletion. Not widely supported."
-  defsequence :crossed_out, 9
-
-  @doc "Sets primary (default) font."
-  defsequence :primary_font, 10
-
-  for font_n <- [1, 2, 3, 4, 5, 6, 7, 8, 9] do
-    @doc "Sets alternative font #{font_n}."
-    defsequence :"font_#{font_n}", font_n + 10
-  end
-
-  @doc "Normal color or intensity."
-  defsequence :normal, 22
-
-  @doc "Not italic."
-  defsequence :not_italic, 23
-
-  @doc "Underline: none."
-  defsequence :no_underline, 24
-
-  @doc "Blink: off."
-  defsequence :blink_off, 25
-
-  @doc "Image: positive. Normal foreground and background."
-  defsequence :inverse_off, 27
-
-  @doc "Image: positive. Normal foreground and background."
-  defsequence :reverse_off, 27
-
-  colors = [:black, :red, :green, :yellow, :blue, :magenta, :cyan, :white]
-
-  for {color, code} <- Enum.with_index(colors) do
-    @doc "Sets foreground color to #{color}."
-    defsequence color, code + 30
-
-    @doc "Sets foreground color to light #{color}."
-    defsequence :"light_#{color}", code + 90
-
-    @doc "Sets background color to #{color}."
-    defsequence :"#{color}_background", code + 40
-
-    @doc "Sets background color to light #{color}."
-    defsequence :"light_#{color}_background", code + 100
-  end
-
-  @doc "Default text color."
-  defsequence :default_color, 39
-
-  @doc "Default background color."
-  defsequence :default_background, 49
-
-  @doc "Framed."
-  defsequence :framed, 51
-
-  @doc "Encircled."
-  defsequence :encircled, 52
-
-  @doc "Overlined."
-  defsequence :overlined, 53
-
-  @doc "Not framed or encircled."
-  defsequence :not_framed_encircled, 54
-
-  @doc "Not overlined."
-  defsequence :not_overlined, 55
-
-  @doc "Sends cursor home."
-  defsequence :home, "", "H"
-
-  @doc "Clears screen."
-  defsequence :clear, "2", "J"
-
-  @doc "Clears line."
-  defsequence :clear_line, "2", "K"
-
-  defp format_sequence(other) do
-    raise ArgumentError, "invalid ANSI sequence specification: #{inspect other}"
-  end
-
-  @doc ~S"""
-  Formats a chardata-like argument by converting named ANSI sequences into actual
-  ANSI codes.
-
-  The named sequences are represented by atoms.
-
-  It will also append an `IO.ANSI.reset/0` to the chardata when a conversion is
-  performed. If you don't want this behaviour, use `format_fragment/2`.
-
-  An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
-  By default checks if ANSI is enabled using the `enabled?/0` function.
-
-  ## Examples
-
-      iex> IO.ANSI.format(["Hello, ", :red, :bright, "world!"], true)
-      [[[[[[], "Hello, "] | "\e[31m"] | "\e[1m"], "world!"] | "\e[0m"]
-
-  """
-  def format(chardata, emit? \\ enabled?()) when is_boolean(emit?) do
-    do_format(chardata, [], [], emit?, :maybe)
-  end
-
-  @doc ~S"""
-  Formats a chardata-like argument by converting named ANSI sequences into actual
-  ANSI codes.
-
-  The named sequences are represented by atoms.
-
-  An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
-  By default checks if ANSI is enabled using the `enabled?/0` function.
-
-  ## Examples
-
-      iex> IO.ANSI.format_fragment([:bright, 'Word'], true)
-      [[[[[[] | "\e[1m"], 87], 111], 114], 100]
-
-  """
-  def format_fragment(chardata, emit? \\ enabled?()) when is_boolean(emit?) do
-    do_format(chardata, [], [], emit?, false)
-  end
-
-  defp do_format([term | rest], rem, acc, emit?, append_reset) do
-    do_format(term, [rest | rem], acc, emit?, append_reset)
-  end
-
-  defp do_format(term, rem, acc, true, append_reset) when is_atom(term) do
-    do_format([], rem, [acc | format_sequence(term)], true, !!append_reset)
-  end
-
-  defp do_format(term, rem, acc, false, append_reset) when is_atom(term) do
-    do_format([], rem, acc, false, append_reset)
-  end
-
-  defp do_format(term, rem, acc, emit?, append_reset) when not is_list(term) do
-    do_format([], rem, [acc, term], emit?, append_reset)
-  end
-
-  defp do_format([], [next | rest], acc, emit?, append_reset) do
-    do_format(next, rest, acc, emit?, append_reset)
-  end
-
-  defp do_format([], [], acc, true, true) do
-    [acc | IO.ANSI.reset]
-  end
-
-  defp do_format([], [], acc, _emit?, _append_reset) do
-    acc
-  end
-end
@@ -1,565 +0,0 @@
-defmodule IO.ANSI.Docs do
-  @moduledoc false
-
-  @bullets [?*, ?-, ?+]
-  @spaces [" ", "\n", "\t"]
-
-  @doc """
-  The default options used by this module.
-
-  The supported values are:
-
-    * `:enabled`           - toggles coloring on and off (true)
-    * `:doc_bold`          - bold text (bright)
-    * `:doc_code`          - code blocks (cyan)
-    * `:doc_headings`      - h1, h2, h3, h4, h5, h6 headings (yellow)
-    * `:doc_inline_code`   - inline code (cyan)
-    * `:doc_table_heading` - style for table headings
-    * `:doc_title`         - top level heading (reverse, yellow)
-    * `:doc_underline`     - underlined text (underline)
-    * `:width`             - the width to format the text (80)
-
-  Values for the color settings are strings with
-  comma-separated ANSI values.
-  """
-  def default_options do
-    [enabled:           true,
-     doc_bold:          [:bright],
-     doc_code:          [:cyan],
-     doc_headings:      [:yellow],
-     doc_inline_code:   [:cyan],
-     doc_table_heading: [:reverse],
-     doc_title:         [:reverse, :yellow],
-     doc_underline:     [:underline],
-     width:             80]
-  end
-
-  @doc """
-  Prints the head of the documentation (i.e. the function signature).
-
-  See `default_options/0` for docs on the supported options.
-  """
-  def print_heading(heading, options \\ []) do
-    IO.puts IO.ANSI.reset
-    options = Keyword.merge(default_options(), options)
-    width   = options[:width]
-    padding = div(width + String.length(heading), 2)
-    heading = heading |> String.pad_leading(padding) |> String.pad_trailing(width)
-    write(:doc_title, heading, options)
-    newline_after_block()
-  end
-
-  @doc """
-  Prints the documentation body.
-
-  In addition to the printing string, takes a set of options
-  defined in `default_options/1`.
-  """
-  def print(doc, options \\ []) do
-    options = Keyword.merge(default_options(), options)
-    doc
-    |> String.split(["\r\n", "\n"], trim: false)
-    |> Enum.map(&String.trim_trailing/1)
-    |> process([], "", options)
-  end
-
-  defp process([], text, indent, options) do
-    write_text(text, indent, options)
-  end
-
-  defp process(["# " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-  defp process(["## " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-  defp process(["### " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-  defp process(["#### " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-  defp process(["##### " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-  defp process(["###### " <> _ = heading | rest], text, indent, options) do
-    write_heading(heading, rest, text, indent, options)
-  end
-
-  defp process(["" | rest], text, indent, options) do
-    write_text(text, indent, options)
-    process(rest, [], indent, options)
-  end
-
-  defp process(["    " <> line | rest], text, indent, options) do
-    write_text(text, indent, options)
-    process_code(rest, [line], indent, options)
-  end
-
-  defp process(["```" <> _line | rest], text, indent, options) do
-    process_fenced_code_block(rest, text, indent, options, _delimiter = "```")
-  end
-
-  defp process(["~~~" <> _line | rest], text, indent, options) do
-    process_fenced_code_block(rest, text, indent, options, _delimiter = "~~~")
-  end
-
-  defp process(all=[line | rest], text, indent, options) do
-    {stripped, count} = strip_spaces(line, 0, :infinity)
-    cond do
-      link_label?(stripped, count) ->
-        write_text([line], indent, options, true)
-        process(rest, text, indent, options)
-      table_line?(stripped) and rest != [] and table_line?(hd(rest)) ->
-        write_text(text, indent, options)
-        process_table(all, indent, options)
-      true ->
-        process_rest(stripped, rest, count, text, indent, options)
-    end
-  end
-
-  ## Headings
-
-  defp write_heading(heading, rest, text, indent, options) do
-    write_text(text, indent, options)
-    write(:doc_headings, heading, options)
-    newline_after_block()
-    process(rest, [], "", options)
-  end
-
-  ## Lists
-
-  defp process_rest(stripped, rest, count, text, indent, options) do
-    case stripped do
-      <<bullet, ?\s, item::binary>> when bullet in @bullets ->
-        write_text(text, indent, options)
-        process_list("• ", item, rest, count, indent, options)
-      <<d1, ?., ?\s, item::binary>> when d1 in ?0..?9 ->
-        write_text(text, indent, options)
-        process_list(<<d1, ?., ?\s>>, item, rest, count, indent, options)
-      <<d1, d2, ?., ?\s, item::binary>> when d1 in ?0..?9 and d2 in ?0..?9 ->
-        write_text(text, indent, options)
-        process_list(<<d1, d2, ?., ?\s>>, item, rest, count, indent, options)
-      _ ->
-        process(rest, [stripped | text], indent, options)
-    end
-  end
-
-  defp process_list(entry, line, rest, count, indent, options) do
-    # The first list always win some extra padding
-    entry = if indent == "", do: "  " <> entry, else: entry
-    new_indent = indent <> String.duplicate(" ", String.length(entry))
-
-    {contents, rest, done} = process_list_next(rest, count, byte_size(new_indent), [])
-    process(contents, [indent <> entry <> line, :no_wrap], new_indent, options)
-
-    if done, do: newline_after_block()
-    process(rest, [], indent, options)
-  end
-
-  defp process_list_next([line | rest], count, max, acc) do
-    {stripped, next_count} = strip_spaces(line, 0, max)
-    case process_list_next_kind(stripped, rest, count, next_count) do
-      :next -> process_list_next(rest, count, max, [stripped | acc])
-      :done -> {Enum.reverse(acc), [line | rest], true}
-      :list -> {Enum.reverse(acc), [line | rest], false}
-    end
-  end
-
-  defp process_list_next([], _count, _max, acc) do
-    {Enum.reverse(acc), [], true}
-  end
-
-  defp process_list_next_kind(stripped, rest, count, next_count) do
-    case {stripped, rest} do
-      {<<bullet, ?\s, _::binary>>, _} when bullet in @bullets and next_count <= count ->
-        :list
-      {<<d1, ?., ?\s, _::binary>>, _} when d1 in ?0..?9 and next_count <= count ->
-        :list
-      {<<d1, d2, ?., ?\s, _::binary>>, _} when d1 in ?0..?9 and d2 in ?0..?9 and next_count <= count ->
-        :list
-      {"", [" " <> _ | _]} ->
-        :next
-      {"", _} ->
-        :done
-      _ ->
-        :next
-    end
-  end
-
-  ## Text
-
-  defp write_text(text, indent, options) do
-    case Enum.reverse(text) do
-      [:no_wrap | rest] -> write_text(rest, indent, options, true)
-      rest -> write_text(rest, indent, options, false)
-    end
-  end
-
-  defp write_text([], _indent, _options, _no_wrap) do
-    :ok
-  end
-
-  defp write_text(lines, indent, options, no_wrap) do
-    lines
-    |> Enum.join(" ")
-    |> handle_links
-    |> handle_inline(options)
-    |> String.split(@spaces)
-    |> write_with_wrap(options[:width] - byte_size(indent), indent, no_wrap)
-
-    unless no_wrap, do: newline_after_block()
-  end
-
-  ## Code blocks
-
-  defp process_code([], code, indent, options) do
-    write_code(code, indent, options)
-  end
-
-  # Blank line between code blocks
-  defp process_code(["", "    " <> line | rest], code, indent, options) do
-    process_code(rest, [line, "" | code], indent, options)
-  end
-
-  defp process_code(["    " <> line | rest], code, indent, options) do
-    process_code(rest, [line | code], indent, options)
-  end
-
-  defp process_code(rest, code, indent, options) do
-    write_code(code, indent, options)
-    process(rest, [], indent, options)
-  end
-
-  defp process_fenced_code_block(rest, text, indent, options, delimiter) do
-    write_text(text, indent, options)
-    process_fenced_code(rest, [], indent, options, delimiter)
-  end
-
-  defp process_fenced_code([], code, indent, options, _delimiter) do
-    write_code(code, indent, options)
-  end
-
-  defp process_fenced_code([line | rest], code, indent, options, delimiter) do
-    if line === delimiter do
-      process_code(rest, code, indent, options)
-    else
-      process_fenced_code(rest, [line | code], indent, options, delimiter)
-    end
-  end
-
-  defp write_code(code, indent, options) do
-    write(:doc_code, "#{indent}    #{Enum.join(Enum.reverse(code), "\n#{indent}    ")}", options)
-    newline_after_block()
-  end
-
-  ## Tables
-
-  defp process_table(lines, indent, options) do
-    {table, rest} = Enum.split_while(lines, &table_line?/1)
-    table_lines(table, options)
-    newline_after_block()
-    process(rest, [], indent, options)
-  end
-
-  defp table_lines(lines, options) do
-    lines = Enum.map(lines, &split_into_columns(&1, options))
-    count = Enum.map(lines, &length/1) |> Enum.max
-    lines = Enum.map(lines, &pad_to_number_of_columns(&1, count))
-
-    widths =
-      for line <- lines do
-        for {_col, length} <- line, do: length
-      end
-
-    col_widths = Enum.reduce(widths,
-                             List.duplicate(0, count),
-                             &max_column_widths/2)
-
-    render_table(lines, col_widths, options)
-  end
-
-  defp split_into_columns(line, options) do
-    line
-    |> String.trim("|")
-    |> String.trim()
-    |> String.split(" | ")
-    |> Enum.map(&render_column(&1, options))
-  end
-
-  defp render_column(col, options) do
-    col =
-      col
-      |> String.replace("\\\|", "|")
-      |> handle_links
-      |> handle_inline(options)
-    {col, length_without_escape(col, 0)}
-  end
-
-  defp pad_to_number_of_columns(cols, col_count),
-    do: cols ++ List.duplicate({"", 0}, col_count - length(cols))
-
-  defp max_column_widths(cols, widths),
-    do: Enum.zip(cols, widths) |> Enum.map(fn {a, b} -> max(a, b) end)
-
-  # If second line is heading separator, use the heading style on the first
-  defp render_table([first, second | rest], widths, options) do
-    combined = Enum.zip(first, widths)
-    if table_header?(second) do
-      draw_table_row(combined, options, :heading)
-      render_table(rest, widths, options)
-    else
-      draw_table_row(combined, options)
-      render_table([second | rest], widths, options)
-    end
-  end
-
-  defp render_table([first | rest], widths, options) do
-    combined = Enum.zip(first, widths)
-    draw_table_row(combined, options)
-    render_table(rest, widths, options)
-  end
-
-  defp render_table([], _, _),
-    do: nil
-
-  defp table_header?(row) do
-    Enum.all?(row, fn {col, _} -> table_header_column?(col) end)
-  end
-
-  defp table_header_column?(":" <> row), do: table_header_contents?(row)
-  defp table_header_column?(row), do: table_header_contents?(row)
-
-  defp table_header_contents?("-" <> row), do: table_header_contents?(row)
-  defp table_header_contents?(":"), do: true
-  defp table_header_contents?(""), do: true
-  defp table_header_contents?(_), do: false
-
-  defp draw_table_row(cols_and_widths, options, heading \\ false) do
-    columns =
-      Enum.map_join(cols_and_widths, " | ", fn {{col, length}, width} ->
-        col <> String.duplicate(" ", width - length)
-      end)
-
-    if heading do
-      write(:doc_table_heading, columns, options)
-    else
-      IO.puts columns
-    end
-  end
-
-  defp table_line?(line) do
-    line =~ " | "
-  end
-
-  ## Helpers
-
-  defp link_label?("[" <> rest, count) when count <= 3, do: link_label?(rest)
-  defp link_label?(_, _), do: false
-
-  defp link_label?("]: " <> _), do: true
-  defp link_label?("]" <> _), do: false
-  defp link_label?(""), do: false
-  defp link_label?(<<_>> <> rest), do: link_label?(rest)
-
-  defp strip_spaces(" " <> line, acc, max) when acc < max,
-    do: strip_spaces(line, acc + 1, max)
-  defp strip_spaces(rest, acc, _max),
-    do: {rest, acc}
-
-  defp write(style, string, options) do
-    IO.puts [color(style, options), string, IO.ANSI.reset]
-  end
-
-  defp write_with_wrap([], _available, _indent, _first) do
-    :ok
-  end
-
-  defp write_with_wrap(words, available, indent, first) do
-    {words, rest} = take_words(words, available, [])
-    IO.puts (if first, do: "", else: indent) <> Enum.join(words, " ")
-    write_with_wrap(rest, available, indent, false)
-  end
-
-  defp take_words([word | words], available, acc) do
-    available = available - length_without_escape(word, 0)
-
-    cond do
-      # It fits, take one for space and continue decreasing
-      available > 0 ->
-        take_words(words, available - 1, [word | acc])
-
-      # No space but we got no words
-      acc == [] ->
-        {[word], words}
-
-      # Otherwise
-      true ->
-        {Enum.reverse(acc), [word | words]}
-    end
-  end
-
-  defp take_words([], _available, acc) do
-    {Enum.reverse(acc), []}
-  end
-
-  defp length_without_escape(<<?\e, ?[, _, _, ?m>> <> rest, count) do
-    length_without_escape(rest, count)
-  end
-
-  defp length_without_escape(<<?\e, ?[, _, ?m>> <> rest, count) do
-    length_without_escape(rest, count)
-  end
-
-  defp length_without_escape(rest, count) do
-    case String.next_grapheme(rest) do
-      {_, rest} -> length_without_escape(rest, count + 1)
-      nil -> count
-    end
-  end
-
-  defp handle_links(text) do
-    text
-    |> remove_square_brackets_in_link
-    |> escape_underlines_in_link
-  end
-
-  defp escape_underlines_in_link(text) do
-    ~r{https?\S*}
-    |> Regex.recompile!
-    |> Regex.replace(text, &String.replace(&1, "_", "\\_"))
-  end
-
-  defp remove_square_brackets_in_link(text) do
-    ~r{\[(.*?)\]\((.*?)\)}
-    |> Regex.recompile!
-    |> Regex.replace(text, "\\1 (\\2)")
-  end
-
-  # We have four entries: **, *, _ and `.
-  #
-  # The first three behave the same while the last one is simpler
-  # when it comes to delimiters. But, since the first has two
-  # characters, we need to handle 3 cases:
-  #
-  # 1. **
-  # 2. _ and *
-  # 3. `
-  #
-  # Where the first two should have the same code but match differently.
-  @single [?_, ?*]
-
-  # Characters that can mark the beginning or the end of a word.
-  # Only support the most common ones at this moment.
-  @delimiters [?\s, ?', ?", ?!, ?@, ?#, ?$, ?%, ?^, ?&, ?-, ?+, ?(, ?), ?[, ?], ?{, ?}, ?<, ?>, ?.]
-
-  # Inline start
-
-  defp handle_inline(<<?*, ?*, rest::binary>>, options) do
-    handle_inline(rest, ?d, ["**"], [], options)
-  end
-
-  defp handle_inline(<<mark, rest::binary>>, options) when mark in @single do
-    handle_inline(rest, mark, [<<mark>>], [], options)
-  end
-
-  defp handle_inline(rest, options) do
-    handle_inline(rest, nil, [], [], options)
-  end
-
-  # Inline delimiters
-
-  defp handle_inline(<<delimiter, ?*, ?*, rest::binary>>, nil, buffer, acc, options)
-      when rest != "" and delimiter in @delimiters do
-    handle_inline(rest, ?d, ["**"], [delimiter, Enum.reverse(buffer) | acc], options)
-  end
-
-  defp handle_inline(<<delimiter, mark, rest::binary>>, nil, buffer, acc, options)
-      when rest != "" and delimiter in @delimiters and mark in @single do
-    handle_inline(rest, mark, [<<mark>>], [delimiter, Enum.reverse(buffer) | acc], options)
-  end
-
-  defp handle_inline(<<?`, rest::binary>>, nil, buffer, acc, options)
-      when rest != "" do
-    handle_inline(rest, ?`, ["`"], [Enum.reverse(buffer) | acc], options)
-  end
-
-  # Clauses for handling escape
-
-  defp handle_inline(<<?\\, ?\\, ?*, ?*, rest::binary>>, nil, buffer, acc, options)
-      when rest != "" do
-    handle_inline(rest, ?d, ["**"], [?\\, Enum.reverse(buffer) | acc], options)
-  end
-
-  defp handle_inline(<<?\\, ?\\, mark, rest::binary>>, nil, buffer, acc, options)
-      when rest != "" and mark in @single do
-    handle_inline(rest, mark, [<<mark>>], [?\\, Enum.reverse(buffer) | acc], options)
-  end
-
-  defp handle_inline(<<?\\, ?\\, rest::binary>>, limit, buffer, acc, options) do
-    handle_inline(rest, limit, [?\\ | buffer], acc, options)
-  end
-
-  # An escape is not valid inside `
-  defp handle_inline(<<?\\, mark, rest::binary>>, limit, buffer, acc, options)
-      when not(mark == limit and mark == ?`) do
-    handle_inline(rest, limit, [mark | buffer], acc, options)
-  end
-
-  # Inline end
-
-  defp handle_inline(<<?*, ?*, delimiter, rest::binary>>, ?d, buffer, acc, options)
-      when delimiter in @delimiters do
-    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer(buffer, options) | acc], options)
-  end
-
-  defp handle_inline(<<mark, delimiter, rest::binary>>, mark, buffer, acc, options)
-      when delimiter in @delimiters and mark in @single do
-    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer(buffer, options) | acc], options)
-  end
-
-  defp handle_inline(<<?*, ?*, rest::binary>>, ?d, buffer, acc, options)
-      when rest == "" do
-    handle_inline(<<>>, nil, [], [inline_buffer(buffer, options) | acc], options)
-  end
-
-  defp handle_inline(<<mark, rest::binary>>, mark, buffer, acc, options)
-      when rest == "" and mark in @single do
-    handle_inline(<<>>, nil, [], [inline_buffer(buffer, options) | acc], options)
-  end
-
-  defp handle_inline(<<?`, rest::binary>>, ?`, buffer, acc, options) do
-    handle_inline(rest, nil, [], [inline_buffer(buffer, options) | acc], options)
-  end
-
-  # Catch all
-
-  defp handle_inline(<<char, rest::binary>>, mark, buffer, acc, options) do
-    handle_inline(rest, mark, [char | buffer], acc, options)
-  end
-
-  defp handle_inline(<<>>, _mark, buffer, acc, _options) do
-    IO.iodata_to_binary Enum.reverse([Enum.reverse(buffer) | acc])
-  end
-
-  defp inline_buffer(buffer, options) do
-    [h | t] = Enum.reverse([IO.ANSI.reset | buffer])
-    [color_for(h, options) | t]
-  end
-
-  defp color_for(mark, colors) do
-    case mark do
-      "`"  -> color(:doc_inline_code, colors)
-      "_"  -> color(:doc_underline, colors)
-      "*"  -> color(:doc_bold, colors)
-      "**" -> color(:doc_bold, colors)
-    end
-  end
-
-  defp color(style, colors) do
-    color = colors[style]
-    IO.ANSI.format_fragment(color, colors[:enabled])
-  end
-
-  defp newline_after_block, do: IO.puts(IO.ANSI.reset)
-end
@@ -1,70 +0,0 @@
-defmodule IO.StreamError do
-  defexception [:reason, :message]
-
-  def exception(opts) do
-    reason    = opts[:reason]
-    formatted = IO.iodata_to_binary(:file.format_error(reason))
-    %IO.StreamError{message: "error during streaming: #{formatted}", reason: reason}
-  end
-end
-
-defmodule IO.Stream do
-  @moduledoc """
-  Defines an `IO.Stream` struct returned by `IO.stream/2` and `IO.binstream/2`.
-
-  The following fields are public:
-
-    * `device`        - the IO device
-    * `raw`           - a boolean indicating if bin functions should be used
-    * `line_or_bytes` - if reading should read lines or a given amount of bytes
-
-  It is worth noting that an IO stream has side effects and every time you go
-  over the stream you may get different results.
-
-  """
-
-  defstruct device: nil, raw: true, line_or_bytes: :line
-
-  @type t :: %__MODULE__{}
-
-  @doc false
-  def __build__(device, raw, line_or_bytes) do
-    %IO.Stream{device: device, raw: raw, line_or_bytes: line_or_bytes}
-  end
-
-  defimpl Collectable do
-    def into(%{device: device, raw: raw} = stream) do
-      {:ok, into(stream, device, raw)}
-    end
-
-    defp into(stream, device, raw) do
-      fn
-        :ok, {:cont, x} ->
-          case raw do
-            true  -> IO.binwrite(device, x)
-            false -> IO.write(device, x)
-          end
-        :ok, _ -> stream
-      end
-    end
-  end
-
-  defimpl Enumerable do
-    def reduce(%{device: device, raw: raw, line_or_bytes: line_or_bytes}, acc, fun) do
-      next_fun =
-        case raw do
-          true  -> &IO.each_binstream(&1, line_or_bytes)
-          false -> &IO.each_stream(&1, line_or_bytes)
-        end
-      Stream.resource(fn -> device end, next_fun, &(&1)).(acc, fun)
-    end
-
-    def count(_stream) do
-      {:error, __MODULE__}
-    end
-
-    def member?(_stream, _term) do
-      {:error, __MODULE__}
-    end
-  end
-end
@@ -1,455 +1,230 @@
+defrecord Kernel.CLI.Config, commands: [], output: ".",
+                             compile: [], halt: true, compiler_options: []
+
 defmodule Kernel.CLI do
  @moduledoc false

-  @blank_config %{commands: [], output: ".", compile: [],
-                  halt: true, compiler_options: [], errors: [],
-                  pa: [], pz: [], verbose_compile: false}
+  import Exception, only: [format_stacktrace: 1]

-  @doc """
-  This is the API invoked by Elixir boot process.
-  """
-  def main(argv) do
-    argv = for arg <- argv, do: IO.chardata_to_string(arg)
+  # Invoked directly from erlang boot process. It parses all argv
+  # options and execute them in the order they are specified.
+  def process_argv(options) do
+    { config, argv } = process_options(options, Kernel.CLI.Config.new)

-    {config, argv} = parse_argv(argv)
-    System.argv(argv)
+    argv = lc arg inlist argv, do: list_to_binary(arg)
+    Erlang.gen_server.call(:elixir_code_server, { :argv, argv })

-    run fn _ ->
-      errors = process_commands(config)
+    all_commands = List.reverse(config.commands)

-      if errors != [] do
-        Enum.each(errors, &IO.puts(:stderr, &1))
-        System.halt(1)
+    try do
+      Enum.map all_commands, process_command(&1, config)
+      if config.halt do
+        at_exit(0)
+        halt(0)
      end
-    end, config.halt
-  end
-
-  @doc """
-  Runs the given function by catching any failure
-  and printing them to stdout. `at_exit` hooks are
-  also invoked before exiting.
-
-  This function is used by Elixir's CLI and also
-  by escripts generated by Elixir.
-  """
-  def run(fun, halt \\ true) do
-    {ok_or_shutdown, status} = exec_fun(fun, {:ok, 0})
-    if ok_or_shutdown == :shutdown or halt do
-      {_, status} = at_exit({ok_or_shutdown, status})
-
-      # Ensure Logger messages are flushed before halting
-      case :erlang.whereis(Logger) do
-        pid when is_pid(pid) -> Logger.flush()
-        _ -> :ok
-      end
-
-      System.halt(status)
+    rescue
+      exception ->
+        at_exit(1)
+        stacktrace = System.stacktrace
+        IO.puts :stderr, "** (#{inspect exception.__record__(:name)}) #{exception.message}"
+        print_stacktrace(stacktrace)
+        halt(1)
+    catch
+      :exit, reason when is_integer(reason) ->
+        at_exit(reason)
+        halt(reason)
+      :exit, :normal ->
+        at_exit(0)
+        halt(0)
+      kind, reason ->
+        at_exit(1)
+        stacktrace = System.stacktrace
+        IO.puts :stderr, "** (#{kind}) #{inspect(reason)}"
+        print_stacktrace(stacktrace)
+        halt(1)
    end
  end

-  @doc false
-  def parse_argv(argv) do
-    parse_argv(argv, @blank_config)
-  end
+  ## Private

-  @doc false
-  def process_commands(config) do
-    results = Enum.map(Enum.reverse(config.commands), &process_command(&1, config))
-    errors  = for {:error, msg} <- results, do: msg
-    Enum.reverse(config.errors, errors)
-  end
-
-  ## Helpers
-
-  defp at_exit(res) do
-    hooks = :elixir_config.get_and_put(:at_exit, [])
-    res = Enum.reduce(hooks, res, &exec_fun/2)
-    if hooks == [], do: res, else: at_exit(res)
-  end
-
-  defp exec_fun(fun, res) when is_function(fun, 1) and is_tuple(res) do
-    parent = self()
-
-    {pid, ref} =
-      spawn_monitor(fn ->
-        try do
-          fun.(elem(res, 1))
-        catch
-          :exit, {:shutdown, int} when is_integer(int) ->
-            send parent, {self(), {:shutdown, int}}
-            exit({:shutdown, int})
-          :exit, reason
-              when reason == :normal
-              when reason == :shutdown
-              when tuple_size(reason) == 2 and elem(reason, 0) == :shutdown ->
-            send parent, {self(), {:shutdown, 0}}
-            exit(reason)
-          kind, reason ->
-            stack = System.stacktrace
-            print_error(kind, reason, stack)
-            send parent, {self(), {:shutdown, 1}}
-            exit(to_exit(kind, reason, stack))
-        else
-          _ ->
-            send parent, {self(), res}
-        end
-      end)
-
-    receive do
-      {^pid, res} ->
-        :erlang.demonitor(ref, [:flush])
-        res
-      {:DOWN, ^ref, _, _, other} ->
-        print_error({:EXIT, pid}, other, [])
-        {:shutdown, 1}
+  defp at_exit(status) do
+    hooks = Erlang.gen_server.call(:elixir_code_server, :at_exit)
+    lc hook inlist hooks do
+      try do
+        hook.(status)
+      rescue
+        exception ->
+          IO.puts :stderr, "** (#{inspect exception.__record__(:name)}) #{exception.message}"
+          print_stacktrace(System.stacktrace)
+      catch
+        kind, reason ->
+          IO.puts :stderr, "** #{kind} #{inspect(reason)}"
+          print_stacktrace(System.stacktrace)
+      end
    end
  end

-  defp to_exit(:throw, reason, stack), do: {{:nocatch, reason}, stack}
-  defp to_exit(:error, reason, stack), do: {reason, stack}
-  defp to_exit(:exit, reason, _stack), do: reason
+  defp invalid_option(option) do
+    IO.puts(:stderr, "Unknown option #{list_to_binary(option)}")
+    halt(1)
+  end

  defp shared_option?(list, config, callback) do
-    case parse_shared(list, config) do
-      {[h | hs], _} when h == hd(list) ->
-        new_config = %{config | errors: ["#{h} : Unknown option" | config.errors]}
-        callback.(hs, new_config)
-      {new_list, new_config} ->
+    case process_shared(list, config) do
+      { [h|t], _ } when h == hd(list) ->
+        invalid_option h
+      { new_list, new_config } ->
        callback.(new_list, new_config)
    end
  end

-  defp print_error(kind, reason, trace) do
-    IO.puts :stderr, Exception.format(kind, reason, prune_stacktrace(trace))
+  defp print_stacktrace(stacktrace) do
+    Enum.each stacktrace, fn s -> IO.puts :stderr, "    #{format_stacktrace(s)}" end
  end

-  @elixir_internals [:elixir, :elixir_exp, :elixir_compiler, :elixir_module, :elixir_clauses,
-                     :elixir_translator, :elixir_expand, :elixir_lexical, :elixir_exp_clauses,
-                     :elixir_def, :elixir_map]
+  # Process shared options

-  defp prune_stacktrace([{mod, _, _, _} | t]) when mod in @elixir_internals do
-    prune_stacktrace(t)
+  defp process_shared(['-v'|t], config) do
+    IO.puts "Elixir #{System.version}"
+    process_shared t, config
  end

-  defp prune_stacktrace([{__MODULE__, :wrapper, 1, _} | _]) do
-    []
+  defp process_shared(['--no-halt'|t], config) do
+    process_shared t, config.halt(false)
  end

-  defp prune_stacktrace([h | t]) do
-    [h | prune_stacktrace(t)]
+  defp process_shared(['-e',h|t], config) do
+    process_shared t, config.prepend_commands [eval: h]
  end

-  defp prune_stacktrace([]) do
-    []
+  defp process_shared(['-pa',h|t], config) do
+    Enum.each File.wildcard(File.expand_path(h)), Code.prepend_path(&1)
+    process_shared t, config
  end

-  # Parse shared options
+  defp process_shared(['-pz',h|t], config) do
+    Enum.each File.wildcard(File.expand_path(h)), Code.append_path(&1)
+    process_shared t, config
+  end

-  defp parse_shared([opt | _t], _config) when opt in ["-v", "--version"] do
-    if function_exported?(IEx, :started?, 0) and IEx.started? do
-      IO.puts "IEx " <> System.build_info[:build]
-    else
-      IO.puts :erlang.system_info(:system_version)
-      IO.puts "Elixir " <> System.build_info[:build]
+  defp process_shared(['-r',h|t], config) do
+    h = list_to_binary(h)
+    config = Enum.reduce File.wildcard(h), config, fn path, config ->
+      config.prepend_commands [require: path]
    end
-
-    System.halt 0
+    process_shared t, config
  end

-  defp parse_shared(["-pa", h | t], config) do
-    paths = expand_code_path(h)
-    Enum.each(paths, &:code.add_patha/1)
-    parse_shared t, %{config | pa: config.pa ++ paths}
+  defp process_shared(['-pr',h|t], config) do
+    h = list_to_binary(h)
+    process_shared t, config.prepend_commands [parallel_require: h]
  end

-  defp parse_shared(["-pz", h | t], config) do
-    paths = expand_code_path(h)
-    Enum.each(paths, &:code.add_pathz/1)
-    parse_shared t, %{config | pz: config.pz ++ paths}
+  defp process_shared([erl,_|t], config) when erl in ['--erl', '--sname', '--remsh', '--name'] do
+    process_shared t, config
  end

-  defp parse_shared(["--app", h | t], config) do
-    parse_shared t, %{config | commands: [{:app, h} | config.commands]}
-  end
-
-  defp parse_shared(["--no-halt" | t], config) do
-    parse_shared t, %{config | halt: false}
-  end
-
-  defp parse_shared(["-e", h | t], config) do
-    parse_shared t, %{config | commands: [{:eval, h} | config.commands]}
-  end
-
-  defp parse_shared(["-r", h | t], config) do
-    parse_shared t, %{config | commands: [{:require, h} | config.commands]}
-  end
-
-  defp parse_shared(["-pr", h | t], config) do
-    parse_shared t, %{config | commands: [{:parallel_require, h} | config.commands]}
-  end
-
-  defp parse_shared([erl, _ | t], config) when erl in ["--erl", "--sname", "--name", "--cookie", "--logger-otp-reports", "--logger-sasl-reports"] do
-    parse_shared t, config
-  end
-
-  defp parse_shared([erl | t], config) when erl in ["--detached", "--hidden", "--werl"] do
-    parse_shared t, config
-  end
-
-  defp parse_shared(list, config) do
-    {list, config}
-  end
-
-  defp expand_code_path(path) do
-    path = Path.expand(path)
-    case Path.wildcard(path) do
-      []   -> [to_charlist(path)]
-      list -> Enum.map(list, &to_charlist/1)
-    end
+  defp process_shared(list, config) do
+    { list, config }
  end

  # Process init options

-  defp parse_argv(["--" | t], config) do
-    {config, t}
+  def process_options(['--'|t], config) do
+    { config, t }
  end

-  defp parse_argv(["+elixirc" | t], config) do
-    parse_compiler t, config
+  def process_options(['--compile'|t], config) do
+    process_compiler t, config
  end

-  defp parse_argv(["+iex" | t], config) do
-    parse_iex t, config
-  end
-
-  defp parse_argv(["-S", h | t], config) do
-    {%{config | commands: [{:script, h} | config.commands]}, t}
-  end
-
-  defp parse_argv([h | t] = list, config) do
-    case h do
-      "-" <> _ ->
-        shared_option? list, config, &parse_argv(&1, &2)
-      _ ->
-        if Keyword.has_key?(config.commands, :eval) do
-          {config, list}
-        else
-          {%{config | commands: [{:file, h} | config.commands]}, t}
-        end
+  def process_options(['-S',h|t], config) do
+    exec = System.find_executable(h)
+    if exec do
+      { config.prepend_commands([require: list_to_binary(exec)]), t }
+    else
+      IO.puts(:stderr, "Could not find executable #{h}")
+      halt(1)
    end
  end

-  defp parse_argv([], config) do
-    {config, []}
-  end
-
-  # Parse compiler options
-
-  defp parse_compiler(["--" | t], config) do
-    {config, t}
-  end
-
-  defp parse_compiler(["-o", h | t], config) do
-    parse_compiler t, %{config | output: h}
-  end
-
-  defp parse_compiler(["--no-docs" | t], config) do
-    parse_compiler t, %{config | compiler_options: [{:docs, false} | config.compiler_options]}
-  end
-
-  defp parse_compiler(["--no-debug-info" | t], config) do
-    parse_compiler t, %{config | compiler_options: [{:debug_info, false} | config.compiler_options]}
-  end
-
-  defp parse_compiler(["--ignore-module-conflict" | t], config) do
-    parse_compiler t, %{config | compiler_options: [{:ignore_module_conflict, true} | config.compiler_options]}
-  end
-
-  defp parse_compiler(["--warnings-as-errors" | t], config) do
-    parse_compiler t, %{config | compiler_options: [{:warnings_as_errors, true} | config.compiler_options]}
-  end
-
-  defp parse_compiler(["--verbose" | t], config) do
-    parse_compiler t, %{config | verbose_compile: true}
-  end
-
-  defp parse_compiler([h | t] = list, config) do
+  def process_options([h|t] = list, config) do
    case h do
-      "-" <> _ ->
-        shared_option? list, config, &parse_compiler(&1, &2)
+      '-' ++ _ ->
+        shared_option? list, config, process_options(&1, &2)
      _ ->
+        h = list_to_binary(h)
+        { config.prepend_commands([require: h]), t }
+    end
+  end
+
+  def process_options([], config) do
+    { config, [] }
+  end
+
+  # Process compiler options
+
+  defp process_compiler(['--'|t], config) do
+    { config, t }
+  end
+
+  defp process_compiler(['-o',h|t], config) do
+    process_compiler t, config.output(list_to_binary(h))
+  end
+
+  defp process_compiler(['--no-docs'|t], config) do
+    process_compiler t, config.merge_compiler_options(docs: false)
+  end
+
+  defp process_compiler(['--debug-info'|t], config) do
+    process_compiler t, config.merge_compiler_options(debug_info: true)
+  end
+
+  defp process_compiler(['--ignore-module-conflict'|t], config) do
+    process_compiler t, config.merge_compiler_options(ignore_module_conflict: true)
+  end
+
+  defp process_compiler([h|t] = list, config) do
+    case h do
+      '-' ++ _ ->
+        shared_option? list, config, process_compiler(&1, &2)
+      _ ->
+        h = list_to_binary(h)
        pattern = if File.dir?(h), do: "#{h}/**/*.ex", else: h
-        parse_compiler t, %{config | compile: [pattern | config.compile]}
+        process_compiler t, config.prepend_compile [pattern]
    end
  end

-  defp parse_compiler([], config) do
-    {%{config | commands: [{:compile, config.compile} | config.commands]}, []}
-  end
-
-  # Parse IEx options
-
-  defp parse_iex(["--" | t], config) do
-    {config, t}
-  end
-
-  # This clause is here so that Kernel.CLI does not
-  # error out with "unknown option"
-  defp parse_iex(["--dot-iex", _ | t], config) do
-    parse_iex t, config
-  end
-
-  defp parse_iex([opt, _ | t], config) when opt in ["--remsh"] do
-    parse_iex t, config
-  end
-
-  defp parse_iex(["-S", h | t], config) do
-    {%{config | commands: [{:script, h} | config.commands]}, t}
-  end
-
-  defp parse_iex([h | t] = list, config) do
-    case h do
-      "-" <> _ ->
-        shared_option? list, config, &parse_iex(&1, &2)
-      _ ->
-        {%{config | commands: [{:file, h} | config.commands]}, t}
-    end
-  end
-
-  defp parse_iex([], config) do
-    {config, []}
+  defp process_compiler([], config) do
+    { config.prepend_commands([compile: config.compile]), [] }
  end

  # Process commands

-  defp process_command({:cookie, h}, _config) do
-    if Node.alive? do
-      wrapper fn -> Node.set_cookie(String.to_atom(h)) end
-    else
-      {:error, "--cookie : Cannot set cookie if the node is not alive (set --name or --sname)"}
-    end
+  defp process_command({:eval, expr}, _config) when is_list(expr) do
+    Erlang.elixir.eval(expr, [])
  end

-  defp process_command({:eval, expr}, _config) when is_binary(expr) do
-    wrapper fn -> Code.eval_string(expr, []) end
-  end
-
-  defp process_command({:app, app}, _config) when is_binary(app) do
-    case Application.ensure_all_started(String.to_atom(app)) do
-      {:error, {app, reason}} ->
-        {:error, "--app : Could not start application #{app}: " <>
-          Application.format_error(reason)}
-      {:ok, _} ->
-        :ok
-    end
-  end
-
-  defp process_command({:script, file}, _config) when is_binary(file) do
-    if exec = find_elixir_executable(file) do
-      wrapper fn -> Code.require_file(exec) end
-    else
-      {:error, "-S : Could not find executable #{file}"}
-    end
-  end
-
-  defp process_command({:file, file}, _config) when is_binary(file) do
-    if File.regular?(file) do
-      wrapper fn -> Code.require_file(file) end
-    else
-      {:error, "No file named #{file}"}
-    end
-  end
-
-  defp process_command({:require, pattern}, _config) when is_binary(pattern) do
-    files = filter_patterns(pattern)
-
-    if files != [] do
-      wrapper fn -> Enum.map files, &Code.require_file(&1) end
-    else
-      {:error, "-r : No files matched pattern #{pattern}"}
-    end
+  defp process_command({:require, file}, _config) when is_binary(file) do
+    Code.require_file(file)
  end

  defp process_command({:parallel_require, pattern}, _config) when is_binary(pattern) do
-    files = filter_patterns(pattern)
-
-    if files != [] do
-      wrapper fn -> Kernel.ParallelRequire.files(files) end
-    else
-      {:error, "-pr : No files matched pattern #{pattern}"}
-    end
+    files = File.wildcard(pattern)
+    files = List.uniq(files)
+    files = Enum.filter files, File.regular?(&1)
+    Kernel.ParallelRequire.files(files)
  end

  defp process_command({:compile, patterns}, config) do
-    # If ensuring the dir returns an error no files will be found.
-    _ = :filelib.ensure_dir(:filename.join(config.output, "."))
+    File.mkdir_p(config.output)

-    case filter_multiple_patterns(patterns) do
-      {:ok, []} ->
-        {:error, "No files matched provided patterns"}
-      {:ok, files} ->
-        wrapper fn ->
-          Code.compiler_options(config.compiler_options)
-          opts =
-            if config.verbose_compile do
-              [each_long_compilation: &IO.puts("Compiling #{&1} (it's taking more than 5s)")]
-            else
-              []
-            end
-          Kernel.ParallelCompiler.files_to_path(files, config.output, opts)
-        end
-      {:missing, missing} ->
-        {:error, "No files matched pattern(s) #{Enum.join(missing, ",")}"}
-    end
-  end
+    files = Enum.map patterns, File.wildcard(&1)
+    files = List.uniq(List.concat(files))
+    files = Enum.filter files, File.regular?(&1)

-  defp filter_patterns(pattern) do
-    pattern
-    |> Path.wildcard
-    |> :lists.usort
-    |> Enum.filter(&File.regular?/1)
-  end
-
-  defp filter_multiple_patterns(patterns) do
-    matched_files = Enum.map patterns, fn(pattern) ->
-      case filter_patterns(pattern) do
-        []    -> {:missing, pattern}
-        files -> {:ok, files}
-      end
-    end
-
-    files = Enum.filter_map matched_files,
-       fn(match) -> elem(match, 0) == :ok end,
-       &elem(&1, 1)
-
-    missing_patterns = Enum.filter_map matched_files,
-       fn(match) -> elem(match, 0) == :missing end,
-       &elem(&1, 1)
-
-    if missing_patterns == [] do
-      {:ok, :lists.usort(Enum.concat(files))}
-    else
-      {:missing, :lists.usort(missing_patterns)}
-    end
-  end
-
-  defp wrapper(fun) do
-    _ = fun.()
-    :ok
-  end
-
-  defp find_elixir_executable(file) do
-    if exec = System.find_executable(file) do
-      # If we are on Windows, the executable is going to be
-      # a .bat file that must be in the same directory as
-      # the actual Elixir executable.
-      case :os.type() do
-        {:win32, _} ->
-          base = Path.rootname(exec)
-          if File.regular?(base), do: base, else: exec
-        _ ->
-          exec
-      end
-    end
+    Code.compiler_options(config.compiler_options)
+    Kernel.ParallelCompiler.files_to_path(files, config.output,
+      fn file -> IO.puts "Compiled #{file}" end)
  end
 end
@@ -3,40 +3,25 @@
 defmodule Kernel.ErrorHandler do
  @moduledoc false

-  @spec undefined_function(module, atom, list) :: term
  def undefined_function(module, fun, args) do
-    ensure_loaded(module) or ensure_compiled(module, :module)
-    :error_handler.undefined_function(module, fun, args)
+    ensure_loaded(module)
+    Erlang.error_handler.undefined_function(module, fun, args)
  end

-  @spec undefined_lambda(module, fun, list) :: term
  def undefined_lambda(module, fun, args) do
-    ensure_loaded(module) or ensure_compiled(module, :module)
-    :error_handler.undefined_lambda(module, fun, args)
+    ensure_loaded(module)
+    Erlang.error_handler.undefined_lambda(module, fun, args)
  end

-  @spec ensure_loaded(module) :: boolean
-  def ensure_loaded(module) do
-    case :code.ensure_loaded(module) do
-      {:module, _} -> true
-      {:error, _} -> false
-    end
-  end
-
-  @spec ensure_compiled(module, atom) :: boolean
-  # Never wait on nil because it should never be defined.
-  def ensure_compiled(nil, _kind) do
-    false
-  end
-
-  def ensure_compiled(module, kind) do
-    parent = :erlang.get(:elixir_compiler_pid)
-    ref    = :erlang.make_ref
-    send parent, {:waiting, kind, self(), ref, module, :elixir_module.compiler_modules()}
-    :erlang.garbage_collect(self())
-    receive do
-      {^ref, :found}     -> true
-      {^ref, :not_found} -> false
+  defp ensure_loaded(module) do
+    case Code.ensure_loaded(module) do
+      { :module, _ } -> []
+      { :error, _ } ->
+        parent = Process.get(:elixir_compiler_pid)
+        parent <- { :waiting, self(), module }
+        receive do
+          { :release, ^parent } -> :ok
+        end
    end
  end
 end
@@ -1,246 +0,0 @@
-# This is an Elixir module responsible for tracking references
-# to modules, remote dispatches, and the usage of
-# aliases/imports/requires in the Elixir scope.
-#
-# Note that since this is required for bootstrap, we can't use
-# any of the `GenServer.Behaviour` conveniences.
-defmodule Kernel.LexicalTracker do
-  @moduledoc false
-  @timeout 30_000
-  @behaviour :gen_server
-
-  @doc """
-  Returns all remotes referenced in this lexical scope.
-  """
-  def remote_references(arg) do
-    :gen_server.call(to_pid(arg), :remote_references, @timeout)
-  end
-
-  @doc """
-  Returns all remote dispatches in this lexical scope.
-  """
-  def remote_dispatches(arg) do
-    :gen_server.call(to_pid(arg), :remote_dispatches, @timeout)
-  end
-
-  @doc """
-  Gets the destination the lexical scope is meant to
-  compile to.
-  """
-  def dest(arg) do
-    :gen_server.call(to_pid(arg), :dest, @timeout)
-  end
-
-  defp to_pid(pid) when is_pid(pid),  do: pid
-  defp to_pid(mod) when is_atom(mod) do
-    table = :elixir_module.data_table(mod)
-    [{_, val}] = :ets.lookup(table, {:elixir, :lexical_tracker})
-    val
-  end
-
-  # Internal API
-
-  # Starts the tracker and returns its PID.
-  @doc false
-  def start_link(dest) do
-    :gen_server.start_link(__MODULE__, dest, [])
-  end
-
-  @doc false
-  def stop(pid) do
-    :gen_server.cast(pid, :stop)
-  end
-
-  @doc false
-  def add_import(pid, module, fas, line, warn) when is_atom(module) do
-    :gen_server.cast(pid, {:add_import, module, fas, line, warn})
-  end
-
-  @doc false
-  def add_alias(pid, module, line, warn) when is_atom(module) do
-    :gen_server.cast(pid, {:add_alias, module, line, warn})
-  end
-
-  @doc false
-  def remote_reference(pid, module, mode) when is_atom(module) do
-    :gen_server.cast(pid, {:remote_reference, module, mode})
-  end
-
-  @doc false
-  def remote_dispatch(pid, module, fa, line, mode) when is_atom(module) do
-    :gen_server.cast(pid, {:remote_dispatch, module, fa, line, mode})
-  end
-
-  @doc false
-  def import_dispatch(pid, module, fa, line, mode) when is_atom(module) do
-    :gen_server.cast(pid, {:import_dispatch, module, fa, line, mode})
-  end
-
-  @doc false
-  def alias_dispatch(pid, module) when is_atom(module) do
-    :gen_server.cast(pid, {:alias_dispatch, module})
-  end
-
-  @doc false
-  def collect_unused_imports(pid) do
-    unused(pid, :import)
-  end
-
-  @doc false
-  def collect_unused_aliases(pid) do
-    unused(pid, :alias)
-  end
-
-  defp unused(pid, tag) do
-    :gen_server.call(pid, {:unused, tag}, @timeout)
-  end
-
-  # Callbacks
-
-  def init(dest) do
-    {:ok, %{directives: %{}, references: %{}, compile: %{},
-            runtime: %{}, dest: dest}}
-  end
-
-  @doc false
-  def handle_call({:unused, tag}, _from, state) do
-    directives =
-      for {{^tag, module_or_mfa}, marker} <- state.directives,
-          is_integer(marker),
-          do: {module_or_mfa, marker}
-
-    {:reply, Enum.sort(directives), state}
-  end
-
-  def handle_call(:remote_references, _from, state) do
-    {:reply, partition(Enum.to_list(state.references), [], []), state}
-  end
-
-  def handle_call(:remote_dispatches, _from, state) do
-    {:reply, {state.compile, state.runtime}, state}
-  end
-
-  def handle_call(:dest, _from, state) do
-    {:reply, state.dest, state}
-  end
-
-  def handle_cast({:remote_reference, module, mode}, state) do
-    {:noreply, %{state | references: add_reference(state.references, module, mode)}}
-  end
-
-  def handle_cast({:remote_dispatch, module, fa, line, mode}, state) do
-    references = add_reference(state.references, module, mode)
-    state = add_remote_dispatch(state, module, fa, line, mode)
-    {:noreply, %{state | references: references}}
-  end
-
-  def handle_cast({:import_dispatch, module, {function, arity} = fa, line, mode}, state) do
-    state =
-      state
-      |> add_import_dispatch(module, function, arity)
-      |> add_remote_dispatch(module, fa, line, mode)
-
-    {:noreply, state}
-  end
-
-  def handle_cast({:alias_dispatch, module}, state) do
-    {:noreply, %{state | directives: add_dispatch(state.directives, module, :alias)}}
-  end
-
-  def handle_cast({:add_import, module, fas, line, warn}, state) do
-    directives =
-      state.directives
-      |> Enum.reject(&match?({{:import, {^module, _, _}}, _}, &1))
-      |> :maps.from_list
-      |> add_directive(module, line, warn, :import)
-
-    directives =
-      Enum.reduce(fas, directives, fn {function, arity}, directives ->
-        add_directive(directives, {module, function, arity}, line, warn, :import)
-      end)
-
-    {:noreply, %{state | directives: directives}}
-  end
-
-  def handle_cast({:add_alias, module, line, warn}, state) do
-    {:noreply, %{state | directives: add_directive(state.directives, module, line, warn, :alias)}}
-  end
-
-  def handle_cast(:stop, state) do
-    {:stop, :normal, state}
-  end
-
-  @doc false
-  def handle_info(_msg, state) do
-    {:noreply, state}
-  end
-
-  @doc false
-  def terminate(_reason, _state) do
-    :ok
-  end
-
-  @doc false
-  def code_change(_old, state, _extra) do
-    {:ok, state}
-  end
-
-  defp partition([{remote, :compile} | t], compile, runtime),
-    do: partition(t, [remote | compile], runtime)
-  defp partition([{remote, :runtime} | t], compile, runtime),
-    do: partition(t, compile, [remote | runtime])
-  defp partition([], compile, runtime),
-    do: {compile, runtime}
-
-  # Callbacks helpers
-
-  defp add_reference(references, module, :runtime) when is_atom(module),
-    do: map_put_new(module, :runtime, references)
-  defp add_reference(references, module, :compile) when is_atom(module),
-    do: :maps.put(module, :compile, references)
-
-  defp add_remote_dispatch(state, module, fa, line, mode) when is_atom(module) do
-    map_update mode, %{module => %{fa => [line]}}, state, fn mode_dispatches ->
-      map_update module, %{fa => [line]}, mode_dispatches, fn module_dispatches ->
-        map_update fa, [line], module_dispatches, &[line | List.delete(&1, line)]
-      end
-    end
-  end
-
-  defp add_import_dispatch(state, module, function, arity) do
-    directives =
-      add_dispatch(state.directives, module, :import)
-      |> add_dispatch({module, function, arity}, :import)
-    # Always compile time because we depend
-    # on the module at compile time
-    references = add_reference(state.references, module, :compile)
-
-    %{state | directives: directives, references: references}
-  end
-
-  # In the map we keep imports and aliases.
-  # If the value is a line, it was imported/aliased and has a pending warning
-  # If the value is true, it was imported/aliased and used
-  defp add_directive(directives, module_or_mfa, line, warn, tag) do
-    marker = if warn, do: line, else: true
-    :maps.put({tag, module_or_mfa}, marker, directives)
-  end
-
-  defp add_dispatch(directives, module_or_mfa, tag) do
-    :maps.put({tag, module_or_mfa}, true, directives)
-  end
-
-  defp map_update(key, initial, map, fun) do
-    case :maps.find(key, map) do
-      {:ok, val} -> :maps.put(key, fun.(val), map)
-      :error -> :maps.put(key, initial, map)
-    end
-  end
-
-  defp map_put_new(key, value, map) do
-    case :maps.find(key, map) do
-      {:ok, _} -> map
-      :error -> :maps.put(key, value, map)
-    end
-  end
-end
@@ -1,8 +1,12 @@
 defmodule Kernel.ParallelCompiler do
+  alias Erlang.orddict, as: Orddict
+
  @moduledoc """
  A module responsible for compiling files in parallel.
  """

+  defmacrop default_callback, do: quote(do: fn x -> x end)
+
  @doc """
  Compiles the given files.

@@ -11,337 +15,103 @@ defmodule Kernel.ParallelCompiler do
  the current file stops being compiled until the dependency is
  resolved.

-  If there is an error during compilation or if `warnings_as_errors`
-  is set to `true` and there is a warning, this function will fail
-  with an exception.
-
-  This function accepts the following options:
-
-    * `:each_file` - for each file compiled, invokes the callback passing the
-      file
-
-    * `:each_long_compilation` - for each file that takes more than a given
-      timeout (see the `:long_compilation_threshold` option) to compile, invoke
-      this callback passing the file as its argument
-
-    * `:long_compilation_threshold` - the timeout (in seconds) after the
-      `:each_long_compilation` callback is invoked; defaults to `10`
-
-    * `:each_module` - for each module compiled, invokes the callback passing
-      the file, module and the module bytecode
-
-    * `:dest` - the destination directory for the BEAM files. When using `files/2`,
-      this information is only used to properly annotate the BEAM files before
-      they are loaded into memory. If you want a file to actually be written to
-      `dest`, use `files_to_path/3` instead.
-
-  Returns the modules generated by each compiled file.
+  A callback that is invoked every time a file is compiled
+  with its name can be optionally given as argument.
  """
-  def files(files, options \\ [])
-
-  def files(files, options) when is_list(options) do
-    spawn_compilers(files, nil, options)
+  def files(files, callback // default_callback) do
+    files_to_path(files, nil, callback)
  end

  @doc """
  Compiles the given files to the given path.
-  Read `files/2` for more information.
+  Read files/2 for more information.
  """
-  def files_to_path(files, path, options \\ [])
-
-  def files_to_path(files, path, options) when is_binary(path) and is_list(options) do
-    spawn_compilers(files, path, options)
+  def files_to_path(files, path, callback // default_callback) when is_binary(path) do
+    Code.ensure_loaded(Kernel.ErrorHandler)
+    spawn_compilers(files, path, callback, [], [], [])
  end

-  defp spawn_compilers(files, path, options) do
-    true = Code.ensure_loaded?(Kernel.ErrorHandler)
-    compiler_pid = self()
-    :elixir_code_server.cast({:reset_warnings, compiler_pid})
-    schedulers = max(:erlang.system_info(:schedulers_online), 2)
-
-    result = spawn_compilers(%{
-      entries: files,
-      original: files,
-      output: path,
-      options: options,
-      waiting: [],
-      queued: [],
-      schedulers: schedulers,
-      result: [],
-    })
-
-    # In case --warning-as-errors is enabled and there was a warning,
-    # compilation status will be set to error.
-    case :elixir_code_server.call({:compilation_status, compiler_pid}) do
-      :ok ->
-        result
-      :error ->
-        IO.puts :stderr, "Compilation failed due to warnings while using the --warnings-as-errors option"
-        exit({:shutdown, 1})
-    end
+  # We already have 4 currently running, don't spawn new ones
+  defp spawn_compilers(files, output, callback, waiting, queued, result) when
+      length(queued) - length(waiting) >= 4 do
+    wait_for_messages(files, output, callback, waiting, queued, result)
  end

-  # We already have n=schedulers currently running, don't spawn new ones
-  defp spawn_compilers(%{queued: queued, waiting: waiting, schedulers: schedulers} = state)
-      when length(queued) - length(waiting) >= schedulers do
-    wait_for_messages(state)
-  end
-
-  # Release waiting processes
-  defp spawn_compilers(%{entries: [{ref, found} | t], waiting: waiting} = state) do
-    waiting =
-      case List.keytake(waiting, ref, 2) do
-        {{_kind, pid, ^ref, _on, _defining}, waiting} ->
-          send pid, {ref, found}
-          waiting
-        nil ->
-          waiting
-      end
-    spawn_compilers(%{state | entries: t, waiting: waiting})
-  end
-
-  defp spawn_compilers(%{entries: [file | files], queued: queued, output: output, options: options} = state) do
+  # Spawn a compiler for each file in the list until we reach the limit
+  defp spawn_compilers([h|t], output, callback, waiting, queued, result) do
    parent = self()

-    {pid, ref} =
-      :erlang.spawn_monitor fn ->
-        # Set the elixir_compiler_pid used by our custom Kernel.ErrorHandler.
-        :erlang.put(:elixir_compiler_pid, parent)
-        :erlang.put(:elixir_compiler_file, file)
-        :erlang.process_flag(:error_handler, Kernel.ErrorHandler)
+    child  = spawn_link fn ->
+      Process.put(:elixir_compiler_pid, parent)
+      Process.flag(:error_handler, Kernel.ErrorHandler)

-        exit(try do
-          _ = if output do
-            :elixir_compiler.file_to_path(file, output)
-          else
-            :elixir_compiler.file(file, Keyword.get(options, :dest))
-          end
-          {:shutdown, file}
-        catch
-          kind, reason ->
-            {:failure, kind, reason, System.stacktrace}
-        end)
+      try do
+        if output do
+          Erlang.elixir_compiler.file_to_path(h, output)
+        else
+          Erlang.elixir_compiler.file(h)
+        end
+        parent <- { :compiled, self(), h }
+      catch
+        kind, reason ->
+          parent <- { :failure, self(), kind, reason, System.stacktrace }
      end
+    end

-    timeout = Keyword.get(options, :long_compilation_threshold, 10) * 1_000
-    timer_ref = Process.send_after(self(), {:timed_out, pid}, timeout)
-
-    new_queued = [{pid, ref, file, timer_ref} | queued]
-    spawn_compilers(%{state | entries: files, queued: new_queued})
+    spawn_compilers(t, output, callback, waiting, [{child,h}|queued], result)
  end

  # No more files, nothing waiting, queue is empty, we are done
-  defp spawn_compilers(%{entries: [], waiting: [], queued: [], result: result}) do
-    for {:module, mod} <- result, do: mod
-  end
+  defp spawn_compilers([], _output, _callback, [], [], result), do: result

  # Queued x, waiting for x: POSSIBLE ERROR! Release processes so we get the failures
-  defp spawn_compilers(%{entries: [], waiting: waiting, queued: queued} = state) when length(waiting) == length(queued) do
-    entries = for {pid, _, _, _} <- queued,
-                  entry = waiting_on_without_definition(waiting, pid),
-                  {_, _, ref, on, _} = entry,
-                  do: {on, {ref, :not_found}}
-
-    # Instead of releasing all files at once, we release them in groups
-    # based on the module they are waiting on. We pick the module being
-    # depended on with less edges, as it is the mostly likely source of
-    # error (for example, someone made a typo). This may not always be
-    # true though: for example, if there is a macro injecting code into
-    # multiple modules and such code becomes faulty, now multiple modules
-    # are waiting on the same module required by the faulty code. However,
-    # since we need to pick something to be first, the one with fewer edges
-    # sounds like a sane choice.
-    entries =
-      entries
-      |> Enum.group_by(&elem(&1, 0), &elem(&1, 1))
-      |> Enum.sort_by(&length(elem(&1, 1)))
-      |> Enum.find_value([], &elem(&1, 1))
-
-    case entries do
-      [] -> handle_deadlock(waiting, queued)
-      _  -> spawn_compilers(%{state | entries: entries})
-    end
+  defp spawn_compilers([], output, callback, waiting, queued, result) when length(waiting) == length(queued) do
+    Enum.each queued, fn { child, _ } -> child <- { :release, self() } end
+    wait_for_messages([], output, callback, waiting, queued, result)
  end

  # No more files, but queue and waiting are not full or do not match
-  defp spawn_compilers(%{entries: []} = state) do
-    wait_for_messages(state)
-  end
-
-  defp waiting_on_without_definition(waiting, pid) do
-    {_, ^pid, _, on, _} = entry = List.keyfind(waiting, pid, 1)
-    if Enum.any?(waiting, fn {_, _, _, _, defining} -> on in defining end) do
-      nil
-    else
-      entry
-    end
+  defp spawn_compilers([], output, callback, waiting, queued, result) do
+    wait_for_messages([], output, callback, waiting, queued, result)
  end

  # Wait for messages from child processes
-  defp wait_for_messages(state) do
-    %{entries: entries, options: options, waiting: waiting, queued: queued, result: result} = state
-
+  defp wait_for_messages(files, output, callback, waiting, queued, result) do
    receive do
-      {:struct_available, module} ->
-        available = for {:struct, _, ref, waiting_module, _defining} <- waiting,
-                        module == waiting_module,
-                        do: {ref, :found}
-
-        spawn_compilers(%{state | entries: available ++ entries, result: [{:struct, module} | result]})
-
-      {:module_available, child, ref, file, module, binary} ->
-        if callback = Keyword.get(options, :each_module) do
-          callback.(file, module, binary)
-        end
-
-        # Release the module loader which is waiting for an ack
-        send child, {ref, :ack}
-
-        available = for {:module, _, ref, waiting_module, _defining} <- waiting,
-                        module == waiting_module,
-                        do: {ref, :found}
-
-        cancel_waiting_timer(queued, child)
-
-        spawn_compilers(%{state | entries: available ++ entries, result: [{:module, module} | result]})
-
-      {:waiting, kind, child, ref, on, defining} ->
-        # Oops, we already got it, do not put it on waiting.
-        # Alternatively, we're waiting on ourselves,
-        # send :found so that we can crash with a better error.
-        waiting =
-          if :lists.any(&match?({^kind, ^on}, &1), result) or on in defining do
-            send child, {ref, :found}
-            waiting
-          else
-            [{kind, child, ref, on, defining} | waiting]
-          end
-
-        spawn_compilers(%{state | waiting: waiting})
-
-      {:timed_out, child} ->
-        callback = Keyword.get(options, :each_long_compilation)
-        case List.keyfind(queued, child, 0) do
-          {^child, _, file, _} when not is_nil(callback) ->
-            callback.(file)
-          _ ->
-            :ok
-        end
-        spawn_compilers(state)
-
-      {:DOWN, _down_ref, :process, down_pid, {:shutdown, file}} ->
-        if callback = Keyword.get(options, :each_file) do
-          callback.(file)
-        end
-
-        cancel_waiting_timer(queued, down_pid)
-
+      { :compiled, child, file } ->
+        callback.(file)
+        new_queued  = List.keydelete(queued, child, 1)
        # Sometimes we may have spurious entries in the waiting
        # list because someone invoked try/rescue UndefinedFunctionError
-        new_entries = List.delete(entries, down_pid)
-        new_queued  = List.keydelete(queued, down_pid, 0)
-        new_waiting = List.keydelete(waiting, down_pid, 1)
-        spawn_compilers(%{state | entries: new_entries, waiting: new_waiting, queued: new_queued})
-
-      {:DOWN, down_ref, :process, _down_pid, reason} ->
-        handle_failure(down_ref, reason, queued)
-        wait_for_messages(state)
-    end
-  end
-
-  defp handle_deadlock(waiting, queued) do
-    deadlock =
-      for {pid, _, file, _} <- queued do
-        {:current_stacktrace, stacktrace} = Process.info(pid, :current_stacktrace)
-        Process.exit(pid, :kill)
-
-        {_kind, ^pid, _, on, _} = List.keyfind(waiting, pid, 1)
-        error = CompileError.exception(description: "deadlocked waiting on module #{inspect on}",
-                                       file: nil, line: nil)
-        print_failure(file, {:failure, :error, error, stacktrace})
-
-        {file, on}
-      end
-
-    IO.puts """
-
-    Compilation failed because of a deadlock between files.
-    The following files depended on the following modules:
-    """
-
-    max =
-      deadlock
-      |> Enum.map(& &1 |> elem(0) |> String.length)
-      |> Enum.max
-
-    for {file, mod} <- deadlock do
-      IO.puts ["  ", String.pad_leading(file, max), " => " | inspect(mod)]
-    end
-
-    IO.puts ""
-    exit({:shutdown, 1})
-  end
-
-  defp handle_failure(ref, reason, queued) do
-    if file = find_failure(ref, queued) do
-      print_failure(file, reason)
-      for {pid, _, _, _} <- queued do
-        Process.exit(pid, :kill)
-      end
-      exit({:shutdown, 1})
-    end
-  end
-
-  defp find_failure(ref, queued) do
-    case List.keyfind(queued, ref, 1) do
-      {_child, ^ref, file, _timer_ref} -> file
-      _ -> nil
-    end
-  end
-
-  defp print_failure(_file, {:shutdown, _}) do
-    :ok
-  end
-
-  defp print_failure(file, {:failure, kind, reason, stacktrace}) do
-    IO.puts "\n== Compilation error on file #{Path.relative_to_cwd(file)} =="
-    IO.puts Exception.format(kind, reason, prune_stacktrace(stacktrace))
-  end
-
-  defp print_failure(file, reason) do
-    IO.puts "\n== Compilation error on file #{Path.relative_to_cwd(file)} =="
-    IO.puts Exception.format(:exit, reason, [])
-  end
-
-  @elixir_internals [:elixir, :elixir_exp, :elixir_compiler, :elixir_module, :elixir_clauses,
-                     :elixir_translator, :elixir_expand, :elixir_lexical, :elixir_exp_clauses,
-                     :elixir_def, :elixir_map, Kernel.ErrorHandler]
-
-  defp prune_stacktrace([{mod, _, _, _} | t]) when mod in @elixir_internals do
-    prune_stacktrace(t)
-  end
-
-  defp prune_stacktrace([h | t]) do
-    [h | prune_stacktrace(t)]
-  end
-
-  defp prune_stacktrace([]) do
-    []
-  end
-
-  defp cancel_waiting_timer(queued, child_pid) do
-    case List.keyfind(queued, child_pid, 0) do
-      {^child_pid, _ref, _file, timer_ref} ->
-        Process.cancel_timer(timer_ref)
-        # Let's flush the message in case it arrived before we canceled the
-        # timeout.
-        receive do
-          {:timed_out, ^child_pid} -> :ok
-        after
-          0 -> :ok
+        new_waiting = List.keydelete(waiting, child, 1)
+        spawn_compilers(files, output, callback, new_waiting, new_queued, result)
+      { :module_available, child, module, binary } ->
+        new_waiting = release_waiting_processes(module, waiting)
+        new_result  = [{module, binary}|result]
+        wait_for_messages(files, output, callback, new_waiting, queued, new_result)
+      { :waiting, child, on } ->
+        new_waiting = Orddict.store(child, on, waiting)
+        spawn_compilers(files, output, callback, new_waiting, queued, result)
+      { :failure, child, kind, reason, stacktrace } ->
+        extra = if match?({^child, module}, List.keyfind(waiting, child, 1)) do
+          " (undefined module #{inspect module})"
        end
-      nil ->
-        :ok
+
+      {^child, file} = List.keyfind(queued, child, 1)
+      IO.puts "== Compilation error on file #{file}#{extra} =="
+      Erlang.erlang.raise(kind, reason, stacktrace)
    end
  end
-end
+
+  # Release waiting processes that are waiting for the given module
+  defp release_waiting_processes(module, waiting) do
+    Enum.filter waiting, fn { child, waiting_module } ->
+      if waiting_module == module do
+        child <- { :release, self() }
+        false
+      else
+        true
+      end
+    end
+  end
+end
@@ -3,107 +3,49 @@ defmodule Kernel.ParallelRequire do
  A module responsible for requiring files in parallel.
  """

+  defmacrop default_callback, do: quote(do: fn x -> x end)
+
  @doc """
  Requires the given files.

-  A callback that will be invoked with each file, or a keyword list of `callbacks` can be provided:
-
-    * `:each_file` - invoked with each file
-
-    * `:each_module` - invoked with file, module name, and binary code
-
-  Returns the modules generated by each required file.
+  A callback that is invoked every time a file is required
+  can be optionally given as argument.
  """
-  def files(files, callbacks \\ [])
-
-  def files(files, callback) when is_function(callback, 1) do
-    files(files, [each_file: callback])
+  def files(files, callback // default_callback) do
+    spawn_requires(files, [], callback, [])
  end

-  def files(files, callbacks) when is_list(callbacks) do
-    compiler_pid = self()
-    :elixir_code_server.cast({:reset_warnings, compiler_pid})
-    schedulers = max(:erlang.system_info(:schedulers_online), 2)
-    result = spawn_requires(files, [], callbacks, schedulers, [])
+  defp spawn_requires([], [], _callback, result),     do: result
+  defp spawn_requires([], waiting, callback, result), do: wait_for_messages([], waiting, callback, result)

-    # In case --warning-as-errors is enabled and there was a warning,
-    # compilation status will be set to error.
-    case :elixir_code_server.call({:compilation_status, compiler_pid}) do
-      :ok ->
-        result
-      :error ->
-        IO.puts :stderr, "\nExecution failed due to warnings while using the --warnings-as-errors option"
-        exit({:shutdown, 1})
-    end
+  defp spawn_requires(files, waiting, callback, result) when length(waiting) >= 4 do
+    wait_for_messages(files, waiting, callback, result)
  end

-  defp spawn_requires([], [], _callbacks, _schedulers, result), do: result
+  defp spawn_requires([h|t], waiting, callback, result) do
+    parent = self

-  defp spawn_requires([], waiting, callbacks, schedulers, result) do
-    wait_for_messages([], waiting, callbacks, schedulers, result)
-  end
-
-  defp spawn_requires(files, waiting, callbacks, schedulers, result) when length(waiting) >= schedulers do
-    wait_for_messages(files, waiting, callbacks, schedulers, result)
-  end
-
-  defp spawn_requires([file | files], waiting, callbacks, schedulers, result) do
-    parent = self()
-    {pid, ref} = :erlang.spawn_monitor fn ->
-      :erlang.put(:elixir_compiler_pid, parent)
-      :erlang.put(:elixir_compiler_file, file)
-
-      exit(try do
-        new = Code.require_file(file) || []
-        {:required, Enum.map(new, &elem(&1, 0)), file}
+    child  = spawn_link fn ->
+      try do
+        new    = Code.require_file(h)
+        result = new ++ result
+        callback.(h)
+        parent <- { :required, self }
      catch
        kind, reason ->
-          {:failure, kind, reason, System.stacktrace}
-      end)
+          parent <- { :failure, self, kind, reason, System.stacktrace }
+      end
    end

-    spawn_requires(files, [{pid, ref} | waiting], callbacks, schedulers, result)
+    spawn_requires(t, [child|waiting], callback, result)
  end

-  defp wait_for_messages(files, waiting, callbacks, schedulers, result) do
+  defp wait_for_messages(files, waiting, callback, result) do
    receive do
-      {:DOWN, ref, :process, pid, status} ->
-        tuple = {pid, ref}
-        if tuple in waiting do
-          waiting = List.delete(waiting, tuple)
-
-          case status do
-            {:required, mods, file} ->
-              if each_file_callback = callbacks[:each_file] do
-                each_file_callback.(file)
-              end
-
-              spawn_requires(files, waiting, callbacks, schedulers, mods ++ result)
-
-            {:failure, kind, reason, stacktrace} ->
-              :erlang.raise(kind, reason, stacktrace)
-
-            other ->
-              :erlang.raise(:exit, other, [])
-          end
-        else
-          spawn_requires(files, waiting, callbacks, schedulers, result)
-        end
-
-      {:module_available, child, ref, file, module, binary} ->
-        if each_module_callback = callbacks[:each_module] do
-          each_module_callback.(file, module, binary)
-        end
-
-        send(child, {ref, :ack})
-        spawn_requires(files, waiting, callbacks, schedulers, result)
-
-      {:struct_available, _} ->
-        spawn_requires(files, waiting, callbacks, schedulers, result)
-
-      {:waiting, _, child, ref, _, _} ->
-        send(child, {ref, :not_found})
-        spawn_requires(files, waiting, callbacks, schedulers, result)
+      { :required, child } ->
+        spawn_requires(files, List.delete(waiting, child), callback, result)
+      { :failure, _child, kind, reason, stacktrace } ->
+        Erlang.erlang.raise(kind, reason, stacktrace)
    end
  end
-end
+end
@@ -1,126 +0,0 @@
-import Kernel, except: [destructure: 2, defdelegate: 2, defstruct: 2]
-
-defmodule Kernel.Utils do
-  @moduledoc false
-
-  @doc """
-  Callback for destructure.
-  """
-  def destructure(list, count) when is_list(list) and is_integer(count) and count >= 0,
-    do: destructure_list(list, count)
-  def destructure(nil, count) when is_integer(count) and count >= 0,
-    do: destructure_nil(count)
-
-  defp destructure_list(_, 0), do: []
-  defp destructure_list([], count), do: destructure_nil(count)
-  defp destructure_list([h | t], count), do: [h | destructure_list(t, count - 1)]
-
-  defp destructure_nil(0), do: []
-  defp destructure_nil(count), do: [nil | destructure_nil(count - 1)]
-
-  @doc """
-  Callback for defdelegate.
-  """
-  def defdelegate(fun, opts) when is_list(opts) do
-    # TODO: Remove by 2.0
-    append_first = Keyword.get(opts, :append_first, false)
-
-    {name, args} =
-      case Macro.decompose_call(fun) do
-        {_, _} = pair -> pair
-        _ -> raise ArgumentError, "invalid syntax in defdelegate #{Macro.to_string(fun)}"
-      end
-
-    as_args_list = normalize_args(args)
-    as = Keyword.get(opts, :as, name)
-    :lists.map(fn as_args ->
-      formal_args = make_formal_args(as_args)
-      as_args = case append_first do
-        true  -> tl(as_args) ++ [hd(as_args)]
-        false -> as_args
-      end
-      {name, formal_args, as, as_args}
-    end, as_args_list)
-  end
-
-  defp make_formal_args(args) do
-    fun = &match?({name, _, mod} when is_atom(name) and is_atom(mod), &1)
-    :lists.filter(fun, args)
-  end
-
-  defp normalize_args(raw_args) do
-    :lists.foldr(fn
-      ({:\\, _, [arg, default_arg]}, [as_args | _] = as_args_list) ->
-        new_as_args = [default_arg | as_args]
-        [new_as_args | add_arg(as_args_list, arg)]
-      (arg, as_args_list) ->
-        add_arg(as_args_list, arg)
-    end, [[]], raw_args)
-  end
-
-  defp add_arg(as_args_list, {name, _, mod} = arg) when is_atom(name) and is_atom(mod),
-    do: :lists.map(&([arg | &1]), as_args_list)
-  defp add_arg(_, code) do
-    raise ArgumentError,
-      "defdelegate/2 only accepts function parameters, got: #{Macro.to_string(code)}"
-  end
-
-  @doc """
-  Callback for defstruct.
-  """
-  def defstruct(module, fields) do
-    case fields do
-      fs when is_list(fs) ->
-        :ok
-      other ->
-        raise ArgumentError, "struct fields definition must be list, got: #{inspect other}"
-    end
-
-    fields = :lists.map(fn
-      {key, val} when is_atom(key) ->
-        try do
-          Macro.escape(val)
-        rescue
-          e in [ArgumentError] ->
-            raise ArgumentError, "invalid value for struct field #{key}, " <> Exception.message(e)
-        else
-          _ -> {key, val}
-        end
-      key when is_atom(key) ->
-        {key, nil}
-      other ->
-        raise ArgumentError, "struct field names must be atoms, got: #{inspect other}"
-    end, fields)
-
-    {:maps.put(:__struct__, module, :maps.from_list(fields)),
-     List.wrap(Module.get_attribute(module, :enforce_keys)),
-     Module.get_attribute(module, :derive)}
-  end
-
-  @doc """
-  Announcing callback for defstruct.
-  """
-  def announce_struct(module) do
-    case :erlang.get(:elixir_compiler_pid) do
-      :undefined -> :ok
-      pid -> send(pid, {:struct_available, module})
-    end
-  end
-
-  @doc """
-  Callback for raise.
-  """
-  def raise(msg) when is_binary(msg) do
-    RuntimeError.exception(msg)
-  end
-  def raise(atom) when is_atom(atom) do
-    atom.exception([])
-  end
-  def raise(%{__struct__: struct, __exception__: true} = exception) when is_atom(struct) do
-    exception
-  end
-  def raise(other) do
-    ArgumentError.exception("raise/1 expects an alias, string or exception as " <>
-                            "the first argument, got: #{inspect other}")
-  end
-end
@@ -1,56 +1,32 @@
 defprotocol List.Chars do
-  @moduledoc ~S"""
+  @moduledoc %B"""
  The List.Chars protocol is responsible for
  converting a structure to a list (only if applicable).
  The only function required to be implemented is
-  `to_charlist` which does the conversion.
+  `to_char_list` which does the conversion.

-  The `to_charlist/1` function automatically imported
-  by `Kernel` invokes this protocol.
+  The `to_char_list` function automatically imported
+  by Kernel invokes this protocol.
  """

-  def to_charlist(term)
+  @only [BitString, List, Atom, Number, Record]

-  # TODO: Deprecate by v1.5
-  @doc false
-  Kernel.def to_char_list(term) do
-    __MODULE__.to_charlist(term)
-  end
+  def to_char_list(thing)
 end

 defimpl List.Chars, for: Atom do
-  def to_charlist(atom), do: Atom.to_charlist(atom)
+  def to_char_list(atom), do: atom_to_list(atom)
 end

 defimpl List.Chars, for: BitString do
-  @doc """
-  Returns the given binary `term` converted to a charlist.
-  """
-  def to_charlist(term) when is_binary(term) do
-    String.to_charlist(term)
-  end
-
-  def to_charlist(term) do
-    raise Protocol.UndefinedError,
-             protocol: @protocol,
-                value: term,
-          description: "cannot convert a bitstring to a charlist"
-  end
+  def to_char_list(bitstring), do: bitstring_to_list(bitstring)
 end

 defimpl List.Chars, for: List do
-  # Note that same inlining is used for the rewrite rule.
-  def to_charlist(list), do: list
+  def to_char_list(list), do: list
 end

-defimpl List.Chars, for: Integer do
-  def to_charlist(term) do
-    Integer.to_charlist(term)
-  end
-end
-
-defimpl List.Chars, for: Float do
-  def to_charlist(term) do
-    :io_lib_format.fwrite_g(term)
-  end
-end
+defimpl List.Chars, for: Number do
+  def to_char_list(integer) when is_integer(integer), do: integer_to_list(integer)
+  def to_char_list(float)   when is_float(float),     do: float_to_list(float)
+end
@@ -1,144 +1,90 @@
+# We generate this record using a raw module due to
+# bootstrap constraints. Notice the fields are not
+# represented by a keywords list because we want
+# to keep control over the order.
 defmodule Macro.Env do
-  @moduledoc """
-  A struct that holds compile time environment information.
-
-  The current environment can be accessed at any time as
-  `__ENV__/0`. Inside macros, the caller environment can be
-  accessed as `__CALLER__/0`.
-
-  An instance of `Macro.Env` must not be modified by hand. If you need to
-  create a custom environment to pass to `Code.eval_quoted/3`, use the
-  following trick:
-
-      def make_custom_env do
-        import SomeModule, only: [some_function: 2]
-        alias A.B.C
-        __ENV__
-      end
-
-  You may then call `make_custom_env()` to get a struct with the desired
-  imports and aliases included.
-
-  It contains the following fields:
-
-    * `module` - the current module name
-    * `file` - the current file name as a binary
-    * `line` - the current line as an integer
-    * `function` - a tuple as `{atom, integer}`, where the first
-      element is the function name and the second its arity; returns
-      `nil` if not inside a function
-    * `context` - the context of the environment; it can be `nil`
-      (default context), inside a guard or inside a match
-    * `aliases` -  a list of two-element tuples, where the first
-      element is the aliased name and the second one the actual name
-    * `requires` - the list of required modules
-    * `functions` - a list of functions imported from each module
-    * `macros` - a list of macros imported from each module
-    * `macro_aliases` - a list of aliases defined inside the current macro
-    * `context_modules` - a list of modules defined in the current context
-    * `vars` - a list keeping all defined variables as `{var, context}`
-    * `export_vars` - a list keeping all variables to be exported in a
-      construct (may be `nil`)
-    * `lexical_tracker` - PID of the lexical tracker which is responsible for
-      keeping user info
+  @doc """
+  A record that contains compile time environment information,
+  It can be accessed at any time by calling __ENV__.
  """

-  @type name_arity :: {atom, arity}
-  @type file :: binary
-  @type line :: non_neg_integer
-  @type aliases :: [{module, module}]
-  @type macro_aliases :: [{module, {integer, module}}]
-  @type context :: :match | :guard | nil
-  @type requires :: [module]
-  @type functions :: [{module, [name_arity]}]
-  @type macros :: [{module, [name_arity]}]
-  @type context_modules :: [module]
-  @type vars :: [{atom, atom | non_neg_integer}]
-  @type export_vars :: vars | nil
-  @type lexical_tracker :: pid
-  @type local :: atom | nil
-
-  @type t :: %{__struct__: __MODULE__,
-               module: atom,
-               file: file,
-               line: line,
-               function: name_arity | nil,
-               context: context,
-               requires: requires,
-               aliases: aliases,
-               functions: functions,
-               macros: macros,
-               macro_aliases: aliases,
-               context_modules: context_modules,
-               vars: vars,
-               export_vars: export_vars,
-               lexical_tracker: lexical_tracker}
-
-  def __struct__ do
-    %{__struct__: __MODULE__,
-      module: nil,
-      file: "nofile",
-      line: 0,
-      function: nil,
-      context: nil,
-      requires: [],
-      aliases: [],
-      functions: [],
-      macros: [],
-      macro_aliases: [],
-      context_modules: [],
-      vars: [],
-      export_vars: nil,
-      lexical_tracker: nil}
+  def __access__(caller, args) do
+    Record.access(caller, __MODULE__, __record__(:fields), args)
  end

-  def __struct__(kv) do
-    Enum.reduce kv, __struct__(), fn {k, v}, acc -> :maps.update(k, v, acc) end
+  def __record__(kind, _), do: __record__(kind)
+  def __record__(:name),   do: Macro.Env
+
+  # When adding removing new fields,
+  # src/elixir_tree_helpers.erl needs to be changed as well.
+  def __record__(:fields) do
+    [
+      {:module,nil},
+      {:file,nil},
+      {:line,nil},
+      {:function,nil},
+      {:aliases,nil},
+      {:context,nil},
+      {:requires,nil},
+      {:macros,nil}
+    ]
  end

  @doc """
-  Returns a keyword list containing the file and line
-  information as keys.
+  Returns the current module name.
  """
-  @spec location(t) :: Keyword.t
-  def location(env)
-  def location(%{__struct__: Macro.Env, file: file, line: line}) do
-    [file: file, line: line]
-  end
+  def module(record),  do: elem(record, 2)

  @doc """
-  Returns whether the compilation environment is currently
+  Returns the current file name as a binary.
+  """
+  def file(record),    do: elem(record, 3)
+
+  @doc """
+  Returns the current line as an integer.
+  """
+  def line(record),    do: elem(record, 4)
+
+  @doc """
+  Returns a tuple as { Atom, Integer }, where the first element
+  is the function name and the seconds its arity. Returns `nil`
+  if not inside a function.
+  """
+  def function(record), do: elem(record, 5)
+
+  @doc """
+  Returns a list of two item tuples, where the first
+  item is the aliased name and the second the actual name.
+  """
+  def aliases(record), do: elem(record, 6)
+
+  @doc """
+  Returns wether the compilation environment is currently
  inside a guard.
  """
-  @spec in_guard?(t) :: boolean
-  def in_guard?(env)
-  def in_guard?(%{__struct__: Macro.Env, context: context}), do: context == :guard
+  def in_guard?(record), do: elem(record, 7) == :guard

  @doc """
-  Returns whether the compilation environment is currently
+  Returns wether the compilation environment is currently
  inside a match clause.
  """
-  @spec in_match?(t) :: boolean
-  def in_match?(env)
-  def in_match?(%{__struct__: Macro.Env, context: context}), do: context == :match
+  def in_match?(record), do: elem(record, 7) == :assign

  @doc """
-  Returns the environment stacktrace.
+  Returns the list of required modules.
  """
-  @spec stacktrace(t) :: list
-  def stacktrace(%{__struct__: Macro.Env} = env) do
-    cond do
-      is_nil(env.module) ->
-        [{:elixir_compiler, :__FILE__, 1, relative_location(env)}]
-      is_nil(env.function) ->
-        [{env.module, :__MODULE__, 0, relative_location(env)}]
-      true ->
-        {name, arity} = env.function
-        [{env.module, name, arity, relative_location(env)}]
-    end
-  end
+  def requires(record), do: elem(record, 8)

-  defp relative_location(env) do
-    [file: Path.relative_to_cwd(env.file), line: env.line]
+  @doc """
+  Returns a list of macros imported from each module.
+  """
+  def macros(record), do: elem(record, 9)
+
+  @doc """
+  Returns a keywords list containing the file and line
+  information as keys.
+  """
+  def location(record) do
+    [file: file(record), line: line(record)]
  end
-end
+end
@@ -1,801 +0,0 @@
-defmodule Map do
-  @moduledoc """
-  A set of functions for working with maps.
-
-  Maps are the "go to" key-value data structure in Elixir. Maps can be created
-  with the `%{}` syntax, and key-value pairs can be expressed as `key => value`:
-
-      iex> %{}
-      %{}
-      iex> %{"one" => :two, 3 => "four"}
-      %{3 => "four", "one" => :two}
-
-  Key-value pairs in a map do not follow any order (that's why the printed map
-  in the example above has a different order than the map that was created).
-
-  Maps do not impose any restriction on the key type: anything can be a key in a
-  map. As a key-value structure, maps do not allow duplicated keys; keys are
-  compared using the exact-equality operator (`===`). If colliding keys are defined
-  in a map literal, the last one prevails.
-
-  When the key in a key-value pair is an atom, the `key: value` shorthand syntax
-  can be used (as in many other special forms), provided key-value pairs are put at
-  the end:
-
-      iex> %{"hello" => "world", a: 1, b: 2}
-      %{:a => 1, :b => 2, "hello" => "world"}
-
-  Keys in maps can be accessed through some of the functions in this module
-  (such as `Map.get/3` or `Map.fetch/2`) or through the `[]` syntax provided by
-  the `Access` module:
-
-      iex> map = %{a: 1, b: 2}
-      iex> Map.fetch(map, :a)
-      {:ok, 1}
-      iex> map[:b]
-      2
-      iex> map["non_existing_key"]
-      nil
-
-  The alternative access syntax `map.key` is provided alongside `[]` when the
-  map has a `:key` key; note that while `map[key]` will return `nil` if `map`
-  doesn't contain the key `key`, `map.key` will raise if `map` doesn't contain
-  the key `:key`.
-
-      iex> map = %{foo: "bar", baz: "bong"}
-      iex> map.foo
-      "bar"
-      iex> map.non_existing_key
-      ** (KeyError) key :non_existing_key not found in: %{baz: "bong", foo: "bar"}
-
-  Maps can be pattern matched on; when a map is on the left-hand side of a
-  pattern match, it will match if the map on the right-hand side contains the
-  keys on the left-hand side and their values match the ones on the left-hand
-  side. This means that an empty map matches every map.
-
-      iex> %{} = %{foo: "bar"}
-      %{foo: "bar"}
-      iex> %{a: a} = %{:a => 1, "b" => 2, [:c, :e, :e] => 3}
-      iex> a
-      1
-      iex> %{:c => 3} = %{:a => 1, 2 => :b}
-      ** (MatchError) no match of right hand side value: %{2 => :b, :a => 1}
-
-  Variables can be used as map keys both when writing map literals as well as
-  when matching:
-
-      iex> n = 1
-      1
-      iex> %{n => :one}
-      %{1 => :one}
-      iex> %{^n => :one} = %{1 => :one, 2 => :two, 3 => :three}
-      %{1 => :one, 2 => :two, 3 => :three}
-
-  Maps also support a specific update syntax to update the value stored under
-  *existing* atom keys:
-
-      iex> map = %{one: 1, two: 2}
-      iex> %{map | one: "one"}
-      %{one: "one", two: 2}
-      iex> %{map | three: 3}
-      ** (KeyError) key :three not found
-
-  ## Modules to work with maps
-
-  This module aims to provide functions that perform operations specific to maps
-  (like accessing keys, updating values, and so on). For traversing maps as
-  collections, developers should use the `Enum` module that works across a
-  variety of data types.
-
-  The `Kernel` module also provides a few functions to work with maps: for
-  example, `Kernel.map_size/1` to know the number of key-value pairs in a map or
-  `Kernel.is_map/1` to know if a term is a map.
-  """
-
-  @type key :: any
-  @type value :: any
-  @compile {:inline, fetch: 2, put: 3, delete: 2, has_key?: 2}
-
-  @doc """
-  Returns all keys from `map`.
-
-  ## Examples
-
-      iex> Map.keys(%{a: 1, b: 2})
-      [:a, :b]
-
-  """
-  @spec keys(map) :: [key]
-  defdelegate keys(map), to: :maps
-
-  @doc """
-  Returns all values from `map`.
-
-  ## Examples
-
-      iex> Map.values(%{a: 1, b: 2})
-      [1, 2]
-
-  """
-  @spec values(map) :: [value]
-  defdelegate values(map), to: :maps
-
-  @doc """
-  Converts `map` to a list.
-
-  Each key-value pair in the map is converted to a two-element tuple `{key,
-  value}` in the resulting list.
-
-  ## Examples
-
-      iex> Map.to_list(%{a: 1})
-      [a: 1]
-      iex> Map.to_list(%{1 => 2})
-      [{1, 2}]
-
-  """
-  @spec to_list(map) :: [{term, term}]
-  defdelegate to_list(map), to: :maps
-
-  @doc """
-  Returns a new empty map.
-
-  ## Examples
-
-      iex> Map.new
-      %{}
-
-  """
-  @spec new :: map
-  def new, do: %{}
-
-  @doc """
-  Creates a map from an `enumerable`.
-
-  Duplicated keys are removed; the latest one prevails.
-
-  ## Examples
-
-      iex> Map.new([{:b, 1}, {:a, 2}])
-      %{a: 2, b: 1}
-      iex> Map.new([a: 1, a: 2, a: 3])
-      %{a: 3}
-
-  """
-  @spec new(Enumerable.t) :: map
-  def new(enumerable)
-  def new(%{__struct__: _} = struct), do: new_from_enum(struct)
-  def new(%{} = map), do: map
-  def new(enum), do: new_from_enum(enum)
-
-  defp new_from_enum(enumerable) do
-    enumerable
-    |> Enum.to_list
-    |> :maps.from_list
-  end
-
-  @doc """
-  Creates a map from an `enumerable` via the given transformation function.
-
-  Duplicated keys are removed; the latest one prevails.
-
-  ## Examples
-
-      iex> Map.new([:a, :b], fn x -> {x, x} end)
-      %{a: :a, b: :b}
-
-  """
-  @spec new(Enumerable.t, (term -> {key, value})) :: map
-  def new(enumerable, transform) when is_function(transform, 1) do
-    enumerable
-    |> Enum.to_list
-    |> new_transform(transform, [])
-  end
-
-  defp new_transform([], _fun, acc) do
-    acc
-    |> :lists.reverse
-    |> :maps.from_list
-  end
-
-  defp new_transform([item | rest], fun, acc) do
-    new_transform(rest, fun, [fun.(item) | acc])
-  end
-
-  @doc """
-  Returns whether the given `key` exists in the given `map`.
-
-  ## Examples
-
-      iex> Map.has_key?(%{a: 1}, :a)
-      true
-      iex> Map.has_key?(%{a: 1}, :b)
-      false
-
-  """
-  @spec has_key?(map, key) :: boolean
-  def has_key?(map, key), do: :maps.is_key(key, map)
-
-  @doc """
-  Fetches the value for a specific `key` in the given `map`.
-
-  If `map` contains the given `key` with value `value`, then `{:ok, value}` is
-  returned. If `map` doesn't contain `key`, `:error` is returned.
-
-  ## Examples
-
-      iex> Map.fetch(%{a: 1}, :a)
-      {:ok, 1}
-      iex> Map.fetch(%{a: 1}, :b)
-      :error
-
-  """
-  @spec fetch(map, key) :: {:ok, value} | :error
-  def fetch(map, key), do: :maps.find(key, map)
-
-  @doc """
-  Fetches the value for a specific `key` in the given `map`, erroring out if
-  `map` doesn't contain `key`.
-
-  If `map` contains the given `key`, the corresponding value is returned. If
-  `map` doesn't contain `key`, a `KeyError` exception is raised.
-
-  ## Examples
-
-      iex> Map.fetch!(%{a: 1}, :a)
-      1
-      iex> Map.fetch!(%{a: 1}, :b)
-      ** (KeyError) key :b not found in: %{a: 1}
-
-  """
-  @spec fetch!(map, key) :: value | no_return
-  def fetch!(map, key) do
-    case fetch(map, key) do
-      {:ok, value} -> value
-      :error -> raise KeyError, key: key, term: map
-    end
-  end
-
-  @doc """
-  Puts the given `value` under `key` unless the entry `key`
-  already exists in `map`.
-
-  ## Examples
-
-      iex> Map.put_new(%{a: 1}, :b, 2)
-      %{b: 2, a: 1}
-      iex> Map.put_new(%{a: 1, b: 2}, :a, 3)
-      %{a: 1, b: 2}
-
-  """
-  @spec put_new(map, key, value) :: map
-  def put_new(map, key, value) do
-    case has_key?(map, key) do
-      true  -> map
-      false -> put(map, key, value)
-    end
-  end
-
-  @doc """
-  Evaluates `fun` and puts the result under `key`
-  in `map` unless `key` is already present.
-
-  This function is useful in case you want to compute the value to put under
-  `key` only if `key` is not already present (e.g., the value is expensive to
-  calculate or generally difficult to setup and teardown again).
-
-  ## Examples
-
-      iex> map = %{a: 1}
-      iex> fun = fn ->
-      ...>   # some expensive operation here
-      ...>   3
-      ...> end
-      iex> Map.put_new_lazy(map, :a, fun)
-      %{a: 1}
-      iex> Map.put_new_lazy(map, :b, fun)
-      %{a: 1, b: 3}
-
-  """
-  @spec put_new_lazy(map, key, (() -> value)) :: map
-  def put_new_lazy(map, key, fun) when is_function(fun, 0) do
-    case has_key?(map, key) do
-      true  -> map
-      false -> put(map, key, fun.())
-    end
-  end
-
-  @doc """
-  Returns a new map with all the key-value pairs in `map` where the key
-  is in `keys`.
-
-  If `keys` contains keys that are not in `map`, they're simply ignored.
-
-  ## Examples
-
-      iex> Map.take(%{a: 1, b: 2, c: 3}, [:a, :c, :e])
-      %{a: 1, c: 3}
-
-  """
-  @spec take(map, Enumerable.t) :: map
-  def take(map, keys)
-
-  def take(map, keys) when is_map(map) do
-    keys
-    |> Enum.to_list
-    |> do_take(map, [])
-  end
-
-  def take(non_map, _keys) do
-    :erlang.error({:badmap, non_map})
-  end
-
-  defp do_take([], _map, acc), do: :maps.from_list(acc)
-  defp do_take([key | rest], map, acc) do
-    acc = case fetch(map, key) do
-      {:ok, value} -> [{key, value} | acc]
-      :error -> acc
-    end
-    do_take(rest, map, acc)
-  end
-
-  @doc """
-  Gets the value for a specific `key` in `map`.
-
-  If `key` is present in `map` with value `value`, then `value` is
-  returned. Otherwise, `default` is returned (which is `nil` unless
-  specified otherwise).
-
-  ## Examples
-
-      iex> Map.get(%{}, :a)
-      nil
-      iex> Map.get(%{a: 1}, :a)
-      1
-      iex> Map.get(%{a: 1}, :b)
-      nil
-      iex> Map.get(%{a: 1}, :b, 3)
-      3
-
-  """
-  @spec get(map, key) :: value
-  @spec get(map, key, value) :: value
-  def get(map, key, default \\ nil) do
-    case fetch(map, key) do
-      {:ok, value} -> value
-      :error -> default
-    end
-  end
-
-  @doc """
-  Gets the value for a specific `key` in `map`.
-
-  If `key` is present in `map` with value `value`, then `value` is
-  returned. Otherwise, `fun` is evaluated and its result is returned.
-
-  This is useful if the default value is very expensive to calculate or
-  generally difficult to setup and teardown again.
-
-  ## Examples
-
-      iex> map = %{a: 1}
-      iex> fun = fn ->
-      ...>   # some expensive operation here
-      ...>   13
-      ...> end
-      iex> Map.get_lazy(map, :a, fun)
-      1
-      iex> Map.get_lazy(map, :b, fun)
-      13
-
-  """
-  @spec get_lazy(map, key, (() -> value)) :: value
-  def get_lazy(map, key, fun) when is_function(fun, 0) do
-    case fetch(map, key) do
-      {:ok, value} -> value
-      :error -> fun.()
-    end
-  end
-
-  @doc """
-  Puts the given `value` under `key` in `map`.
-
-  ## Examples
-
-      iex> Map.put(%{a: 1}, :b, 2)
-      %{a: 1, b: 2}
-      iex> Map.put(%{a: 1, b: 2}, :a, 3)
-      %{a: 3, b: 2}
-
-  """
-  @spec put(map, key, value) :: map
-  def put(map, key, value) do
-    :maps.put(key, value, map)
-  end
-
-  @doc """
-  Deletes the entry in `map` for a specific `key`.
-
-  If the `key` does not exist, returns `map` unchanged.
-
-  ## Examples
-
-      iex> Map.delete(%{a: 1, b: 2}, :a)
-      %{b: 2}
-      iex> Map.delete(%{b: 2}, :a)
-      %{b: 2}
-
-  """
-  @spec delete(map, key) :: map
-  def delete(map, key), do: :maps.remove(key, map)
-
-  @doc """
-  Merges two maps into one.
-
-  All keys in `map2` will be added to `map1`, overriding any existing one
-  (i.e., the keys in `map2` "have precedence" over the ones in `map1`).
-
-  If you have a struct and you would like to merge a set of keys into the
-  struct, do not use this function, as it would merge all keys on the right
-  side into the struct, even if the key is not part of the struct. Instead,
-  use `Kernel.struct/2`.
-
-  ## Examples
-
-      iex> Map.merge(%{a: 1, b: 2}, %{a: 3, d: 4})
-      %{a: 3, b: 2, d: 4}
-
-  """
-  @spec merge(map, map) :: map
-  defdelegate merge(map1, map2), to: :maps
-
-  @doc """
-  Merges two maps into one, resolving conflicts through the given `callback`.
-
-  All keys in `map2` will be added to `map1`. The given function will be invoked
-  when there are duplicate keys; its arguments are `key` (the duplicate key),
-  `value1` (the value of `key` in `map1`), and `value2` (the value of `key` in
-  `map2`). The value returned by `callback` is used as the value under `key` in
-  the resulting map.
-
-  ## Examples
-
-      iex> Map.merge(%{a: 1, b: 2}, %{a: 3, d: 4}, fn _k, v1, v2 ->
-      ...>   v1 + v2
-      ...> end)
-      %{a: 4, b: 2, d: 4}
-
-  """
-  @spec merge(map, map, (key, value, value -> value)) :: map
-  def merge(map1, map2, callback) when is_function(callback, 3) do
-    :maps.fold fn k, v2, acc ->
-      update(acc, k, v2, fn(v1) -> callback.(k, v1, v2) end)
-    end, map1, map2
-  end
-
-  @doc """
-  Updates the `key` in `map` with the given function.
-
-  If `key` is present in `map` with value `value`, `fun` is invoked with
-  argument `value` and its result is used as the new value of `key`. If `key` is
-  not present in `map`, `initial` is inserted as the value of `key`.
-
-  ## Examples
-
-      iex> Map.update(%{a: 1}, :a, 13, &(&1 * 2))
-      %{a: 2}
-      iex> Map.update(%{a: 1}, :b, 11, &(&1 * 2))
-      %{a: 1, b: 11}
-
-  """
-  @spec update(map, key, value, (value -> value)) :: map
-  def update(map, key, initial, fun) when is_function(fun, 1) do
-    case fetch(map, key) do
-      {:ok, value} ->
-        put(map, key, fun.(value))
-      :error ->
-        put(map, key, initial)
-    end
-  end
-
-  @doc """
-  Returns and removes the value associated with `key` in `map`.
-
-  If `key` is present in `map` with value `value`, `{value, new_map}` is
-  returned where `new_map` is the result of removing `key` from `map`. If `key`
-  is not present in `map`, `{default, map}` is returned.
-
-  ## Examples
-
-      iex> Map.pop(%{a: 1}, :a)
-      {1, %{}}
-      iex> Map.pop(%{a: 1}, :b)
-      {nil, %{a: 1}}
-      iex> Map.pop(%{a: 1}, :b, 3)
-      {3, %{a: 1}}
-
-  """
-  @spec pop(map, key, value) :: {value, map}
-  def pop(map, key, default \\ nil) do
-    case map do
-      %{^key => value} -> {value, delete(map, key)}
-      %{} -> {default, map}
-    end
-  end
-
-  @doc """
-  Lazily returns and removes the value associated with `key` in `map`.
-
-  If `key` is present in `map` with value `value`, `{value, new_map}` is
-  returned where `new_map` is the result of removing `key` from `map`. If `key`
-  is not present in `map`, `{fun_result, map}` is returned, where `fun_result`
-  is the result of applying `fun`.
-
-  This is useful if the default value is very expensive to calculate or
-  generally difficult to setup and teardown again.
-
-  ## Examples
-
-      iex> map = %{a: 1}
-      iex> fun = fn ->
-      ...>   # some expensive operation here
-      ...>   13
-      ...> end
-      iex> Map.pop_lazy(map, :a, fun)
-      {1, %{}}
-      iex> Map.pop_lazy(map, :b, fun)
-      {13, %{a: 1}}
-
-  """
-  @spec pop_lazy(map, key, (() -> value)) :: {value, map}
-  def pop_lazy(map, key, fun) when is_function(fun, 0) do
-    case fetch(map, key) do
-      {:ok, value} -> {value, delete(map, key)}
-      :error -> {fun.(), map}
-    end
-  end
-
-  @doc """
-  Drops the given `keys` from `map`.
-
-  If `keys` contains keys that are not in `map`, they're simply ignored.
-
-  ## Examples
-
-      iex> Map.drop(%{a: 1, b: 2, c: 3}, [:b, :d])
-      %{a: 1, c: 3}
-
-  """
-  @spec drop(map, Enumerable.t) :: map
-  def drop(map, keys)
-
-  def drop(map, keys) when is_map(map) do
-    keys
-    |> Enum.to_list
-    |> drop_list(map)
-  end
-
-  def drop(non_map, _keys) do
-    :erlang.error({:badmap, non_map})
-  end
-
-  defp drop_list([], acc), do: acc
-  defp drop_list([key | rest], acc) do
-    drop_list(rest, delete(acc, key))
-  end
-
-  @doc """
-  Takes all entries corresponding to the given `keys` in `maps` and extracts
-  them into a separate map.
-
-  Returns a tuple with the new map and the old map with removed keys.
-
-  Keys for which there are no entries in `map` are ignored.
-
-  ## Examples
-
-      iex> Map.split(%{a: 1, b: 2, c: 3}, [:a, :c, :e])
-      {%{a: 1, c: 3}, %{b: 2}}
-
-  """
-  @spec split(map, Enumerable.t) :: {map, map}
-  def split(map, keys)
-
-  def split(map, keys) when is_map(map) do
-    keys
-    |> Enum.to_list
-    |> do_split([], map)
-  end
-
-  def split(non_map, _keys) do
-    :erlang.error({:badmap, non_map})
-  end
-
-  defp do_split([], inc, exc) do
-    {:maps.from_list(inc), exc}
-  end
-  defp do_split([key | rest], inc, exc) do
-    case fetch(exc, key) do
-      {:ok, value} ->
-        do_split(rest, [{key, value} | inc], delete(exc, key))
-      :error ->
-        do_split(rest, inc, exc)
-    end
-  end
-
-  @doc """
-  Updates `key` with the given function.
-
-  If `key` is present in `map` with value `value`, `fun` is invoked with
-  argument `value` and its result is used as the new value of `key`. If `key` is
-  not present in `map`, a `KeyError` exception is raised.
-
-  ## Examples
-
-      iex> Map.update!(%{a: 1}, :a, &(&1 * 2))
-      %{a: 2}
-
-      iex> Map.update!(%{a: 1}, :b, &(&1 * 2))
-      ** (KeyError) key :b not found in: %{a: 1}
-
-  """
-  @spec update!(map, key, (value -> value)) :: map | no_return
-  def update!(%{} = map, key, fun) when is_function(fun, 1) do
-    case fetch(map, key) do
-      {:ok, value} ->
-        put(map, key, fun.(value))
-      :error ->
-        raise KeyError, term: map, key: key
-    end
-  end
-
-  def update!(map, _key, _fun), do: :erlang.error({:badmap, map})
-
-  @doc """
-  Gets the value from `key` and updates it, all in one pass.
-
-  `fun` is called with the current value under `key` in `map` (or `nil` if `key`
-  is not present in `map`) and must return a two-element tuple: the "get" value
-  (the retrieved value, which can be operated on before being returned) and the
-  new value to be stored under `key` in the resulting new map. `fun` may also
-  return `:pop`, which means the current value shall be removed from `map` and
-  returned (making this function behave like `Map.pop(map, key)`.
-
-  The returned value is a tuple with the "get" value returned by
-  `fun` and a new map with the updated value under `key`.
-
-  ## Examples
-
-      iex> Map.get_and_update(%{a: 1}, :a, fn current_value ->
-      ...>   {current_value, "new value!"}
-      ...> end)
-      {1, %{a: "new value!"}}
-
-      iex> Map.get_and_update(%{a: 1}, :b, fn current_value ->
-      ...>   {current_value, "new value!"}
-      ...> end)
-      {nil, %{b: "new value!", a: 1}}
-
-      iex> Map.get_and_update(%{a: 1}, :a, fn _ -> :pop end)
-      {1, %{}}
-
-      iex> Map.get_and_update(%{a: 1}, :b, fn _ -> :pop end)
-      {nil, %{a: 1}}
-
-  """
-  @spec get_and_update(map, key, (value -> {get, value} | :pop)) :: {get, map} when get: term
-  def get_and_update(%{} = map, key, fun) when is_function(fun, 1) do
-    current =
-      case :maps.find(key, map) do
-        {:ok, value} -> value
-        :error -> nil
-      end
-
-    case fun.(current) do
-      {get, update} ->
-        {get, :maps.put(key, update, map)}
-      :pop ->
-        {current, :maps.remove(key, map)}
-      other ->
-        raise "the given function must return a two-element tuple or :pop, got: #{inspect(other)}"
-    end
-  end
-
-  def get_and_update(map, _key, _fun), do: :erlang.error({:badmap, map})
-
-  @doc """
-  Gets the value from `key` and updates it. Raises if there is no `key`.
-
-  Behaves exactly like `get_and_update/3`, but raises a `KeyError` exception if
-  `key` is not present in `map`.
-
-  ## Examples
-
-      iex> Map.get_and_update!(%{a: 1}, :a, fn current_value ->
-      ...>   {current_value, "new value!"}
-      ...> end)
-      {1, %{a: "new value!"}}
-
-      iex> Map.get_and_update!(%{a: 1}, :b, fn current_value ->
-      ...>   {current_value, "new value!"}
-      ...> end)
-      ** (KeyError) key :b not found in: %{a: 1}
-
-      iex> Map.get_and_update!(%{a: 1}, :a, fn _ ->
-      ...>   :pop
-      ...> end)
-      {1, %{}}
-
-  """
-  @spec get_and_update!(map, key, (value -> {get, value})) :: {get, map} | no_return when get: term
-  def get_and_update!(%{} = map, key, fun) when is_function(fun, 1) do
-    case :maps.find(key, map) do
-      {:ok, value} ->
-        case fun.(value) do
-          {get, update} ->
-            {get, :maps.put(key, update, map)}
-          :pop ->
-            {value, :maps.remove(key, map)}
-          other ->
-            raise "the given function must return a two-element tuple or :pop, got: #{inspect(other)}"
-        end
-      :error ->
-        raise KeyError, term: map, key: key
-    end
-  end
-
-  def get_and_update!(map, _key, _fun), do: :erlang.error({:badmap, map})
-
-  @doc """
-  Converts a `struct` to map.
-
-  It accepts the struct module or a struct itself and
-  simply removes the `__struct__` field from the given struct
-  or from a new struct generated from the given module.
-
-  ## Example
-
-      defmodule User do
-        defstruct [:name]
-      end
-
-      Map.from_struct(User)
-      #=> %{name: nil}
-
-      Map.from_struct(%User{name: "john"})
-      #=> %{name: "john"}
-
-  """
-  @spec from_struct(atom | struct) :: map
-  def from_struct(struct) when is_atom(struct) do
-    :maps.remove(:__struct__, struct.__struct__)
-  end
-
-  def from_struct(%{__struct__: _} = struct) do
-    :maps.remove(:__struct__, struct)
-  end
-
-  @doc """
-  Checks if two maps are equal.
-
-  Two maps are considered to be equal if they contain
-  the same keys and those keys contain the same values.
-
-  ## Examples
-
-      iex> Map.equal?(%{a: 1, b: 2}, %{b: 2, a: 1})
-      true
-      iex> Map.equal?(%{a: 1, b: 2}, %{b: 1, a: 2})
-      false
-
-  """
-  @spec equal?(map, map) :: boolean
-  def equal?(%{} = map1, %{} = map2), do: map1 === map2
-
-  @doc false
-  # TODO: Remove on 2.0
-  def size(map) do
-    IO.warn "Map.size/1 is deprecated, please use Kernel.map_size/1"
-    map_size(map)
-  end
-end
@@ -1,370 +0,0 @@
-defmodule MapSet do
-  @moduledoc """
-  Functions that work on sets.
-
-  `MapSet` is the "go to" set data structure in Elixir. A set can be constructed
-  using `MapSet.new/0`:
-
-      iex> MapSet.new
-      #MapSet<[]>
-
-  A set can contain any kind of elements and elements in a set don't have to be
-  of the same type. By definition, sets can't contain duplicate elements: when
-  inserting an element in a set where it's already present, the insertion is
-  simply a no-op.
-
-      iex> set = MapSet.new
-      iex> MapSet.put(set, "foo")
-      #MapSet<["foo"]>
-      iex> set |> MapSet.put("foo") |> MapSet.put("foo")
-      #MapSet<["foo"]>
-
-  A `MapSet` is represented internally using the `%MapSet{}` struct. This struct
-  can be used whenever there's a need to pattern match on something being a `MapSet`:
-
-      iex> match?(%MapSet{}, MapSet.new())
-      true
-
-  Note that, however, the struct fields are private and must not be accessed
-  directly; use the functions in this module to perform operations on sets.
-
-  Sets can also be constructed starting from other collection-type data
-  structures: for example, see `MapSet.new/1` or `Enum.into/2`.
-  """
-
-  @type value :: term
-
-  @opaque t(value) :: %__MODULE__{map: %{optional(value) => true}}
-  @type t :: t(term)
-
-  defstruct map: %{}
-
-  @doc """
-  Returns a new set.
-
-  ## Examples
-
-      iex> MapSet.new
-      #MapSet<[]>
-
-  """
-  @spec new :: t
-  def new(), do: %MapSet{}
-
-  @doc """
-  Creates a set from an enumerable.
-
-  ## Examples
-
-      iex> MapSet.new([:b, :a, 3])
-      #MapSet<[3, :a, :b]>
-      iex> MapSet.new([3, 3, 3, 2, 2, 1])
-      #MapSet<[1, 2, 3]>
-
-  """
-  @spec new(Enum.t) :: t
-  def new(%__MODULE__{} = mapset), do: mapset
-  def new(enumerable) do
-    map =
-      enumerable
-      |> Enum.to_list
-      |> do_new([])
-
-    %MapSet{map: map}
-  end
-
-  @doc """
-  Creates a mapset from an enumerable via the transformation function.
-
-  ## Examples
-
-      iex> MapSet.new([1, 2, 1], fn x -> 2 * x end)
-      #MapSet<[2, 4]>
-
-  """
-  @spec new(Enum.t, (term -> val)) :: t(val) when val: value
-  def new(enumerable, transform) when is_function(transform, 1) do
-    map =
-      enumerable
-      |> Enum.to_list
-      |> do_new_transform(transform, [])
-
-    %MapSet{map: map}
-  end
-
-  defp do_new([], acc) do
-    :maps.from_list(acc)
-  end
-  defp do_new([item | rest], acc) do
-    do_new(rest, [{item, true} | acc])
-  end
-
-  defp do_new_transform([], _fun, acc) do
-    :maps.from_list(acc)
-  end
-  defp do_new_transform([item | rest], fun, acc) do
-    do_new_transform(rest, fun, [{fun.(item), true} | acc])
-  end
-
-  @doc """
-  Deletes `value` from `set`.
-
-  Returns a new set which is a copy of `set` but without `value`.
-
-  ## Examples
-
-      iex> set = MapSet.new([1, 2, 3])
-      iex> MapSet.delete(set, 4)
-      #MapSet<[1, 2, 3]>
-      iex> MapSet.delete(set, 2)
-      #MapSet<[1, 3]>
-
-  """
-  @spec delete(t(val1), val2) :: t(val1) when val1: value, val2: value
-  def delete(%MapSet{map: map} = set, value) do
-    %{set | map: Map.delete(map, value)}
-  end
-
-  @doc """
-  Returns a set that is `set1` without the members of `set2`.
-
-  ## Examples
-
-      iex> MapSet.difference(MapSet.new([1, 2]), MapSet.new([2, 3, 4]))
-      #MapSet<[1]>
-
-  """
-  @spec difference(t(val1), t(val2)) :: t(val1) when val1: value, val2: value
-  def difference(mapset1, mapset2)
-
-  # If the first set is less than twice the size of the second map,
-  # it is fastest to re-accumulate items in the first set that are not
-  # present in the second set.
-  def difference(%MapSet{map: map1}, %MapSet{map: map2})
-      when map_size(map1) < map_size(map2) * 2 do
-    map = map1
-    |> Map.keys
-    |> filter_not_in(map2)
-
-    %MapSet{map: map}
-  end
-
-  # If the second set is less than half the size of the first set, it's fastest
-  # to simply iterate through each item in the second set, deleting them from
-  # the first set.
-  def difference(%MapSet{map: map1}, %MapSet{map: map2}) do
-    %MapSet{map: Map.drop(map1, Map.keys(map2))}
-  end
-
-  defp filter_not_in(keys, map2, acc \\ [])
-  defp filter_not_in([], _map2, acc), do: :maps.from_list(acc)
-  defp filter_not_in([key | rest], map2, acc) do
-    acc = if Map.has_key?(map2, key) do
-      acc
-    else
-      [{key, true} | acc]
-    end
-    filter_not_in(rest, map2, acc)
-  end
-
-  @doc """
-  Checks if `set1` and `set2` have no members in common.
-
-  ## Examples
-
-      iex> MapSet.disjoint?(MapSet.new([1, 2]), MapSet.new([3, 4]))
-      true
-      iex> MapSet.disjoint?(MapSet.new([1, 2]), MapSet.new([2, 3]))
-      false
-
-  """
-  @spec disjoint?(t, t) :: boolean
-  def disjoint?(%MapSet{map: map1}, %MapSet{map: map2}) do
-    {map1, map2} = order_by_size(map1, map2)
-
-    map1
-    |> Map.keys
-    |> none_in?(map2)
-  end
-
-  defp none_in?([], _) do
-    true
-  end
-  defp none_in?([key | rest], map2) do
-    case Map.has_key?(map2, key) do
-      true -> false
-      false -> none_in?(rest, map2)
-    end
-  end
-
-  @doc """
-  Checks if two sets are equal.
-
-  The comparison between elements must be done using `===`.
-
-  ## Examples
-
-      iex> MapSet.equal?(MapSet.new([1, 2]), MapSet.new([2, 1, 1]))
-      true
-      iex> MapSet.equal?(MapSet.new([1, 2]), MapSet.new([3, 4]))
-      false
-
-  """
-  @spec equal?(t, t) :: boolean
-  def equal?(%MapSet{map: map1}, %MapSet{map: map2}) do
-    Map.equal?(map1, map2)
-  end
-
-  @doc """
-  Returns a set containing only members that `set1` and `set2` have in common.
-
-  ## Examples
-
-      iex> MapSet.intersection(MapSet.new([1, 2]), MapSet.new([2, 3, 4]))
-      #MapSet<[2]>
-
-      iex> MapSet.intersection(MapSet.new([1, 2]), MapSet.new([3, 4]))
-      #MapSet<[]>
-
-  """
-  @spec intersection(t(val), t(val)) :: t(val) when val: value
-  def intersection(%MapSet{map: map1}, %MapSet{map: map2}) do
-    {map1, map2} = order_by_size(map1, map2)
-
-    %MapSet{map: Map.take(map2, Map.keys(map1))}
-  end
-
-  @doc """
-  Checks if `set` contains `value`.
-
-  ## Examples
-
-      iex> MapSet.member?(MapSet.new([1, 2, 3]), 2)
-      true
-      iex> MapSet.member?(MapSet.new([1, 2, 3]), 4)
-      false
-
-  """
-  @spec member?(t, value) :: boolean
-  def member?(%MapSet{map: map}, value) do
-    Map.has_key?(map, value)
-  end
-
-  @doc """
-  Inserts `value` into `set` if `set` doesn't already contain it.
-
-  ## Examples
-
-      iex> MapSet.put(MapSet.new([1, 2, 3]), 3)
-      #MapSet<[1, 2, 3]>
-      iex> MapSet.put(MapSet.new([1, 2, 3]), 4)
-      #MapSet<[1, 2, 3, 4]>
-
-  """
-  @spec put(t(val), new_val) :: t(val | new_val) when val: value, new_val: value
-  def put(%MapSet{map: map} = set, value) do
-    %{set | map: Map.put(map, value, true)}
-  end
-
-  @doc """
-  Returns the number of elements in `set`.
-
-  ## Examples
-
-      iex> MapSet.size(MapSet.new([1, 2, 3]))
-      3
-
-  """
-  @spec size(t) :: non_neg_integer
-  def size(%MapSet{map: map}) do
-    map_size(map)
-  end
-
-  @doc """
-  Checks if `set1`'s members are all contained in `set2`.
-
-  This function checks if `set1` is a subset of `set2`.
-
-  ## Examples
-
-      iex> MapSet.subset?(MapSet.new([1, 2]), MapSet.new([1, 2, 3]))
-      true
-      iex> MapSet.subset?(MapSet.new([1, 2, 3]), MapSet.new([1, 2]))
-      false
-
-  """
-  @spec subset?(t, t) :: boolean
-  def subset?(%MapSet{map: map1}, %MapSet{map: map2}) do
-    if map_size(map1) <= map_size(map2) do
-      map1
-      |> Map.keys
-      |> do_subset?(map2)
-    else
-      false
-    end
-  end
-
-  defp do_subset?([], _), do: true
-  defp do_subset?([key | rest], map2) do
-    if Map.has_key?(map2, key) do
-      do_subset?(rest, map2)
-    else
-      false
-    end
-  end
-
-  @doc """
-  Converts `set` to a list.
-
-  ## Examples
-
-      iex> MapSet.to_list(MapSet.new([1, 2, 3]))
-      [1, 2, 3]
-
-  """
-  @spec to_list(t(val)) :: [val] when val: value
-  def to_list(%MapSet{map: map}) do
-    Map.keys(map)
-  end
-
-  @doc """
-  Returns a set containing all members of `set1` and `set2`.
-
-  ## Examples
-
-      iex> MapSet.union(MapSet.new([1, 2]), MapSet.new([2, 3, 4]))
-      #MapSet<[1, 2, 3, 4]>
-
-  """
-  @spec union(t(val1), t(val2)) :: t(val1 | val2) when val1: value, val2: value
-  def union(%MapSet{map: map1}, %MapSet{map: map2}) do
-    %MapSet{map: Map.merge(map1, map2)}
-  end
-
-  defp order_by_size(map1, map2) when map_size(map1) > map_size(map2), do: {map2, map1}
-  defp order_by_size(map1, map2), do: {map1, map2}
-
-  defimpl Enumerable do
-    def reduce(set, acc, fun), do: Enumerable.List.reduce(MapSet.to_list(set), acc, fun)
-    def member?(set, val),     do: {:ok, MapSet.member?(set, val)}
-    def count(set),            do: {:ok, MapSet.size(set)}
-  end
-
-  defimpl Collectable do
-    def into(original) do
-      {original, fn
-        set, {:cont, x} -> MapSet.put(set, x)
-        set, :done -> set
-        _, :halt -> :ok
-      end}
-    end
-  end
-
-  defimpl Inspect do
-    import Inspect.Algebra
-
-    def inspect(set, opts) do
-      concat ["#MapSet<", Inspect.List.inspect(MapSet.to_list(set), opts), ">"]
-    end
-  end
-end
@@ -1,359 +0,0 @@
-# This is an Elixir module responsible for tracking
-# calls in order to extract Elixir modules' behaviour
-# during compilation time.
-#
-# ## Implementation
-#
-# The implementation uses the digraph module to track
-# all dependencies. The graph starts with one main vertex:
-#
-# * `:local` - points to local functions
-#
-# We can also have the following vertices:
-#
-# * `Module` - a module that was invoked via an import
-# * `{name, arity}` - a local function/arity pair
-# * `{:import, name, arity}` - an invoked function/arity import
-#
-# Each of those vertices can associate to other vertices
-# as described below:
-#
-# * `Module`
-#   * in neighbours:  `{:import, name, arity}`
-#
-# * `{name, arity}`
-#   * in neighbours: `:local`, `{name, arity}`
-#   * out neighbours: `{:import, name, arity}`
-#
-# * `{:import, name, arity}`
-#   * in neighbours: `{name, arity}`
-#   * out neighbours: `Module`
-#
-# Note that since this is required for bootstrap, we can't use
-# any of the `GenServer` conveniences.
-defmodule Module.LocalsTracker do
-  @moduledoc false
-
-  @timeout   30_000
-  @behaviour :gen_server
-
-  @type ref :: pid | module
-  @type name :: atom
-  @type name_arity :: {name, arity}
-
-  @type local :: {name, arity}
-  @type import :: {:import, name, arity}
-
-  # Public API
-
-  @doc """
-  Returns all imported modules that had the given
-  `{name, arity}` invoked.
-  """
-  @spec imports_with_dispatch(ref, name_arity) :: [module]
-  def imports_with_dispatch(ref, {name, arity}) do
-    d = :gen_server.call(to_pid(ref), :digraph, @timeout)
-    :digraph.out_neighbours(d, {:import, name, arity})
-  end
-
-  @doc """
-  Returns all locals that are reachable.
-
-  By default, all public functions are reachable.
-  A private function is only reachable if it has
-  a public function that it invokes directly.
-  """
-  @spec reachable(ref) :: [local]
-  def reachable(ref) do
-    reachable_from(:gen_server.call(to_pid(ref), :digraph, @timeout), :local)
-  end
-
-  defp reachable_from(d, starting) do
-    :sets.to_list(reduce_reachable(d, starting, :sets.new))
-  end
-
-  defp reduce_reachable(d, vertex, vertices) do
-    neighbours = :digraph.out_neighbours(d, vertex)
-    neighbours = (for {_, _} = t <- neighbours, do: t) |> :sets.from_list
-    remaining  = :sets.subtract(neighbours, vertices)
-    vertices   = :sets.union(neighbours, vertices)
-    :sets.fold(&reduce_reachable(d, &1, &2), vertices, remaining)
-  end
-
-  defp to_pid(pid) when is_pid(pid),  do: pid
-  defp to_pid(mod) when is_atom(mod) do
-    table = :elixir_module.data_table(mod)
-    :ets.lookup_element(table, {:elixir, :locals_tracker}, 2)
-  end
-
-  # Internal API
-
-  # Starts the tracker and returns its PID.
-  @doc false
-  def start_link do
-    :gen_server.start_link(__MODULE__, [], [])
-  end
-
-  # Adds a definition into the tracker. A public
-  # definition is connected with the :local node
-  # while a private one is left unreachable until
-  # a call is made to.
-  @doc false
-  def add_definition(pid, kind, tuple) when kind in [:def, :defp, :defmacro, :defmacrop] do
-    :gen_server.cast(pid, {:add_definition, kind, tuple})
-  end
-
-  # Adds and tracks defaults for a definition into the tracker.
-  @doc false
-  def add_defaults(pid, kind, tuple, defaults) when kind in [:def, :defp, :defmacro, :defmacrop] do
-    :gen_server.cast(pid, {:add_defaults, kind, tuple, defaults})
-  end
-
-  # Adds a local dispatch to the given target.
-  def add_local(pid, to) when is_tuple(to) do
-    :gen_server.cast(pid, {:add_local, :local, to})
-  end
-
-  # Adds a local dispatch from-to the given target.
-  @doc false
-  def add_local(pid, from, to) when is_tuple(from) and is_tuple(to) do
-    :gen_server.cast(pid, {:add_local, from, to})
-  end
-
-  # Adds an import dispatch to the given target.
-  @doc false
-  def add_import(pid, function, module, target) when is_atom(module) and is_tuple(target) do
-    :gen_server.cast(pid, {:add_import, function, module, target})
-  end
-
-  # Yanks a local node. Returns its in and out vertices in a tuple.
-  @doc false
-  def yank(pid, local) do
-    :gen_server.call(to_pid(pid), {:yank, local}, @timeout)
-  end
-
-  # Reattach a previously yanked node
-  @doc false
-  def reattach(pid, kind, tuple, neighbours) do
-    :gen_server.cast(to_pid(pid), {:reattach, kind, tuple, neighbours})
-  end
-
-  # Collecting all conflicting imports with the given functions
-  @doc false
-  def collect_imports_conflicts(pid, all_defined) do
-    d = :gen_server.call(pid, :digraph, @timeout)
-
-    for {name, arity} <- all_defined,
-        :digraph.in_neighbours(d, {:import, name, arity}) != [],
-        n = :digraph.out_neighbours(d, {:import, name, arity}),
-        n != [] do
-      {n, name, arity}
-    end
-  end
-
-  # Collect all unused definitions based on the private
-  # given also accounting the expected amount of default
-  # clauses a private function have.
-  @doc false
-  def collect_unused_locals(ref, private) do
-    d = :gen_server.call(to_pid(ref), :digraph, @timeout)
-    {unreachable(d, private), collect_warnings(d, private)}
-  end
-
-  defp unreachable(d, private) do
-    unreachable = for {tuple, _, _} <- private, do: tuple
-
-    private =
-      for {tuple, :defp, _} <- private do
-        neighbours = :digraph.in_neighbours(d, tuple)
-        neighbours = for {_, _} = t <- neighbours, do: t
-        {tuple, :sets.from_list(neighbours)}
-      end
-
-    reduce_unreachable(private, [], :sets.from_list(unreachable))
-  end
-
-  defp reduce_unreachable([{vertex, callers} | t], acc, unreachable) do
-    if :sets.is_subset(callers, unreachable) do
-      reduce_unreachable(t, [{vertex, callers} | acc], unreachable)
-    else
-      reduce_unreachable(acc ++ t, [], :sets.del_element(vertex, unreachable))
-    end
-  end
-
-  defp reduce_unreachable([], _acc, unreachable) do
-    :sets.to_list(unreachable)
-  end
-
-  defp collect_warnings(d, private) do
-    reachable = reachable_from(d, :local)
-    :lists.foldl(&collect_warnings(&1, &2, reachable), [], private)
-  end
-
-  defp collect_warnings({tuple, kind, 0}, acc, reachable) do
-    if :lists.member(tuple, reachable) do
-      acc
-    else
-      [{:unused_def, tuple, kind} | acc]
-    end
-  end
-
-  defp collect_warnings({tuple, kind, default}, acc, reachable) when default > 0 do
-    {name, arity} = tuple
-    min = arity - default
-    max = arity
-
-    invoked = for {n, a} <- reachable, n == name, a in min..max, do: a
-
-    if invoked == [] do
-      [{:unused_def, tuple, kind} | acc]
-    else
-      case :lists.min(invoked) - min do
-        0 -> acc
-        ^default -> [{:unused_args, tuple} | acc]
-        unused_args -> [{:unused_args, tuple, unused_args} | acc]
-      end
-    end
-  end
-
-  @doc false
-  def cache_env(pid, env) do
-    :gen_server.call(pid, {:cache_env, env}, @timeout)
-  end
-
-  @doc false
-  def get_cached_env(pid, ref) do
-    :gen_server.call(pid, {:get_cached_env, ref}, @timeout)
-  end
-
-  # Stops the gen server
-  @doc false
-  def stop(pid) do
-    :gen_server.cast(pid, :stop)
-  end
-
-  # Callbacks
-
-  def init([]) do
-    d = :digraph.new([:protected])
-    :digraph.add_vertex(d, :local)
-    {:ok, {d, []}}
-  end
-
-  @doc false
-  def handle_call({:cache_env, env}, _from, {d, cache}) do
-    case cache do
-      [{i, ^env} | _] ->
-        {:reply, i, {d, cache}}
-      t ->
-        i = length(t)
-        {:reply, i, {d, [{i, env} | t]}}
-    end
-  end
-
-  def handle_call({:get_cached_env, ref}, _from, {_, cache} = state) do
-    {^ref, env} = :lists.keyfind(ref, 1, cache)
-    {:reply, env, state}
-  end
-
-  def handle_call({:yank, local}, _from, {d, _} = state) do
-    out_vertices = :digraph.out_neighbours(d, local)
-    :digraph.del_edges(d, :digraph.out_edges(d, local))
-    {:reply, {[], out_vertices}, state}
-  end
-
-  def handle_call(:digraph, _from, {d, _} = state) do
-    {:reply, d, state}
-  end
-
-  @doc false
-  def handle_info(_msg, state) do
-    {:noreply, state}
-  end
-
-  def handle_cast({:add_local, from, to}, {d, _} = state) do
-    handle_add_local(d, from, to)
-    {:noreply, state}
-  end
-
-  def handle_cast({:add_import, function, module, {name, arity}}, {d, _} = state) do
-    handle_import(d, function, module, name, arity)
-    {:noreply, state}
-  end
-
-  def handle_cast({:add_definition, kind, tuple}, {d, _} = state) do
-    handle_add_definition(d, kind, tuple)
-    {:noreply, state}
-  end
-
-  def handle_cast({:add_defaults, kind, {name, arity}, defaults}, {d, _} = state) do
-    for i <- :lists.seq(arity - defaults, arity - 1) do
-      handle_add_definition(d, kind, {name, i})
-      handle_add_local(d, {name, i}, {name, i + 1})
-    end
-    {:noreply, state}
-  end
-
-  def handle_cast({:reattach, _kind, tuple, {in_neigh, out_neigh}}, {d, _} = state) do
-    for from <- in_neigh do
-      :digraph.add_vertex(d, from)
-      replace_edge!(d, from, tuple)
-    end
-
-    for to <- out_neigh do
-      :digraph.add_vertex(d, to)
-      replace_edge!(d, tuple, to)
-    end
-
-    {:noreply, state}
-  end
-
-  def handle_cast(:stop, state) do
-    {:stop, :normal, state}
-  end
-
-  @doc false
-  def terminate(_reason, _state) do
-    :ok
-  end
-
-  @doc false
-  def code_change(_old, state, _extra) do
-    {:ok, state}
-  end
-
-  defp handle_import(d, function, module, name, arity) do
-    :digraph.add_vertex(d, module)
-
-    tuple = {:import, name, arity}
-    :digraph.add_vertex(d, tuple)
-    replace_edge!(d, tuple, module)
-
-    if function != nil do
-      replace_edge!(d, function, tuple)
-    end
-
-    :ok
-  end
-
-  defp handle_add_local(d, from, to) do
-    :digraph.add_vertex(d, to)
-    replace_edge!(d, from, to)
-  end
-
-  defp handle_add_definition(d, public, tuple) when public in [:def, :defmacro] do
-    :digraph.add_vertex(d, tuple)
-    replace_edge!(d, :local, tuple)
-  end
-
-  defp handle_add_definition(d, private, tuple) when private in [:defp, :defmacrop] do
-    :digraph.add_vertex(d, tuple)
-  end
-
-  defp replace_edge!(d, from, to) do
-    _ = unless :lists.member(to, :digraph.out_neighbours(d, from)) do
-      [:"$e" | _] = :digraph.add_edge(d, from, to)
-    end
-    :ok
-  end
-end
@@ -1,267 +1,116 @@
 defmodule Node do
  @moduledoc """
-  Functions related to VM nodes.
-
-  Some of the functions in this module are inlined by the compiler,
-  similar to functions in the `Kernel` module and they are explicitly
-  marked in their docs as "inlined by the compiler". For more information
-  about inlined functions, check out the `Kernel` module.
+  Functions related to Erlang nodes.
  """

-  @type t :: node
-
  @doc """
-  Turns a non-distributed node into a distributed node.
-
-  This functionality starts the `:net_kernel` and other
-  related processes.
+  Returns the current node. It returns the same as the built-in node().
  """
-  @spec start(node, :longnames | :shortnames, non_neg_integer) ::
-             {:ok, pid} | {:error, term}
-  def start(name, type \\ :longnames, tick_time \\ 15000) do
-    :net_kernel.start([name, type, tick_time])
-  end
-
-  @doc """
-  Turns a distributed node into a non-distributed node.
-
-  For other nodes in the network, this is the same as the node going down.
-  Only possible when the node was started with `Node.start/3`, otherwise
-  returns `{:error, :not_allowed}`. Returns `{:error, :not_found}` if the
-  local node is not alive.
-  """
-  @spec stop() :: :ok | {:error, :not_allowed | :not_found}
-  def stop() do
-    :net_kernel.stop()
-  end
-
-  @doc """
-  Returns the current node.
-
-  It returns the same as the built-in `node()`.
-  """
-  @spec self :: t
  def self do
    :erlang.node()
  end

  @doc """
-  Returns `true` if the local node is alive.
-
-  That is, if the node can be part of a distributed system.
+  Returns true if the local node is alive; that is, if the node can be
+  part of a distributed system. Otherwise, it returns false.
  """
-  @spec alive? :: boolean
  def alive? do
    :erlang.is_alive()
  end

  @doc """
  Returns a list of all visible nodes in the system, excluding
-  the local node.
-
-  Same as `list(:visible)`.
+  the local node. Same as list(visible).
  """
-  @spec list :: [t]
  def list do
    :erlang.nodes()
  end

  @doc """
-  Returns a list of nodes according to argument given.
-
-  The result returned when the argument is a list, is the list of nodes
+  Returns a list of nodes according to argument given. The result
+  returned when the argument is a list, is the list of nodes
  satisfying the disjunction(s) of the list elements.
-
-  For more information, see
-  [`:erlang.nodes/1`](http://www.erlang.org/doc/man/erlang.html#nodes-1).
+  
+  See http://www.erlang.org/doc/man/erlang.html#nodes-1 for more info.
  """
-  @typep state :: :visible | :hidden | :connected | :this | :known
-  @spec list(state | [state]) :: [t]
  def list(args) do
    :erlang.nodes(args)
  end

  @doc """
-  Monitors the status of the node.
+  Monitors the status of the node. If flag is true, monitoring is
+  turned on. If flag is false, monitoring is turned off.

-  If `flag` is `true`, monitoring is turned on.
-  If `flag` is `false`, monitoring is turned off.
-
-  For more information, see
-  [`:erlang.monitor_node/2`](http://www.erlang.org/doc/man/erlang.html#monitor_node-2).
+  See http://www.erlang.org/doc/man/erlang.html#monitor_node-2 for more info.
  """
-  @spec monitor(t, boolean) :: true
  def monitor(node, flag) do
    :erlang.monitor_node(node, flag)
  end

  @doc """
-  Behaves as `monitor/2` except that it allows an extra
-  option to be given, namely `:allow_passive_connect`.
+  Behaves as monitor_node/2 except that it allows an extra
+  option to be given, namely :allow_passive_connect.

-  For more information, see
-  [`:erlang.monitor_node/3`](http://www.erlang.org/doc/man/erlang.html#monitor_node-3).
+  See http://www.erlang.org/doc/man/erlang.html#monitor_node-3 for more info.
  """
-  @spec monitor(t, boolean, [:allow_passive_connect]) :: true
  def monitor(node, flag, options) do
    :erlang.monitor_node(node, flag, options)
  end

  @doc """
-  Tries to set up a connection to node.
-
-  Returns `:pang` if it fails, or `:pong` if it is successful.
-
-  ## Examples
-
-      iex> Node.ping(:unknown_node)
-      :pang
-
+  Forces the disconnection of a node. This will appear to the `node` as if
+  the local node has crashed. This BIF is mainly used in the Erlang network
+  authentication protocols. Returns true if disconnection succeeds, otherwise
+  false. If the local node is not alive, the function returns ignored.
+  
+  See http://www.erlang.org/doc/man/erlang.html#disconnect_node-1 for more info.
  """
-  @spec ping(t) :: :pong | :pang
-  def ping(node) do
-    :net_adm.ping(node)
-  end
-
-  @doc """
-  Forces the disconnection of a node.
-
-  This will appear to the `node` as if the local node has crashed.
-  This function is mainly used in the Erlang network authentication
-  protocols. Returns `true` if disconnection succeeds, otherwise `false`.
-  If the local node is not alive, the function returns `:ignored`.
-
-  For more information, see
-  [`:erlang.disconnect_node/1`](http://www.erlang.org/doc/man/erlang.html#disconnect_node-1).
-  """
-  @spec disconnect(t) :: boolean | :ignored
  def disconnect(node) do
    :erlang.disconnect_node(node)
  end

  @doc """
-  Establishes a connection to `node`.
+  Returns the pid of a new process started by the application of `fun`
+  on `node`. If `node` does not exist, a useless pid is returned.

-  Returns `true` if successful, `false` if not, and the atom
-  `:ignored` if the local node is not alive.
-
-  For more information, see
-  [`:net_kernel.connect_node/1`](http://www.erlang.org/doc/man/net_kernel.html#connect_node-1).
+  Check http://www.erlang.org/doc/man/erlang.html#spawn_opt-4 for
+  the list of available options.
  """
-  @spec connect(t) :: boolean | :ignored
-  def connect(node) do
-    :net_kernel.connect_node(node)
-  end
-
-  @doc """
-  Returns the PID of a new process started by the application of `fun`
-  on `node`. If `node` does not exist, a useless PID is returned.
-
-  For the list of available options, see
-  [`:erlang.spawn/2`](http://www.erlang.org/doc/man/erlang.html#spawn-2).
-
-  Inlined by the compiler.
-  """
-  @spec spawn(t, (() -> any)) :: pid
-  def spawn(node, fun) do
-    :erlang.spawn(node, fun)
-  end
-
-  @doc """
-  Returns the PID of a new process started by the application of `fun`
-  on `node`.
-
-  If `node` does not exist, a useless PID is returned.
-
-  For the list of available options, see
-  [`:erlang.spawn_opt/3`](http://www.erlang.org/doc/man/erlang.html#spawn_opt-3).
-
-  Inlined by the compiler.
-  """
-  @spec spawn(t, (() -> any), Process.spawn_opts) :: pid | {pid, reference}
-  def spawn(node, fun, opts) do
+  def spawn(node, fun, opts // []) do
    :erlang.spawn_opt(node, fun, opts)
  end

  @doc """
-  Returns the PID of a new process started by the application of
-  `module.function(args)` on `node`.
+  Returns the pid of a new process started by the application of
+  `module.function(args)` on `node`. If `node` does not exists, a useless
+  pid is returned.

-  If `node` does not exist, a useless PID is returned.
-
-  For the list of available options, see
-  [`:erlang.spawn/4`](http://www.erlang.org/doc/man/erlang.html#spawn-4).
-
-  Inlined by the compiler.
+  Check http://www.erlang.org/doc/man/erlang.html#spawn_opt-4 for
+  the list of available options.
  """
-  @spec spawn(t, module, atom, [any]) :: pid
-  def spawn(node, module, fun, args) do
-    :erlang.spawn(node, module, fun, args)
+  def spawn(node, module, fun, args, opts // []) do
+    :erlang.spawn(node, module, fun, args, opts)
  end

  @doc """
-  Returns the PID of a new process started by the application of
-  `module.function(args)` on `node`.
-
-  If `node` does not exist, a useless PID is returned.
-
-  For the list of available options, see
-  [`:erlang.spawn/5`](http://www.erlang.org/doc/man/erlang.html#spawn_opt-5).
-
-  Inlined by the compiler.
+  Returns the pid of a new process started by the application of `fun`
+  on `node`. A link is created between the calling process and the
+  new process, atomically. If `node` does not exist, a useless pid is returned
+  (and due to the link, an exit signal with exit reason :noconnection will be
+  received).
  """
-  @spec spawn(t, module, atom, [any], Process.spawn_opts) :: pid | {pid, reference}
-  def spawn(node, module, fun, args, opts) do
-    :erlang.spawn_opt(node, module, fun, args, opts)
-  end
-
-  @doc """
-  Returns the PID of a new linked process started by the application of `fun` on `node`.
-
-  A link is created between the calling process and the new process, atomically.
-  If `node` does not exist, a useless PID is returned (and due to the link, an exit
-  signal with exit reason `:noconnection` will be received).
-
-  Inlined by the compiler.
-  """
-  @spec spawn_link(t, (() -> any)) :: pid
  def spawn_link(node, fun) do
    :erlang.spawn_link(node, fun)
  end

  @doc """
-  Returns the PID of a new linked process started by the application of
-  `module.function(args)` on `node`.
-
-  A link is created between the calling process and the new process, atomically.
-  If `node` does not exist, a useless PID is returned (and due to the link, an exit
-  signal with exit reason `:noconnection` will be received).
-
-  Inlined by the compiler.
+  Returns the pid of a new process started by the application of
+  `module.function(args)` on `node`. A link is created between the calling
+  process and the new process, atomically. If `node` does not exist, a useless
+  pid is returned (and due to the link, an exit signal with exit reason
+  :noconnection will be received).
  """
-  @spec spawn_link(t, module, atom, [any]) :: pid
  def spawn_link(node, module, fun, args) do
    :erlang.spawn_link(node, module, fun, args)
  end
-
-  @doc """
-  Sets the magic cookie of `node` to the atom `cookie`.
-
-  The default node is `Node.self/0`, the local node. If `node` is the local node,
-  the function also sets the cookie of all other unknown nodes to `cookie`.
-
-  This function will raise `FunctionClauseError` if the given `node` is not alive.
-  """
-  def set_cookie(node \\ Node.self, cookie) when is_atom(cookie) do
-    :erlang.set_cookie(node, cookie)
-  end
-
-  @doc """
-  Returns the magic cookie of the local node.
-
-  Returns the cookie if the node is alive, otherwise `:nocookie`.
-  """
-  def get_cookie() do
-    :erlang.get_cookie()
-  end
-end
+end
@@ -1,758 +1,140 @@
 defmodule OptionParser do
-  @moduledoc """
-  This module contains functions to parse command line options.
-  """
-
-  @type argv    :: [String.t]
-  @type parsed  :: Keyword.t
-  @type errors  :: [{String.t, String.t | nil}]
-  @type options :: [switches: Keyword.t, strict: Keyword.t, aliases: Keyword.t]
-
-  defmodule ParseError do
-    defexception [:message]
-  end
-
  @doc """
-  Parses `argv` into a keyword list.
+  Parses the argv and returns one tuple with parsed options
+  and the arguments.

-  It returns a three-element tuple with the form `{parsed, args, invalid}`, where:
+  ## Examples

-    * `parsed` is a keyword list of parsed switches with `{switch_name, value}`
-      tuples in it; `switch_name` is the atom representing the switch name while
-      `value` is the value for that switch parsed according to `opts` (see the
-      "Examples" section for more information)
-    * `args` is a list of the remaining arguments in `argv` as strings
-    * `invalid` is a list of invalid options as `{option_name, value}` where
-      `option_name` is the raw option and `value` is `nil` if the option wasn't
-      expected or the string value if the value didn't have the expected type for
-      the corresponding option
+      OptionParser.parse(["--debug"])
+      #=> { [debug: true], [] }

-  Elixir converts switches to underscored atoms, so `--source-path` becomes
-  `:source_path`. This is done to better suit Elixir conventions. However, this
-  means that switches can't contain underscores and switches that do contain
-  underscores are always returned in the list of invalid switches.
+      OptionParser.parse(["--source", "lib"])
+      #=> { [source: "lib"], [] }

-  When parsing, it is common to list switches and their expected types:
-
-      iex> OptionParser.parse(["--debug"], switches: [debug: :boolean])
-      {[debug: true], [], []}
-
-      iex> OptionParser.parse(["--source", "lib"], switches: [source: :string])
-      {[source: "lib"], [], []}
-
-      iex> OptionParser.parse(["--source-path", "lib", "test/enum_test.exs", "--verbose"],
-      ...>                    switches: [source_path: :string, verbose: :boolean])
-      {[source_path: "lib", verbose: true], ["test/enum_test.exs"], []}
-
-  We will explore the valid switches and operation modes of option parser below.
-
-  ## Options
-
-  The following options are supported:
-
-    * `:switches` or `:strict` - see the "Switch definitions" section below
-    * `:allow_nonexistent_atoms` - see the "Parsing dynamic switches" section below
-    * `:aliases` - see the "Aliases" section below
-
-  ## Switch definitions
-
-  Switches can be specified via one of two options:
-
-    * `:switches` - defines some switches and their types. This function
-      still attempts to parse switches that are not in this list.
-    * `:strict` - defines strict switches. Any switch in `argv` that is not
-      specified in the list is returned in the invalid options list.
-
-  Both these options accept a keyword list of `{name, type}` tuples where `name`
-  is an atom defining the name of the switch and `type` is an atom that
-  specifies the type for the value of this switch (see the "Types" section below
-  for the possible types and more information about type casting).
-
-  Note that you should only supply the `:switches` or the`:strict` option.
-  If you supply both, an `ArgumentError` exception will be raised.
-
-  ### Types
-
-  Switches parsed by `OptionParser` may take zero or one arguments.
-
-  The following switches types take no arguments:
-
-    * `:boolean` - sets the value to `true` when given (see also the
-      "Negation switches" section below)
-    * `:count` - counts the number of times the switch is given
-
-  The following switches take one argument:
-
-    * `:integer` - parses the value as an integer
-    * `:float` - parses the value as a float
-    * `:string` - parses the value as a string
-
-  If a switch can't be parsed according to the given type, it is
-  returned in the invalid options list.
-
-  ### Modifiers
-
-  Switches can be specified with modifiers, which change how
-  they behave. The following modifiers are supported:
-
-    * `:keep` - keeps duplicated items instead of overriding them;
-      works with all types except `:count`. Specifying `switch_name: :keep`
-      assumes the type of `:switch_name` will be `:string`.
-
-  To use `:keep` with a type other than `:string`, use a list as the type
-  for the switch. For example: `[foo: [:integer, :keep]]`.
-
-  ### Negation switches
-
-  In case a switch `SWITCH` is specified to have type `:boolean`, it may be
-  passed as `--no-SWITCH` as well which will set the option to `false`:
-
-      iex> OptionParser.parse(["--no-op", "path/to/file"], switches: [op: :boolean])
-      {[op: false], ["path/to/file"], []}
-
-  ### Parsing dynamic switches
-
-  `OptionParser` also includes a dynamic mode where it will attempt to parse
-  switches dynamically. Such can be done by not specifying the `:switches` or
-  `:strict` option.
-
-      iex> OptionParser.parse(["--debug"])
-      {[debug: true], [], []}
-
-
-  Switches followed by a value will be assigned the value, as a string. Switches
-  without an argument, like `--debug` in the examples above, will automatically be
-  set to `true`.
-
-  Since Elixir converts switches to atoms, the dynamic mode will only parse
-  switches that translates to atoms used by the runtime. Therefore, the code below
-  likely won't parse the given option since the `:option_parser_example` atom is
-  never used anywhere:
-
-      OptionParser.parse(["--option-parser-example"])
-      # Does nothing more...
-
-  However, the code below does since the `:option_parser_example` atom is used
-  at some point later (or earlier) on:
-
-      {opts, _, _} = OptionParser.parse(["--option-parser-example"])
-      opts[:option_parser_example]
-
-  In other words, when using dynamic mode, Elixir will do the correct thing and
-  only parse options that are used by the runtime, ignoring all others. If you
-  would like to parse all switches, regardless if they exist or not, you can
-  force creation of atoms by passing `allow_nonexistent_atoms: true` as option.
-  Such option is useful when you are building command-line applications that
-  receive dynamically-named arguments but must be used with care on long-running
-  systems.
-
-  Switches followed by a value will be assigned the value, as a string.
-  Switches without an argument, like `--debug` in the examples above, will
-  automatically be set to `true`.
+      OptionParser.parse(["--source", "lib", "test/enum_test.exs", "--verbose"])
+      #=> { [source: "lib", verbose: true], ["test/enum_test.exs"] }

  ## Aliases

-  A set of aliases can be specified in the `:aliases` option:
+  A set of aliases can be given as second argument:

-      iex> OptionParser.parse(["-d"], aliases: [d: :debug])
-      {[debug: true], [], []}
+      OptionParser.parse(["-d"], aliases: [d: :debug])
+      #=> { [debug: true], [] }

-  ## Examples
+  ## Flags

-  Here are some examples of working with different types and modifiers:
+  A set of flags can be given as argument too. Those are considered
+  boolean and never consume the next value unless it is a boolean:

-      iex> OptionParser.parse(["--unlock", "path/to/file"], strict: [unlock: :boolean])
-      {[unlock: true], ["path/to/file"], []}
+      OptionParser.parse(["--unlock path/to/file"], flags: [:unlock])
+      #=> { [unlock: true], ["path/to/file"] }

-      iex> OptionParser.parse(["--unlock", "--limit", "0", "path/to/file"],
-      ...>                    strict: [unlock: :boolean, limit: :integer])
-      {[unlock: true, limit: 0], ["path/to/file"], []}
+      OptionParser.parse(["--unlock false path/to/file"], flags: [:unlock])
+      #=> { [unlock: false], ["path/to/file"] }

-      iex> OptionParser.parse(["--limit", "3"], strict: [limit: :integer])
-      {[limit: 3], [], []}
+  ## Negation switches

-      iex> OptionParser.parse(["--limit", "xyz"], strict: [limit: :integer])
-      {[], [], [{"--limit", "xyz"}]}
+  Any switches starting with `--no-` are always considered to be
+  booleans and never parse the next value.

-      iex> OptionParser.parse(["--verbose"], switches: [verbose: :count])
-      {[verbose: 1], [], []}
-
-      iex> OptionParser.parse(["-v", "-v"], aliases: [v: :verbose], strict: [verbose: :count])
-      {[verbose: 2], [], []}
-
-      iex> OptionParser.parse(["--unknown", "xyz"], strict: [])
-      {[], ["xyz"], [{"--unknown", nil}]}
-
-      iex> OptionParser.parse(["--limit", "3", "--unknown", "xyz"],
-      ...>                    switches: [limit: :integer])
-      {[limit: 3, unknown: "xyz"], [], []}
-
-      iex> OptionParser.parse(["--unlock", "path/to/file", "--unlock", "path/to/another/file"], strict: [unlock: :keep])
-      {[unlock: "path/to/file", unlock: "path/to/another/file"], [], []}
+      OptionParser.parse(["--no-op path/to/file"])
+      #=> { [no_op: true], ["path/to/file"] }

  """
-  @spec parse(argv, options) :: {parsed, argv, errors}
-  def parse(argv, opts \\ []) when is_list(argv) and is_list(opts) do
-    do_parse(argv, compile_config(opts), [], [], [], true)
+  def parse(argv, opts // []) when is_list(argv) and is_list(opts) do
+    aliases = opts[:aliases] || []
+    flags   = opts[:flags]   || []
+    dict    = Keyword.new(flags, fn(k) -> { k, false } end)
+    parse(argv, aliases, flags, dict, [], true)
  end

  @doc """
-  The same as `parse/2` but raises an `OptionParser.ParseError`
-  exception if any invalid options are given.
+  Similar to parse but only parses the head of the argv.
+  I.e. as soon as it finds a non switch, it stops parsing.

-  If there are no errors, returns a `{parsed, rest}` tuple where:
-
-    * `parsed` is the list of parsed switches (same as in `parse/2`)
-    * `rest` is the list of arguments (same as in `parse/2`)
-
-  ## Examples
-
-      iex> OptionParser.parse!(["--debug", "path/to/file"], strict: [debug: :boolean])
-      {[debug: true], ["path/to/file"]}
-
-      iex> OptionParser.parse!(["--limit", "xyz"], strict: [limit: :integer])
-      ** (OptionParser.ParseError) 1 error found!
-      --limit : Expected type integer, got "xyz"
-
-      iex> OptionParser.parse!(["--unknown", "xyz"], strict: [])
-      ** (OptionParser.ParseError) 1 error found!
-      --unknown : Unknown option
-
-      iex> OptionParser.parse!(["-l", "xyz", "-f", "bar"],
-      ...>                     switches: [limit: :integer, foo: :integer], aliases: [l: :limit, f: :foo])
-      ** (OptionParser.ParseError) 2 errors found!
-      -l : Expected type integer, got "xyz"
-      -f : Expected type integer, got "bar"
-
-  """
-  @spec parse!(argv, options) :: {parsed, argv} | no_return
-  def parse!(argv, opts \\ []) when is_list(argv) and is_list(opts) do
-    case parse(argv, opts) do
-      {parsed, args, []} -> {parsed, args}
-      {_, _, errors} -> raise ParseError, format_errors(errors, opts)
-    end
-  end
-
-  @doc """
-  Similar to `parse/2` but only parses the head of `argv`;
-  as soon as it finds a non-switch, it stops parsing.
-
-  See `parse/2` for more information.
+  Check `parse/2` for more info.

  ## Example

-      iex> OptionParser.parse_head(["--source", "lib", "test/enum_test.exs", "--verbose"],
-      ...>                         switches: [source: :string, verbose: :boolean])
-      {[source: "lib"], ["test/enum_test.exs", "--verbose"], []}
-
-      iex> OptionParser.parse_head(["--verbose", "--source", "lib", "test/enum_test.exs", "--unlock"],
-      ...>                         switches: [source: :string, verbose: :boolean, unlock: :boolean])
-      {[verbose: true, source: "lib"], ["test/enum_test.exs", "--unlock"], []}
+      OptionParser.parse_head(["--source", "lib", "test/enum_test.exs", "--verbose"])
+      #=> { [source: "lib"], ["test/enum_test.exs", "--verbose"] }

  """
-  @spec parse_head(argv, options) :: {parsed, argv, errors}
-  def parse_head(argv, opts \\ []) when is_list(argv) and is_list(opts) do
-    do_parse(argv, compile_config(opts), [], [], [], false)
-  end
-
-  @doc """
-  The same as `parse_head/2` but raises an `OptionParser.ParseError`
-  exception if any invalid options are given.
-
-  If there are no errors, returns a `{parsed, rest}` tuple where:
-
-    * `parsed` is the list of parsed switches (same as in `parse_head/2`)
-    * `rest` is the list of arguments (same as in `parse_head/2`)
-
-  ## Examples
-
-      iex> OptionParser.parse_head!(["--source", "lib", "path/to/file", "--verbose"],
-      ...>                         switches: [source: :string, verbose: :boolean])
-      {[source: "lib"], ["path/to/file", "--verbose"]}
-
-      iex> OptionParser.parse_head!(["--number", "lib", "test/enum_test.exs", "--verbose"],
-      ...>                          strict: [number: :integer])
-      ** (OptionParser.ParseError) 1 error found!
-      --number : Expected type integer, got "lib"
-
-      iex> OptionParser.parse_head!(["--verbose", "--source", "lib", "test/enum_test.exs", "--unlock"],
-      ...>                          strict: [verbose: :integer, source: :integer])
-      ** (OptionParser.ParseError) 2 errors found!
-      --verbose : Missing argument of type integer
-      --source : Expected type integer, got "lib"
-  """
-  @spec parse_head!(argv, options) :: {parsed, argv} | no_return
-  def parse_head!(argv, opts \\ []) when is_list(argv) and is_list(opts) do
-    case parse_head(argv, opts) do
-      {parsed, args, []} -> {parsed, args}
-      {_, _, errors} -> raise ParseError, format_errors(errors, opts)
-    end
-  end
-
-  defp do_parse([], _config, opts, args, invalid, _all?) do
-    {Enum.reverse(opts), Enum.reverse(args), Enum.reverse(invalid)}
-  end
-
-  defp do_parse(argv, {aliases, switches, strict?, allow_nonexistent_atoms?} = config, opts, args, invalid, all?) do
-    case next(argv, aliases, switches, strict?, allow_nonexistent_atoms?) do
-      {:ok, option, value, rest} ->
-        # the option exists and it was successfully parsed
-        kinds = List.wrap Keyword.get(switches, option)
-        new_opts = store_option(opts, option, value, kinds)
-        do_parse(rest, config, new_opts, args, invalid, all?)
-
-      {:invalid, option, value, rest} ->
-        # the option exist but it has wrong value
-        do_parse(rest, config, opts, args, [{option, value} | invalid], all?)
-
-      {:undefined, option, _value, rest} ->
-        # the option does not exist (for strict cases)
-        do_parse(rest, config, opts, args, [{option, nil} | invalid], all?)
-
-      {:error, ["--" | rest]} ->
-        {Enum.reverse(opts), Enum.reverse(args, rest), Enum.reverse(invalid)}
-
-      {:error, [arg | rest] = remaining_args} ->
-        # there is no option
-        if all? do
-          do_parse(rest, config, opts, [arg | args], invalid, all?)
-        else
-          {Enum.reverse(opts), Enum.reverse(args, remaining_args), Enum.reverse(invalid)}
-        end
-    end
-  end
-
-  @doc """
-  Low-level function that parses one option.
-
-  It accepts the same options as `parse/2` and `parse_head/2`
-  as both functions are built on top of this function. This function
-  may return:
-
-    * `{:ok, key, value, rest}` - the option `key` with `value` was
-      successfully parsed
-
-    * `{:invalid, key, value, rest}` - the option `key` is invalid with `value`
-      (returned when the value cannot be parsed according to the switch type)
-
-    * `{:undefined, key, value, rest}` - the option `key` is undefined
-      (returned in strict mode when the switch is unknown)
-
-    * `{:error, rest}` - there are no switches at the head of the given `argv`
-
-  """
-  @spec next(argv, options) ::
-        {:ok, key :: atom, value :: term, argv} |
-        {:invalid, String.t, String.t | nil, argv} |
-        {:undefined, String.t, String.t | nil, argv} |
-        {:error, argv}
-
-  def next(argv, opts \\ []) when is_list(argv) and is_list(opts) do
-    {aliases, switches, strict?, allow_nonexistent_atoms?} = compile_config(opts)
-    next(argv, aliases, switches, strict?, allow_nonexistent_atoms?)
-  end
-
-  defp next([], _aliases, _switches, _strict?, _allow_nonexistent_atoms?) do
-    {:error, []}
-  end
-
-  defp next(["--" | _] = argv, _aliases, _switches, _strict?, _allow_nonexistent_atoms?) do
-    {:error, argv}
-  end
-
-  defp next(["-" | _] = argv, _aliases, _switches, _strict?, _allow_nonexistent_atoms?) do
-    {:error, argv}
-  end
-
-  defp next(["- " <> _ | _] = argv, _aliases, _switches, _strict?, _allow_nonexistent_atoms?) do
-    {:error, argv}
-  end
-
-  # Handles --foo or --foo=bar
-  defp next(["--" <> option | rest], _aliases, switches, strict?, allow_nonexistent_atoms?) do
-    {option, value} = split_option(option)
-    tagged = tag_option(option, switches, allow_nonexistent_atoms?)
-    do_next(tagged, value, "--" <> option, rest, switches, strict?, allow_nonexistent_atoms?)
-  end
-
-  # Handles -a, -abc, -abc=something
-  defp next(["-" <> option | rest] = argv, aliases, switches, strict?, allow_nonexistent_atoms?) do
-    {option, value} = split_option(option)
-    original = "-" <> option
-
-    cond do
-      is_nil(value) and negative_number?(original) ->
-        {:error, argv}
-      String.contains?(option, ["-", "_"]) ->
-        {:undefined, original, value, rest}
-      String.length(option) > 1 ->
-        key = get_option_key(option, allow_nonexistent_atoms?)
-        option_key = aliases[key]
-        if key && option_key do
-          IO.warn "multi-letter aliases are deprecated, got: #{inspect(key)}"
-          do_next({:default, option_key}, value, original, rest, switches, strict?, allow_nonexistent_atoms?)
-        else
-          next(expand_multiletter_alias(option, value) ++ rest, aliases, switches, strict?, allow_nonexistent_atoms?)
-        end
-      true ->
-        # We have a regular one-letter alias here
-        tagged = tag_oneletter_alias(option, aliases, allow_nonexistent_atoms?)
-        do_next(tagged, value, original, rest, switches, strict?, allow_nonexistent_atoms?)
-    end
-  end
-
-  defp next(argv, _aliases, _switches, _strict?, _allow_nonexistent_atoms?) do
-    {:error, argv}
-  end
-
-  defp do_next(tagged, value, original, rest, switches, strict?, allow_nonexistent_atoms?) do
-    if strict? and not option_defined?(tagged, switches) do
-      {:undefined, original, value, rest}
-    else
-      {option, kinds, value} = normalize_option(tagged, value, switches)
-      {value, kinds, rest} = normalize_value(value, kinds, rest, strict?)
-      case validate_option(value, kinds) do
-        {:ok, new_value} -> {:ok, option, new_value, rest}
-        :invalid         -> {:invalid, original, value, rest}
-      end
-    end
-  end
-
-  @doc """
-  Receives a key-value enumerable and converts it to `t:argv/0`.
-
-  Keys must be atoms. Keys with `nil` value are discarded,
-  boolean values are converted to `--key` or `--no-key`
-  (if the value is `true` or `false`, respectively),
-  and all other values are converted using `Kernel.to_string/1`.
-
-  It is advised to pass to `to_argv/2` the same set of `options`
-  given to `parse/2`. Some switches can only be reconstructed
-  correctly with the `switches` information in hand.
-
-  ## Examples
-
-      iex>  OptionParser.to_argv([foo_bar: "baz"])
-      ["--foo-bar", "baz"]
-      iex>  OptionParser.to_argv([bool: true, bool: false, discarded: nil])
-      ["--bool", "--no-bool"]
-
-  Some switches will output different values based on the switches
-  flag:
-
-      iex> OptionParser.to_argv([number: 2], switches: [])
-      ["--number", "2"]
-      iex> OptionParser.to_argv([number: 2], switches: [number: :count])
-      ["--number", "--number"]
-
-  """
-  @spec to_argv(Enumerable.t, options) :: argv
-  def to_argv(enum, opts \\ []) do
-    switches = Keyword.get(opts, :switches, [])
-    Enum.flat_map(enum, fn
-      {_key, nil}  -> []
-      {key, true}  -> [to_switch(key)]
-      {key, false} -> [to_switch(key, "--no-")]
-      {key, value} -> to_argv(key, value, switches)
-    end)
-  end
-
-  defp to_argv(key, value, switches) do
-    if switches[key] == :count do
-      List.duplicate(to_switch(key), value)
-    else
-      [to_switch(key), to_string(value)]
-    end
-  end
-
-  defp to_switch(key, prefix \\ "--") when is_atom(key) do
-    prefix <> String.replace(Atom.to_string(key), "_", "-")
-  end
-
-  @doc ~S"""
-  Splits a string into `t:argv/0` chunks.
-
-  This function splits the given `string` into a list of strings in a similar
-  way to many shells.
-
-  ## Examples
-
-      iex> OptionParser.split("foo bar")
-      ["foo", "bar"]
-
-      iex> OptionParser.split("foo \"bar baz\"")
-      ["foo", "bar baz"]
-
-  """
-  @spec split(String.t) :: argv
-  def split(string) do
-    do_split(String.trim_leading(string, " "), "", [], nil)
-  end
-
-  # If we have an escaped quote, simply remove the escape
-  defp do_split(<<?\\, quote, t::binary>>, buffer, acc, quote),
-    do: do_split(t, <<buffer::binary, quote>>, acc, quote)
-
-  # If we have a quote and we were not in a quote, start one
-  defp do_split(<<quote, t::binary>>, buffer, acc, nil) when quote in [?", ?'],
-    do: do_split(t, buffer, acc, quote)
-
-  # If we have a quote and we were inside it, close it
-  defp do_split(<<quote, t::binary>>, buffer, acc, quote),
-    do: do_split(t, buffer, acc, nil)
-
-  # If we have an escaped quote/space, simply remove the escape as long as we are not inside a quote
-  defp do_split(<<?\\, h, t::binary>>, buffer, acc, nil) when h in [?\s, ?', ?"],
-    do: do_split(t, <<buffer::binary, h>>, acc, nil)
-
-  # If we have space and we are outside of a quote, start new segment
-  defp do_split(<<?\s, t::binary>>, buffer, acc, nil),
-    do: do_split(String.trim_leading(t, " "), "", [buffer | acc], nil)
-
-  # All other characters are moved to buffer
-  defp do_split(<<h, t::binary>>, buffer, acc, quote) do
-    do_split(t, <<buffer::binary, h>>, acc, quote)
-  end
-
-  # Finish the string expecting a nil marker
-  defp do_split(<<>>, "", acc, nil),
-    do: Enum.reverse(acc)
-
-  defp do_split(<<>>, buffer, acc, nil),
-    do: Enum.reverse([buffer | acc])
-
-  # Otherwise raise
-  defp do_split(<<>>, _, _acc, marker) do
-    raise "argv string did not terminate properly, a #{<<marker>>} was opened but never closed"
+  def parse_head(argv, opts // []) when is_list(argv) and is_list(opts) do
+    aliases = opts[:aliases] || []
+    flags   = opts[:flags]   || []
+    dict    = Keyword.new(flags, fn(k) -> { k, false } end)
+    parse(argv, aliases, flags, dict, [], false)
  end

  ## Helpers

-  defp compile_config(opts) do
-    aliases = opts[:aliases] || []
-    allow_nonexistent_atoms? = opts[:allow_nonexistent_atoms] || false
+  defp parse(["-" <> option|t], aliases, flags, dict, args, all) do
+    { option, value } = normalize_option(option, aliases)

-    {switches, strict?} = cond do
-      opts[:switches] && opts[:strict] ->
-        raise ArgumentError, ":switches and :strict cannot be given together"
-      switches = opts[:switches] ->
-        {switches, false}
-      strict = opts[:strict] ->
-        {strict, true}
-      true ->
-        {[], false}
-    end
-
-    {aliases, switches, strict?, allow_nonexistent_atoms?}
-  end
-
-  defp validate_option(value, kinds) do
-    {invalid?, value} =
-      cond do
-        :invalid in kinds ->
-          {true, value}
-        :boolean in kinds ->
-          case value do
-            t when t in [true, "true"] -> {false, true}
-            f when f in [false, "false"] -> {false, false}
-            _ -> {true, value}
-          end
-        :count in kinds ->
-          case value do
-            1 -> {false, value}
-            _ -> {true, value}
-          end
-        :integer in kinds ->
-          case Integer.parse(value) do
-            {value, ""} -> {false, value}
-            _ -> {true, value}
-          end
-        :float in kinds ->
-          case Float.parse(value) do
-            {value, ""} -> {false, value}
-            _ -> {true, value}
-          end
-        true ->
-          {false, value}
+    if value == nil do
+      { value, t } = if is_flag?(flags, option) do
+        flag_from_tail(t)
+      else
+        value_from_tail(t)
      end
-
-    if invalid? do
-      :invalid
-    else
-      {:ok, value}
    end
+
+    dict = store_option dict, option, value
+    parse(t, aliases, flags, dict, args, all)
  end

-  defp store_option(dict, option, value, kinds) do
-    cond do
-      :count in kinds ->
-        Keyword.update(dict, option, value, & &1 + 1)
-      :keep in kinds ->
-        [{option, value} | dict]
-      true ->
-        [{option, value} | Keyword.delete(dict, option)]
-    end
+  defp parse([], _, _, dict, args, true) do
+    { dict, List.reverse(args) }
  end

-  defp tag_option("no-" <> option = original, switches, allow_nonexistent_atoms?) do
-    cond do
-      (negated = get_option_key(option, allow_nonexistent_atoms?)) && :boolean in List.wrap(switches[negated]) ->
-        {:negated, negated}
-      option_key = get_option_key(original, allow_nonexistent_atoms?) ->
-        {:default, option_key}
-      true ->
-        :unknown
-    end
+  defp parse([h|t], aliases, flags, dict, args, true) do
+    parse(t, aliases, flags, dict, [h|args], true)
  end

-  defp tag_option(option, _switches, allow_nonexistent_atoms?) do
-    if option_key = get_option_key(option, allow_nonexistent_atoms?) do
-      {:default, option_key}
-    else
-      :unknown
-    end
+  defp parse(value, _, _, dict, _args, false) do
+    { dict, value }
  end

-  defp tag_oneletter_alias(alias, aliases, allow_nonexistent_atoms?) when is_binary(alias) do
-    if option_key = aliases[to_existing_key(alias, allow_nonexistent_atoms?)] do
-      {:default, option_key}
-    else
-      :unknown
-    end
+  defp flag_from_tail([h|t]) when h in ["false", "true"], do: { h, t }
+  defp flag_from_tail(t)                                , do: { true, t }
+
+  defp value_from_tail(["-" <> _|_] = t), do: { true, t }
+  defp value_from_tail([h|t]),            do: { h, t }
+  defp value_from_tail([]),               do: { true, [] }
+
+  defp store_option(dict, option, value) when value in ["false", "true"] do
+    store_option(dict, option, binary_to_atom(value))
  end

-  defp expand_multiletter_alias(letters, value) when is_binary(letters) do
-    {last, expanded} =
-      letters
-      |> String.codepoints()
-      |> Enum.map(&("-" <> &1))
-      |> List.pop_at(-1)
-    expanded ++ [last <> if(value, do: "=" <> value, else: "")]
+  defp store_option(dict, option, value) do
+    Keyword.put dict, option, value
  end

-  defp option_defined?(:unknown, _switches) do
-    false
+  defp normalize_option(<<?-, option|:binary>>, aliases) do
+    normalize_option(option, aliases)
  end

-  defp option_defined?({:negated, option}, switches) do
-    Keyword.has_key?(switches, option)
+  defp normalize_option(option, aliases) do
+    { option, value } = split_option(option)
+    if is_no?(option), do: value = true
+    atom = option /> to_underscore /> binary_to_atom
+    { aliases[atom] || atom, value }
  end

-  defp option_defined?({:default, option}, switches) do
-    Keyword.has_key?(switches, option)
-  end
-
-  defp normalize_option(:unknown, value, _switches) do
-    {nil, [:invalid], value}
-  end
-
-  defp normalize_option({:negated, option}, value, switches) do
-    if value do
-      {option, [:invalid], value}
-    else
-      {option, List.wrap(switches[option]), false}
-    end
-  end
-
-  defp normalize_option({:default, option}, value, switches) do
-    {option, List.wrap(switches[option]), value}
-  end
-
-  defp normalize_value(nil, kinds, t, strict?) do
-    cond do
-      :boolean in kinds ->
-        {true, kinds, t}
-      :count in kinds ->
-        {1, kinds, t}
-      value_in_tail?(t) ->
-        [h | t] = t
-        {h, kinds, t}
-      kinds == [] and strict? ->
-        {nil, kinds, t}
-      kinds == [] ->
-        {true, kinds, t}
-      true ->
-        {nil, [:invalid], t}
-    end
-  end
-
-  defp normalize_value(value, kinds, t, _strict?) do
-    {value, kinds, t}
-  end
-
-  defp value_in_tail?(["-" | _]),        do: true
-  defp value_in_tail?(["- " <> _ | _]),  do: true
-  defp value_in_tail?(["-" <> arg | _]), do: negative_number?("-" <> arg)
-  defp value_in_tail?([]),               do: false
-  defp value_in_tail?(_),                do: true
-
  defp split_option(option) do
    case :binary.split(option, "=") do
-      [h]    -> {h, nil}
-      [h, t] -> {h, t}
+      [h]   -> { h, nil }
+      [h|t] -> { h, Enum.join(t, "=") }
    end
  end

-  defp to_underscore(option),
-    do: to_underscore(option, <<>>)
-  defp to_underscore("_" <> _rest, _acc),
-    do: nil
-  defp to_underscore("-" <> rest, acc),
-    do: to_underscore(rest, acc <> "_")
-  defp to_underscore(<<c>> <> rest, acc),
-    do: to_underscore(rest, <<acc::binary, c>>)
-  defp to_underscore(<<>>, acc),
-    do: acc
-
-  def get_option_key(option, allow_nonexistent_atoms?) do
-    if string = to_underscore(option) do
-      to_existing_key(string, allow_nonexistent_atoms?)
-    end
+  defp to_underscore(option) do
+    bc <<c>> inbits option, do: << if c == ?-, do: ?_, else: c >>
  end

-  defp to_existing_key(option, true),
-    do: String.to_atom(option)
-  defp to_existing_key(option, false) do
-    try do
-      String.to_existing_atom(option)
-    rescue
-      ArgumentError -> nil
-    end
-  end
+  defp is_no?("no-" <> _), do: true
+  defp is_no?(_),          do: false

-  defp negative_number?(arg) do
-    match?({_, ""}, Float.parse(arg))
-  end
-
-  defp format_errors([_ | _] = errors, opts) do
-    types = opts[:switches] || opts[:strict]
-    error_count = length(errors)
-    error = if error_count == 1, do: "error", else: "errors"
-    "#{error_count} #{error} found!\n" <>
-      Enum.map_join(errors, "\n", &format_error(&1, opts, types))
-  end
-
-  defp format_error({option, nil}, opts, types) do
-    if type = get_type(option, opts, types) do
-      "#{option} : Missing argument of type #{type}"
-    else
-      "#{option} : Unknown option"
-    end
-  end
-
-  defp format_error({option, value}, opts, types) do
-    type = get_type(option, opts, types)
-    "#{option} : Expected type #{type}, got #{inspect value}"
-  end
-
-  defp get_type(option, opts, types) do
-    allow_nonexistent_atoms? = opts[:allow_nonexistent_atoms] || false
-    key = option |> String.trim_leading("-") |> get_option_key(allow_nonexistent_atoms?)
-
-    if option_key = opts[:aliases][key] do
-      types[option_key]
-    else
-      types[key]
-    end
-  end
-end
+  defp is_flag?(flags, option), do: List.member?(flags, option)
+end
@@ -0,0 +1,84 @@
+defimpl Dict, for: Orddict do
+  defmacrop dict(data) do
+    quote do
+      { Orddict, unquote(data) }
+    end
+  end
+
+  def keys(dict(data)) do
+    lc { k, _ } inlist data, do: k
+  end
+
+  def values(dict(data)) do
+    lc { _, v } inlist data, do: v
+  end
+
+  def size(dict(data)) do
+    length(data)
+  end
+
+  def has_key?(dict(data), key) do
+    :orddict.is_key key, data
+  end
+
+  def get(dict(data), key, default // nil) do
+    case :orddict.find(key, data) do
+      {:ok, value} ->
+        value
+      :error ->
+        default
+    end
+  end
+
+  def put(dict(data), key, value) do
+    dict(:orddict.store key, value, data)
+  end
+
+  def delete(dict(data), key) do
+    dict(:orddict.erase key, data)
+  end
+
+  def merge(dict(d1), dict(d2)) do
+    dict(:orddict.merge fn _k, _v1, v2 -> v2 end, d1, d2)
+  end
+
+  def merge(dict(d1), dict(d2), fun) do
+    dict(:orddict.merge fun, d1, d2)
+  end
+
+  def update(dict(data), key, fun) do
+    dict(:orddict.update key, fun, data)
+  end
+
+  def update(dict(data), key, initial, fun) do
+    dict(:orddict.update key, fun, initial, data)
+  end
+
+  def empty(_) do
+    dict([])
+  end
+
+  def to_list(dict(data)) do
+    data
+  end
+end
+
+defimpl Enum.Iterator, for: Orddict do
+  def iterator({ Orddict, data }), do: data
+  def count({ Orddict, data }),    do: length(data)
+end
+
+defimpl Enum.OrdIterator, for: Orddict do
+  def iterator({ Orddict, data }), do: data
+  def to_list({ h, next }, _), do: [h|next]
+end
+
+defmodule Orddict do
+  @moduledoc """
+  This module implements a dictionary based that stores items
+  as a list of tuples. It is a simple wrapper around
+  [Erlang's orddict module](http://www.erlang.org/doc/man/orddict.html)
+  and exposed via the `Dict` protocol.
+  """
+  use Dict.Common, Dict.Orddict
+end
@@ -1,658 +0,0 @@
-defmodule Path do
-  @moduledoc """
-  This module provides conveniences for manipulating or
-  retrieving file system paths.
-
-  The functions in this module may receive a chardata as
-  argument (i.e. a string or a list of characters / string)
-  and will always return a string (encoded in UTF-8).
-
-  The majority of the functions in this module do not
-  interact with the file system, except for a few functions
-  that require it (like `wildcard/2` and `expand/1`).
-  """
-
-  alias :filename, as: FN
-  @type t :: :unicode.chardata()
-
-  @doc """
-  Converts the given path to an absolute one. Unlike
-  `expand/1`, no attempt is made to resolve `..`, `.` or `~`.
-
-  ## Unix examples
-
-      Path.absname("foo")
-      #=> "/usr/local/foo"
-
-      Path.absname("../x")
-      #=> "/usr/local/../x"
-
-  ## Windows
-
-      Path.absname("foo").
-      "D:/usr/local/foo"
-      Path.absname("../x").
-      "D:/usr/local/../x"
-
-  """
-  @spec absname(t) :: binary
-  def absname(path) do
-    absname(path, System.cwd!)
-  end
-
-  @doc """
-  Builds a path from `relative_to` to `path`. If `path` is already
-  an absolute path, `relative_to` is ignored. See also `relative_to/2`.
-
-  Unlike `expand/2`, no attempt is made to
-  resolve `..`, `.` or `~`.
-
-  ## Examples
-
-      iex> Path.absname("foo", "bar")
-      "bar/foo"
-
-      iex> Path.absname("../x", "bar")
-      "bar/../x"
-
-  """
-  @spec absname(t, t) :: binary
-  def absname(path, relative_to) do
-    path = IO.chardata_to_string(path)
-    case type(path) do
-      :relative -> absname_join(relative_to, path)
-      :absolute -> absname_join([path])
-      :volumerelative ->
-        relative_to = IO.chardata_to_string(relative_to)
-        absname_vr(split(path), split(relative_to), relative_to)
-    end
-  end
-
-  # Absolute path on current drive
-  defp absname_vr(["/" | rest], [volume | _], _relative),
-    do: absname_join([volume | rest])
-
-  # Relative to current directory on current drive.
-  defp absname_vr([<<x, ?:>> | rest], [<<x, _::binary>> | _], relative),
-    do: absname(absname_join(rest), relative)
-
-  # Relative to current directory on another drive.
-  defp absname_vr([<<x, ?:>> | name], _, _relative) do
-    cwd =
-      case :file.get_cwd([x, ?:]) do
-        {:ok, dir}  -> IO.chardata_to_string(dir)
-        {:error, _} -> <<x, ?:, ?/>>
-      end
-    absname(absname_join(name), cwd)
-  end
-
-  # Joins a list
-  defp absname_join([name1, name2 | rest]), do:
-    absname_join([absname_join(name1, name2) | rest])
-  defp absname_join([name]), do:
-    do_absname_join(IO.chardata_to_string(name), <<>>, [], major_os_type())
-
-  # Joins two paths
-  defp absname_join(left, right),
-    do: do_absname_join(IO.chardata_to_string(left), relative(right), [], major_os_type())
-
-  defp do_absname_join(<<uc_letter, ?:, rest::binary>>, relativename, [], :win32) when uc_letter in ?A..?Z, do:
-    do_absname_join(rest, relativename, [?:, uc_letter+?a-?A], :win32)
-  defp do_absname_join(<<?\\, rest::binary>>, relativename, result, :win32), do:
-    do_absname_join(<<?/, rest::binary>>, relativename, result, :win32)
-  defp do_absname_join(<<?/, rest::binary>>, relativename, [?., ?/ | result], os_type), do:
-    do_absname_join(rest, relativename, [?/ | result], os_type)
-  defp do_absname_join(<<?/, rest::binary>>, relativename, [?/ | result], os_type), do:
-    do_absname_join(rest, relativename, [?/ | result], os_type)
-  defp do_absname_join(<<>>, <<>>, result, os_type), do:
-    IO.iodata_to_binary(reverse_maybe_remove_dir_sep(result, os_type))
-  defp do_absname_join(<<>>, relativename, [?: | rest], :win32), do:
-    do_absname_join(relativename, <<>>, [?: | rest], :win32)
-  defp do_absname_join(<<>>, relativename, [?/ | result], os_type), do:
-    do_absname_join(relativename, <<>>, [?/ | result], os_type)
-  defp do_absname_join(<<>>, relativename, result, os_type), do:
-    do_absname_join(relativename, <<>>, [?/ | result], os_type)
-  defp do_absname_join(<<char, rest::binary>>, relativename, result, os_type), do:
-    do_absname_join(rest, relativename, [char | result], os_type)
-
-  defp reverse_maybe_remove_dir_sep([?/, ?:, letter], :win32), do:
-    [letter, ?:, ?/]
-  defp reverse_maybe_remove_dir_sep([?/], _), do:
-    [?/]
-  defp reverse_maybe_remove_dir_sep([?/ | name], _), do:
-    :lists.reverse(name)
-  defp reverse_maybe_remove_dir_sep(name, _), do:
-    :lists.reverse(name)
-
-  @doc """
-  Converts the path to an absolute one and expands
-  any `.` and `..` characters and a leading `~`.
-
-  ## Examples
-
-      Path.expand("/foo/bar/../bar")
-      #=> "/foo/bar"
-
-  """
-  @spec expand(t) :: binary
-  def expand(path) do
-    expand_dot absname(expand_home(path), System.cwd!)
-  end
-
-  @doc """
-  Expands the path relative to the path given as the second argument
-  expanding any `.` and `..` characters. If the path is already an
-  absolute path, `relative_to` is ignored.
-
-  Note, that this function treats `path` with a leading `~` as
-  an absolute one.
-
-  The second argument is first expanded to an absolute path.
-
-  ## Examples
-
-      # Assuming that the absolute path to baz is /quux/baz
-      Path.expand("foo/bar/../bar", "baz")
-      #=> "/quux/baz/foo/bar"
-
-      Path.expand("foo/bar/../bar", "/baz")
-      "/baz/foo/bar"
-      Path.expand("/foo/bar/../bar", "/baz")
-      "/foo/bar"
-
-  """
-  @spec expand(t, t) :: binary
-  def expand(path, relative_to) do
-    expand_dot absname(absname(expand_home(path), expand_home(relative_to)), System.cwd!)
-  end
-
-  @doc """
-  Returns the path type.
-
-  ## Unix examples
-
-      Path.type("/")                #=> :absolute
-      Path.type("/usr/local/bin")   #=> :absolute
-      Path.type("usr/local/bin")    #=> :relative
-      Path.type("../usr/local/bin") #=> :relative
-      Path.type("~/file")           #=> :relative
-
-  ## Windows examples
-
-      Path.type("D:/usr/local/bin") #=> :absolute
-      Path.type("usr/local/bin")    #=> :relative
-      Path.type("D:bar.ex")         #=> :volumerelative
-      Path.type("/bar/foo.ex")      #=> :volumerelative
-
-  """
-  @spec type(t) :: :absolute | :relative | :volumerelative
-  def type(name) when is_list(name) or is_binary(name) do
-    pathtype(name, major_os_type()) |> elem(0)
-  end
-
-  @doc """
-  Forces the path to be a relative path.
-
-  ## Unix examples
-
-      Path.relative("/usr/local/bin")   #=> "usr/local/bin"
-      Path.relative("usr/local/bin")    #=> "usr/local/bin"
-      Path.relative("../usr/local/bin") #=> "../usr/local/bin"
-
-  ## Windows examples
-
-      Path.relative("D:/usr/local/bin") #=> "usr/local/bin"
-      Path.relative("usr/local/bin")    #=> "usr/local/bin"
-      Path.relative("D:bar.ex")         #=> "bar.ex"
-      Path.relative("/bar/foo.ex")      #=> "bar/foo.ex"
-
-  """
-  @spec relative(t) :: binary
-  def relative(name) do
-    relative(name, major_os_type())
-  end
-
-  defp relative(name, os_type) do
-    pathtype(name, os_type)
-    |> elem(1)
-    |> IO.chardata_to_string
-  end
-
-  defp pathtype(name, os_type) do
-    case os_type do
-      :win32 -> win32_pathtype(name)
-      _      -> unix_pathtype(name)
-    end
-  end
-
-  defp unix_pathtype(<<?/, relative::binary>>), do:
-    {:absolute, relative}
-  defp unix_pathtype([?/ | relative]), do:
-    {:absolute, relative}
-  defp unix_pathtype([list | rest]) when is_list(list), do:
-    unix_pathtype(list ++ rest)
-  defp unix_pathtype(relative), do:
-    {:relative, relative}
-
-  @slash [?/, ?\\]
-
-  defp win32_pathtype([list | rest]) when is_list(list), do:
-    win32_pathtype(list++rest)
-  defp win32_pathtype([char, list | rest]) when is_list(list), do:
-    win32_pathtype([char | list++rest])
-  defp win32_pathtype(<<c1, c2, relative::binary>>) when c1 in @slash and c2 in @slash, do:
-    {:absolute, relative}
-  defp win32_pathtype(<<c, relative::binary>>) when c in @slash, do:
-    {:volumerelative, relative}
-  defp win32_pathtype(<<_letter, ?:, c, relative::binary>>) when c in @slash, do:
-    {:absolute, relative}
-  defp win32_pathtype(<<_letter, ?:, relative::binary>>), do:
-    {:volumerelative, relative}
-
-  defp win32_pathtype([c1, c2 | relative]) when c1 in @slash and c2 in @slash, do:
-    {:absolute, relative}
-  defp win32_pathtype([c | relative]) when c in @slash, do:
-    {:volumerelative, relative}
-  defp win32_pathtype([c1, c2, list | rest]) when is_list(list), do:
-    win32_pathtype([c1, c2 | list++rest])
-  defp win32_pathtype([_letter, ?:, c | relative]) when c in @slash, do:
-    {:absolute, relative}
-  defp win32_pathtype([_letter, ?: | relative]), do:
-    {:volumerelative, relative}
-  defp win32_pathtype(relative), do:
-    {:relative, relative}
-
-  @doc """
-  Returns the given `path` relative to the given `from` path.
-  In other words, it tries to strip the `from` prefix from `path`.
-
-  This function does not query the file system, so it assumes
-  no symlinks between the paths.
-
-  In case a direct relative path cannot be found, it returns
-  the original path.
-
-  ## Examples
-
-      iex> Path.relative_to("/usr/local/foo", "/usr/local")
-      "foo"
-
-      iex> Path.relative_to("/usr/local/foo", "/")
-      "usr/local/foo"
-
-      iex> Path.relative_to("/usr/local/foo", "/etc")
-      "/usr/local/foo"
-
-  """
-  @spec relative_to(t, t) :: binary
-  def relative_to(path, from) do
-    path = IO.chardata_to_string(path)
-    relative_to(split(path), split(from), path)
-  end
-
-  defp relative_to([h | t1], [h | t2], original) do
-    relative_to(t1, t2, original)
-  end
-
-  defp relative_to([_ | _] = l1, [], _original) do
-    join(l1)
-  end
-
-  defp relative_to(_, _, original) do
-    original
-  end
-
-  @doc """
-  Convenience to get the path relative to the current working
-  directory. If, for some reason, the current working directory
-  cannot be retrieved, returns the full path.
-  """
-  @spec relative_to_cwd(t) :: binary
-  def relative_to_cwd(path) do
-    case :file.get_cwd do
-      {:ok, base} -> relative_to(path, IO.chardata_to_string(base))
-      _ -> path
-    end
-  end
-
-  @doc """
-  Returns the last component of the path or the path
-  itself if it does not contain any directory separators.
-
-  ## Examples
-
-      iex> Path.basename("foo")
-      "foo"
-
-      iex> Path.basename("foo/bar")
-      "bar"
-
-      iex> Path.basename("/")
-      ""
-
-  """
-  @spec basename(t) :: binary
-  def basename(path) do
-    FN.basename(IO.chardata_to_string(path))
-  end
-
-  @doc """
-  Returns the last component of `path` with the `extension`
-  stripped. This function should be used to remove a specific
-  extension which may, or may not, be there.
-
-  ## Examples
-
-      iex> Path.basename("~/foo/bar.ex", ".ex")
-      "bar"
-
-      iex> Path.basename("~/foo/bar.exs", ".ex")
-      "bar.exs"
-
-      iex> Path.basename("~/foo/bar.old.ex", ".ex")
-      "bar.old"
-
-  """
-  @spec basename(t, t) :: binary
-  def basename(path, extension) do
-    FN.basename(IO.chardata_to_string(path), IO.chardata_to_string(extension))
-  end
-
-  @doc """
-  Returns the directory component of `path`.
-
-  ## Examples
-
-      iex> Path.dirname("/foo/bar.ex")
-      "/foo"
-
-      iex> Path.dirname("/foo/bar/baz.ex")
-      "/foo/bar"
-
-  """
-  @spec dirname(t) :: binary
-  def dirname(path) do
-    FN.dirname(IO.chardata_to_string(path))
-  end
-
-  @doc """
-  Returns the extension of the last component of `path`.
-
-  ## Examples
-
-      iex> Path.extname("foo.erl")
-      ".erl"
-
-      iex> Path.extname("~/foo/bar")
-      ""
-
-  """
-  @spec extname(t) :: binary
-  def extname(path) do
-    FN.extension(IO.chardata_to_string(path))
-  end
-
-  @doc """
-  Returns the `path` with the `extension` stripped.
-
-  ## Examples
-
-      iex> Path.rootname("/foo/bar")
-      "/foo/bar"
-
-      iex> Path.rootname("/foo/bar.ex")
-      "/foo/bar"
-
-  """
-  @spec rootname(t) :: binary
-  def rootname(path) do
-    FN.rootname(IO.chardata_to_string(path))
-  end
-
-  @doc """
-  Returns the `path` with the `extension` stripped. This function should be used to
-  remove a specific extension which might, or might not, be there.
-
-  ## Examples
-
-      iex> Path.rootname("/foo/bar.erl", ".erl")
-      "/foo/bar"
-
-      iex> Path.rootname("/foo/bar.erl", ".ex")
-      "/foo/bar.erl"
-
-  """
-  @spec rootname(t, t) :: binary
-  def rootname(path, extension) do
-    FN.rootname(IO.chardata_to_string(path), IO.chardata_to_string(extension))
-  end
-
-  @doc """
-  Joins a list of paths.
-
-  This function should be used to convert a list of paths to a path.
-  Note that any trailing slash is removed when joining.
-
-  ## Examples
-
-      iex> Path.join(["~", "foo"])
-      "~/foo"
-
-      iex> Path.join(["foo"])
-      "foo"
-
-      iex> Path.join(["/", "foo", "bar/"])
-      "/foo/bar"
-
-  """
-  @spec join(nonempty_list(t)) :: binary
-  def join([name1, name2 | rest]), do:
-    join([join(name1, name2) | rest])
-  def join([name]), do:
-    IO.chardata_to_string(name)
-
-  @doc """
-  Joins two paths.
-
-  The right path will always be expanded to its relative format
-  and any trailing slash is removed on join.
-
-  ## Examples
-
-      iex> Path.join("foo", "bar")
-      "foo/bar"
-
-  """
-  @spec join(t, t) :: binary
-  def join(left, right) do
-    left    = IO.chardata_to_string(left)
-    os_type = major_os_type()
-    do_join(left, right, os_type) |> remove_dir_sep(os_type)
-  end
-
-  defp do_join("", right, os_type),   do: relative(right, os_type)
-  defp do_join("/", right, os_type),  do: "/" <> relative(right, os_type)
-  defp do_join(left, right, os_type), do: remove_dir_sep(left, os_type) <> "/" <> relative(right, os_type)
-
-  defp remove_dir_sep("", _os_type), do: ""
-  defp remove_dir_sep("/", _os_type), do: "/"
-  defp remove_dir_sep(bin, os_type) do
-    last = :binary.last(bin)
-    if last == ?/ or (last == ?\\ and os_type == :win32) do
-      binary_part(bin, 0, byte_size(bin) - 1)
-    else
-      bin
-    end
-  end
-
-  @doc ~S"""
-  Splits the path into a list at the path separator.
-
-  If an empty string is given, returns an empty list.
-
-  On Windows, path is split on both "\" and "/" separators
-  and the driver letter, if there is one, is always returned
-  in lowercase.
-
-  ## Examples
-
-      iex> Path.split("")
-      []
-
-      iex> Path.split("foo")
-      ["foo"]
-
-      iex> Path.split("/foo/bar")
-      ["/", "foo", "bar"]
-
-  """
-  @spec split(t) :: [binary]
-
-  # Work around a bug in Erlang on UNIX
-  def split(""), do: []
-
-  def split(path) do
-    FN.split(IO.chardata_to_string(path))
-  end
-
-  defmodule Wildcard do
-    @moduledoc false
-
-    def read_link_info(file) do
-      call({:read_link_info, file})
-    end
-
-    def list_dir(dir) do
-      case call({:list_dir, dir}) do
-        {:ok, files} ->
-          {:ok, for(file <- files, hd(file) != ?., do: file)}
-        other ->
-          other
-      end
-    end
-
-    @compile {:inline, call: 1}
-
-    defp call(tuple) do
-      x = :erlang.dt_spread_tag(true)
-      y = :gen_server.call(:file_server_2, tuple)
-      :erlang.dt_restore_tag(x)
-      y
-    end
-  end
-
-  @doc """
-  Traverses paths according to the given `glob` expression, and returns a
-  list of matches.
-
-  The wildcard looks like an ordinary path, except that certain
-  "wildcard characters" are interpreted in a special way. The
-  following characters are special:
-
-    * `?` - matches one character
-
-    * `*` - matches any number of characters up to the end of the filename, the
-      next dot, or the next slash
-
-    * `**` - two adjacent `*`'s used as a single pattern will match all
-      files and zero or more directories and subdirectories
-
-    * `[char1,char2,...]` - matches any of the characters listed; two
-      characters separated by a hyphen will match a range of characters.
-      Do not add spaces before and after the comma as it would then match
-      paths containing the space character itself.
-
-    * `{item1,item2,...}` - matches one of the alternatives
-      Do not add spaces before and after the comma as it would then match
-      paths containing the space character itself.
-
-  Other characters represent themselves. Only paths that have
-  exactly the same character in the same position will match. Note
-  that matching is case-sensitive; i.e. "a" will not match "A".
-
-  By default, the patterns `*` and `?` do not match files starting
-  with a dot `.` unless `match_dot: true` is given in `opts`.
-
-  ## Examples
-
-  Imagine you have a directory called `projects` with three Elixir projects
-  inside of it: `elixir`, `ex_doc` and `dynamo`. You can find all `.beam` files
-  inside the `ebin` directory of each project as follows:
-
-      Path.wildcard("projects/*/ebin/**/*.beam")
-
-  If you want to search for both `.beam` and `.app` files, you could do:
-
-      Path.wildcard("projects/*/ebin/**/*.{beam,app}")
-
-  """
-  @spec wildcard(t, Keyword.t) :: [binary]
-  def wildcard(glob, opts \\ []) do
-    mod = if Keyword.get(opts, :match_dot), do: :file, else: Path.Wildcard
-    glob
-    |> chardata_to_list()
-    |> :filelib.wildcard(mod)
-    |> Enum.map(&IO.chardata_to_string/1)
-  end
-
-  # expand_dot the given path by expanding "..", "." and "~".
-
-  defp chardata_to_list(chardata) do
-    case :unicode.characters_to_list(chardata) do
-      result when is_list(result) ->
-        result
-
-      {:error, encoded, rest} ->
-        raise UnicodeConversionError, encoded: encoded, rest: rest, kind: :invalid
-
-      {:incomplete, encoded, rest} ->
-        raise UnicodeConversionError, encoded: encoded, rest: rest, kind: :incomplete
-    end
-  end
-
-  defp expand_home(type) do
-    case IO.chardata_to_string(type) do
-      "~" <> rest -> resolve_home(rest)
-      rest        -> rest
-    end
-  end
-
-  defp resolve_home(""), do: System.user_home!
-
-  defp resolve_home(rest) do
-    case {rest, major_os_type()} do
-      {"\\" <> _, :win32} ->
-        System.user_home! <> rest
-      {"/" <> _, _} ->
-        System.user_home! <> rest
-      _ -> rest
-    end
-  end
-
-  defp expand_dot(<<"/", rest::binary>>),
-    do: "/" <> do_expand_dot(rest)
-  defp expand_dot(<<letter, ":/", rest::binary>>) when letter in ?a..?z,
-    do: <<letter, ":/">> <> do_expand_dot(rest)
-  defp expand_dot(path),
-    do: do_expand_dot(path)
-
-  defp do_expand_dot(path),
-    do: do_expand_dot(:binary.split(path, "/", [:global]), [])
-
-  defp do_expand_dot([".." | t], [_, _ | acc]),
-    do: do_expand_dot(t, acc)
-  defp do_expand_dot([".." | t], []),
-    do: do_expand_dot(t, [])
-  defp do_expand_dot(["." | t], acc),
-    do: do_expand_dot(t, acc)
-  defp do_expand_dot([h | t], acc),
-    do: do_expand_dot(t, ["/", h | acc])
-  defp do_expand_dot([], []),
-    do: ""
-  defp do_expand_dot([], ["/" | acc]),
-    do: IO.iodata_to_binary(:lists.reverse(acc))
-
-  defp major_os_type do
-    :os.type |> elem(0)
-  end
-end
@@ -1,269 +1,68 @@
 defmodule Port do
-  @moduledoc ~S"""
-  Functions for interacting with the external world through ports.
-
-  Ports provide a mechanism to start operating system processes external
-  to the Erlang VM and communicate with them via message passing.
-
-  ## Example
-
-      iex> port = Port.open({:spawn, "cat"}, [:binary])
-      iex> send port, {self(), {:command, "hello"}}
-      iex> send port, {self(), {:command, "world"}}
-      iex> flush()
-      {#Port<0.1444>, {:data, "hello"}}
-      {#Port<0.1444>, {:data, "world"}}
-      iex> send port, {self(), :close}
-      :ok
-      iex> flush()
-      {#Port<0.1464>, :closed}
-      :ok
-
-  In the example above, we have created a new port that executes the
-  program `cat`. `cat` is a program available on UNIX systems that
-  receives data from multiple inputs and concatenates them in the output.
-
-  After the port was created, we sent it two commands in the form of
-  messages using `Kernel.send/2`. The first command has the binary payload
-  of "hello" and the second has "world".
-
-  After sending those two messages, we invoked the IEx helper `flush()`,
-  which printed all messages received from the port, in this case we got
-  "hello" and "world" back. Notice the messages are in binary because we
-  passed the `:binary` option when opening the port in `Port.open/2`. Without
-  such option, it would have yielded a list of bytes.
-
-  Once everything was done, we closed the port.
-
-  Elixir provides many conveniences for working with ports and some drawbacks.
-  We will explore those below.
-
-  ## Message and function APIs
-
-  There are two APIs for working with ports. It can be either asynchronous via
-  message passing, as in the example above, or by calling the functions on this
-  module.
-
-  The messages supported by ports and their counterpart function APIs are
-  listed below:
-
-    * `{pid, {:command, binary}}` - sends the given data to the port.
-      See `command/3`.
-
-    * `{pid, :close}` - closes the port. Unless the port is already closed,
-      the port will reply with `{port, :closed}` message once it has flushed
-      its buffers and effectively closed. See `close/1`.
-
-    * `{pid, {:connect, new_pid}}` - sets the `new_pid` as the new owner of
-      the port. Once a port is opened, the port is linked and connected to the
-      caller process and communication to the port only happens through the
-      connected process. This message makes `new_pid` the new connected processes.
-      Unless the port is dead, the port will reply to the old owner with
-      `{port, :connected}`. See `connect/2`.
-
-  On its turn, the port will send the connected process the following messages:
-
-    * `{port, {:port, data}}` - data sent by the port
-    * `{port, :closed}` - reply to the `{pid, :close}` message
-    * `{port, :connected}` - reply to the `{pid, {:connect, new_pid}}` message
-    * `{:EXIT, port, reason}` - exit signals in case the port crashes and the
-      owner process is trapping exits
-
-  ## Open mechanisms
-
-  The port can be opened through four main mechanisms.
-
-  As a short summary, prefer to using the `:spawn` and `:spawn_executable`
-  options mentioned below. The other two options, `:spawn_driver` and `:fd`
-  are for advanced usage within the VM. Also consider using `System.cmd/3`
-  if all you want is to execute a program and retrieve its return value.
-
-  ### spawn
-
-  The `:spawn` tuple receives a binary that is going to be executed as a
-  full invocation. For example, we can use it to invoke "echo hello" directly:
-
-      iex> port = Port.open({:spawn, "echo oops"}, [:binary])
-      iex> flush()
-      {#Port<0.1444>, {:data, "oops\n"}}
-
-  `:spawn` will retrieve the program name from the argument and traverse your
-  OS `$PATH` environment variable looking for a matching program.
-
-  Although the above is handy, it means it is impossible to invoke an executable
-  that has whitespaces on its name or in any of its arguments. For those reasons,
-  most times it is preferrable to execute `:spawn_executable`.
-
-  ### spawn_executable
-
-  Spawn executable is a more restricted and explicit version of spawn. It expects
-  full file paths to the executable you want to execute. If they are in your `$PATH`,
-  they can be retrieved by calling `System.find_executable/1`:
-
-      iex> path = System.find_executable("echo")
-      iex> port = Port.open({:spawn_executable, path}, [:binary, args: ["hello world"]])
-      iex> flush()
-      {#Port<0.1380>, {:data, "hello world\n"}}
-
-  When using `:spawn_executable`, the list of arguments can be passed via
-  the `:args` option as done above. For the full list of options, see the
-  documentation for the Erlang function `:erlang.open_port/2`.
-
-  ### spawn_driver
-
-  Spawn driver is used to start Port Drivers, which are programs written in
-  C that implements a specific communication protocols and are dynamically
-  linked to the Erlang VM. Port drivers are an advanced topic and one of the
-  mechanisms for integrating C code, alongside NIFs. For more information,
-  [please check the Erlang docs](http://erlang.org/doc/reference_manual/ports.html).
-
-  ### fd
-
-  The `:fd` name option allows developers to access `in` and `out` file
-  descriptors used by the Erlang VM. You would use those only if you are
-  reimplementing core part of the Runtime System, such as the `:user` and
-  `:shell` processes.
-
-  ## Zombie processes
-
-  A port can be closed via the `close/1` function or by sending a `{pid, :close}`
-  message. However, if the VM crashes, a long-running program started by the port
-  will have its stdin and stdout channels closed but **it won't be automatically
-  terminated**.
-
-  While most UNIX command line tools will exit once its communication channels
-  are closed, not all command line applications will do so. While we encourage
-  graceful termination by detecting if stdin/stdout has been closed, we do not
-  always have control over how 3rd party software terminates. In those cases,
-  you can wrap the application in a script that checks for stdin. Here is such
-  script in bash:
-
-      #!/bin/sh
-      "$@"
-      pid=$!
-      while read line ; do
-        :
-      done
-      kill -KILL $pid
-
-
-  Now instead of:
-
-      Port.open({:spawn_executable, "/path/to/program"},
-                [args: ["a", "b", "c"]])
-
-  You may invoke:
-
-      Port.open({:spawn_executable, "/path/to/wrapper"},
-                [args: ["/path/to/program", "a", "b", "c"]])
-
+  @moduledoc """
+  Functions related to Erlang ports.
  """

-  @type name :: {:spawn, charlist | binary} |
-                {:spawn_driver, charlist | binary} |
-                {:spawn_executable, charlist | atom} |
-                {:fd, non_neg_integer, non_neg_integer}
-
  @doc """
-  Opens a port given a tuple `name` and a list of `options`.
-
-  The module documentation above contains documentation and examples
-  for the supported `name` values, summarized below:
-
-    * `{:spawn, command}` - runs an external program. `command` must contain
-      the program name and optionally a list of arguments separated by space.
-      If passing programs or arguments with space in their name, use the next option.
-    * `{:spawn_executable, filename}` - runs the executable given by the absolute
-      file name `filename`. Arguments can be passed via the `:args` option.
-    * `{:spawn_driver, command}` - spawns so-called port drivers.
-    * `{:fd, fd_in, fd_out}` - accesses file descriptors, `fd_in` and `fd_out`
-      opened by the VM.
-
-  For more information and the list of options, see
-  [`:erlang.open_port/2`](http://www.erlang.org/doc/man/erlang.html#open_port-2).
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#open_port-2.
  """
-  @spec open(name, list) :: port
  def open(name, settings) do
    :erlang.open_port(name, settings)
  end

  @doc """
-  Closes the `port`.
-
-  For more information, see [`:erlang.port_close/1`](http://www.erlang.org/doc/man/erlang.html#port_close-1).
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#port_close-1.
  """
-  @spec close(port) :: true
  def close(port) do
    :erlang.port_close(port)
  end

  @doc """
-  Sends `data` to the port driver `port`.
-
-  For more information, see [`:erlang.port_command/2`](http://www.erlang.org/doc/man/erlang.html#port_command-2).
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#port_command-2.
  """
-  @spec command(port, iodata, [:force | :nosuspend]) :: boolean
-  def command(port, data, options \\ []) do
+  def command(port, data, options // []) do
    :erlang.port_command(port, data, options)
  end

  @doc """
-  Associates the `port` identifier with a `pid`.
-
-  For more information, see [`:erlang.port_connect/2`](http://www.erlang.org/doc/man/erlang.html#port_connect-2).
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#port_connect-2.
  """
-  @spec connect(port, pid) :: true
  def connect(port, pid) do
    :erlang.port_connect(port, pid)
  end

  @doc """
-  Returns information about the `port` or `nil` if the port is closed.
+  See http://www.erlang.org/doc/man/erlang.html#port_control-3.
+  """
+  def control(port, operation, data) do
+    :erlang.port_control(port, operation, data)
+  end

-  For more information, see [`:erlang.port_info/1`](http://www.erlang.org/doc/man/erlang.html#port_info-1).
+  @doc """
+  See http://www.erlang.org/doc/man/erlang.html#port_call-3.
+  """
+  def call(port, operation, data) do
+    :erlang.port_call(port, operation, data)
+  end
+
+  @doc """
+  See http://www.erlang.org/doc/man/erlang.html#port_info-1.
  """
  def info(port) do
-    nillify :erlang.port_info(port)
+    :erlang.port_info(port)
  end

  @doc """
-  Returns information about the `port` or `nil` if the port is closed.
-
-  For more information, see [`:erlang.port_info/2`](http://www.erlang.org/doc/man/erlang.html#port_info-2).
+  See http://www.erlang.org/doc/man/erlang.html#port_info-2.
  """
-  @spec info(port, atom) :: {atom, term} | nil
-  def info(port, spec)
-
-  def info(port, :registered_name) do
-    case :erlang.port_info(port, :registered_name) do
-      [] -> {:registered_name, []}
-      other -> nillify(other)
-    end
-  end
-
  def info(port, item) do
-    nillify :erlang.port_info(port, item)
+    :erlang.port_info(port, item)
  end

  @doc """
-  Returns a list of all ports in the current node.
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#ports-0.
  """
-  @spec list :: [port]
  def list do
    :erlang.ports
  end
-
-  @compile {:inline, nillify: 1}
-  defp nillify(:undefined), do: nil
-  defp nillify(other),      do: other
-end
+end
@@ -1,48 +1,43 @@
 defmodule Process do
  @moduledoc """
-  Conveniences for working with processes and the process dictionary.
-
-  Besides the functions available in this module, the `Kernel` module
-  exposes and auto-imports some basic functionality related to processes
-  available through the functions:
-
-    * `Kernel.spawn/1` and `Kernel.spawn/3`
-    * `Kernel.spawn_link/1` and `Kernel.spawn_link/3`
-    * `Kernel.spawn_monitor/1` and `Kernel.spawn_monitor/3`
-    * `Kernel.self/0`
-    * `Kernel.send/2`
-
+  This module provides convenience functions around processes and
+  the process dictionary. In Erlang, most of these functions are
+  auto-imported, but in Elixir they are grouped in a module for
+  convenience. Notice that these functions, different from Erlang's,
+  always return nil instead of undefined. You can use their Erlang
+  version if you want the undefined value.
  """

  @doc """
-  Returns `true` if the process exists and is alive (i.e. it is not exiting
-  and has not exited yet). Otherwise, returns `false`.
+  Returns true if the process exists and is alive, that is,
+  is not exiting and has not exited. Otherwise, returns false.

  `pid` must refer to a process at the local node.
-
-  Inlined by the compiler.
  """
-  @spec alive?(pid) :: boolean
  def alive?(pid) do
    :erlang.is_process_alive(pid)
  end

  @doc """
-  Returns all key-value pairs in the process dictionary.
+  Returns the current process.
+  """
+  def self do
+    :erlang.self()
+  end

-  Inlined by the compiler.
+  @doc """
+  Returns all key-values in the dictionary
+  with no specific ordering (i.e. they are
+  not a keywords list).
  """
-  @spec get :: [{term, term}]
  def get do
    :erlang.get()
  end

  @doc """
-  Returns the value for the given `key` or `default` if `key` is not set.
+  Returns the value for the given key.
  """
-  @spec get(term) :: term
-  @spec get(term, default :: term) :: term
-  def get(key, default \\ nil) do
+  def get(key, default // nil) do
    case :erlang.get(key) do
      :undefined ->
        default
@@ -51,320 +46,139 @@ defmodule Process do
    end
  end

-  @doc """
-  Returns all keys in the process dictionary.
-
-  Inlined by the compiler.
-  """
-  @spec get_keys() :: [term]
-  def get_keys() do
-    :erlang.get_keys()
-  end
-
  @doc """
  Returns all keys that have the given `value`.
-
-  Inlined by the compiler.
  """
-  @spec get_keys(term) :: [term]
  def get_keys(value) do
    :erlang.get_keys(value)
  end

  @doc """
-  Stores the given `key`-`value` pair in the process dictionary.
-
-  The return value is the value that was previously stored under the key `key`
-  (or `nil` in case no value was stored under `key`).
+  Stores the given key-value in the process dictionary.
  """
-  @spec put(term, term) :: term | nil
  def put(key, value) do
    nillify :erlang.put(key, value)
  end

  @doc """
-  Deletes the given `key` from the process dictionary.
+  Deletes all items in the dictionary.
+  """
+  def delete() do
+    :erlang.erase()
+  end
+
+  @doc """
+  Deletes the given key from the dictionary.
  """
-  @spec delete(term) :: term | nil
  def delete(key) do
    nillify :erlang.erase(key)
  end

  @doc """
-  Sends an exit signal with the given `reason` to the `pid`.
+  Sends an exit signal with the given reason to the pid.

-  The following behaviour applies if `reason` is any term except `:normal`
-  or `:kill`:
+  The following behavior apply if reason is any term except `:normal` or `:kill`:

-    1. If `pid` is not trapping exits, `pid` will exit with the given
-       `reason`.
+  1) If pid is not trapping exits, pid itself will exist with the given reason;

-    2. If `pid` is trapping exits, the exit signal is transformed into a
-       message `{:EXIT, from, reason}` and delivered to the message queue
-       of `pid`.
+  2) If pid is trapping exits, the exit signal is transformed into a message
+     {'EXIT', from, reason} and delivered to the message queue of pid;

-  If `reason` is the atom `:normal`, `pid` will not exit (unless `pid` is
-  the calling process, in which case it will exit with the reason `:normal`).
-  If it is trapping exits, the exit signal is transformed into a message
-  `{:EXIT, from, :normal}` and delivered to its message queue.
+  3) If reason is the atom `:normal`, pid will not exit. If it is trapping exits,
+     the exit signal is transformed into a message {'EXIT', from, :normal} and
+     delivered to its message queue;

-  If `reason` is the atom `:kill`, that is if `exit(pid, :kill)` is called,
-  an untrappable exit signal is sent to `pid` which will unconditionally exit
-  with reason `:killed`.
-
-  Inlined by the compiler.
+  4) If reason is the atom `:kill`, that is if `exit(pid, :kill)` is called, an
+     untrappable exit signal is sent to pid which will unconditionally exit with
+     exit reason `:killed`.

  ## Examples

      Process.exit(pid, :kill)

  """
-  @spec exit(pid, term) :: true
-  def exit(pid, reason) do
-    :erlang.exit(pid, reason)
+  def exit(pid, status) do
+    :erlang.exit(pid, status)
  end

  @doc """
-  Sleeps the current process by `timeout`.
-
-  `timeout` is either the number of milliseconds to sleep as an
-  integer or the atom `:infinity`. When `:infinity` is given,
-  the current process will suspend forever.
-
-  **Use this function with extreme care**. For almost all situations
-  where you would use `sleep/1` in Elixir, there is likely a
-  more correct, faster and precise way of achieving it with
-  message passing.
-
-  For example, if you are waiting a process to perform some
-  action, it is better to communicate.
-
-  In other words, **do not**:
-
-      Task.start_link fn ->
-        do_something()
-        ...
-      end
-
-      # Wait until work is done
-      Process.sleep(2000)
-
-  But **do**:
-
-      parent = self()
-      Task.start_link fn ->
-        do_something()
-        send parent, :work_is_done
-        ...
-      end
-
-      receive do
-        :work_is_done -> :ok
-      after
-        30_000 -> :timeout # Optional timeout
-      end
-
-  Or even use `Task.async/1` and `Task.await/2` in the example
-  above.
-
-  Similarly, if you are waiting for a process to terminate,
-  use monitor instead of sleep. **Do not**:
-
-      Task.start_link fn ->
-        ...
-      end
-
-      # Wait until task terminates
-      Process.sleep(2000)
-
-  Instead **do**:
-
-      {:ok, pid} =
-        Task.start_link fn ->
-          ...
-        end
-
-      ref = Process.monitor(pid)
-      receive do
-        {:DOWN, ^ref, _, _, _} -> :task_is_down
-      after
-        30_000 -> :timeout # Optional timeout
-      end
+  Returns the pid of a new process started by the application of `fun`.

+  It behaves exactly the same as the `Kernel.spawn/1` function except
+  it also accepts extra options, for the list of available options
+  check http://www.erlang.org/doc/man/erlang.html#spawn_opt-4
  """
-  def sleep(timeout)
-      when is_integer(timeout) and timeout >= 0
-      when timeout == :infinity do
-    receive after: (timeout -> :ok)
-  end
-
-  @doc """
-  Sends a message to the given process.
-
-  If the option `:noconnect` is used and sending the message would require an
-  auto-connection to another node the message is not sent and `:noconnect` is
-  returned.
-
-  If the option `:nosuspend` is used and sending the message would cause the
-  sender to be suspended the message is not sent and `:nosuspend` is returned.
-
-  Otherwise the message is sent and `:ok` is returned.
-
-  ## Examples
-
-      iex> Process.send({:name, :node_does_not_exist}, :hi, [:noconnect])
-      :noconnect
-
-  """
-  @spec send(dest, msg, [option]) :: :ok | :noconnect | :nosuspend
-        when dest: pid | port | atom | {atom, node},
-             msg: any,
-             option: :noconnect | :nosuspend
-  def send(dest, msg, options) do
-    :erlang.send(dest, msg, options)
-  end
-
-  @doc """
-  Sends `msg` to `dest` after `time` milliseconds.
-
-  If `dest` is a PID, it must be the PID of a local process, dead or alive.
-  If `dest` is an atom, it must be the name of a registered process
-  which is looked up at the time of delivery. No error is given if the name does
-  not refer to a process.
-
-  This function returns a timer reference, which can be read or canceled with
-  `read_timer/1` and `cancel_timer/1`.
-
-  Finally, the timer will be automatically canceled if the given `dest` is a PID
-  which is not alive or when the given PID exits. Note that timers will not be
-  automatically canceled when `dest` is an atom (as the atom resolution is done
-  on delivery).
-
-  ## Options
-
-    * `:abs` - (boolean) when `false`, `time` is treated as relative to the
-    current monotonic time. When `true`, `time` is the absolute value of the
-    Erlang monotonic time at which `msg` should be delivered to `dest`.
-    To read more about Erlang monotonic time and other time-related concepts,
-    look at the documentation for the `System` module. Defaults to `false`.
-
-  """
-  @spec send_after(pid | atom, term, non_neg_integer, [option]) :: reference
-        when option: {:abs, boolean}
-  def send_after(dest, msg, time, opts \\ []) do
-    :erlang.send_after(time, dest, msg, opts)
-  end
-
-  @doc """
-  Cancels a timer created by `send_after/3`.
-
-  When the result is an integer, it represents the time in milliseconds
-  left until the timer would have expired.
-
-  When the result is `false`, a timer corresponding to `timer_ref` could
-  not be found. This can be either because the timer expired, already has
-  been canceled, or because `timer_ref` never corresponded to a timer.
-
-  If the timer has expired, the timeout message has been sent, but it does
-  not tell you whether or not it has arrived at its destination yet.
-
-  Inlined by the compiler.
-  """
-  @spec cancel_timer(reference) :: non_neg_integer | false
-  def cancel_timer(timer_ref) do
-    :erlang.cancel_timer(timer_ref)
-  end
-
-  @doc """
-  Reads a timer created by `send_after/3`.
-
-  When the result is an integer, it represents the time in milliseconds
-  left until the timer will expire.
-
-  When the result is `false`, a timer corresponding to `timer_ref` could
-  not be found. This can be either because the timer expired, already has
-  been canceled, or because `timer_ref` never corresponded to a timer.
-
-  If the timer has expired, the timeout message has been sent, but it does
-  not tell you whether or not it has arrived at its destination yet.
-
-  Inlined by the compiler.
-  """
-  @spec read_timer(reference) :: non_neg_integer | false
-  def read_timer(timer_ref) do
-    :erlang.read_timer(timer_ref)
-  end
-
-  @type spawn_opt  :: :link | :monitor | {:priority, :low | :normal | :high} |
-                      {:fullsweep_after, non_neg_integer} |
-                      {:min_heap_size, non_neg_integer} |
-                      {:min_bin_vheap_size, non_neg_integer}
-  @type spawn_opts :: [spawn_opt]
-
-  @doc """
-  Spawns the given function according to the given options.
-
-  The result depends on the given options. In particular,
-  if `:monitor` is given as an option, it will return a tuple
-  containing the PID and the monitoring reference, otherwise
-  just the spawned process PID.
-
-  It also accepts extra options, for the list of available options
-  check [`:erlang.spawn_opt/4`](http://www.erlang.org/doc/man/erlang.html#spawn_opt-4).
-
-  Inlined by the compiler.
-  """
-  @spec spawn((() -> any), spawn_opts) :: pid | {pid, reference}
-  def spawn(fun, opts) do
+  def spawn(fun, opts // []) do
    :erlang.spawn_opt(fun, opts)
  end

  @doc """
-  Spawns the given function from module `mod`, passing the given `args`
-  according to the given options.
+  Returns the pid of a new process started by the application of
+  `module.function(args)`. The new process created will be placed in the system
+  scheduler queue and be run some time later.

-  The result depends on the given options. In particular,
-  if `:monitor` is given as an option, it will return a tuple
-  containing the PID and the monitoring reference, otherwise
-  just the spawned process PID.
+  It behaves exactly the same as the `Kernel.spawn/3` function except
+  it also accepts extra options, for the list of available options
+  check http://www.erlang.org/doc/man/erlang.html#spawn_opt-4

-  It also accepts extra options, for the list of available options
-  check [`:erlang.spawn_opt/4`](http://www.erlang.org/doc/man/erlang.html#spawn_opt-4).
-
-  Inlined by the compiler.
  """
-  @spec spawn(module, atom, list, spawn_opts) :: pid | {pid, reference}
-  def spawn(mod, fun, args, opts) do
+  def spawn(mod, fun, args, opts // []) do
    :erlang.spawn_opt(mod, fun, args, opts)
  end

  @doc """
-  The calling process starts monitoring the given `item`.
+  Returns the pid of a new process started by the application of `fun`.
+  A link is created between the calling process and the new
+  process, atomically.
+  """
+  def spawn_link(fun) do
+    :erlang.spawn_link(fun)
+  end
+
+  @doc """
+  Returns the pid of a new process started by the application of
+  `module.function(args)`. A link is created between the calling process
+  and the new process, atomically. Otherwise works like spawn/3.
+  """
+  def spawn_link(mod, fun, args) do
+    :erlang.spawn_link(mod, fun, args)
+  end
+
+  @doc """
+  Returns the pid of a new process started by the application of `fun`
+  and reference for a monitor created to the new process.
+  """
+  def spawn_monitor(fun) do
+    :erlang.spawn_monitor(fun)
+  end
+
+  @doc """
+  A new process is started by the application of `module.function(args)`
+  and the process is monitored at the same time. Returns the pid and a
+  reference for the monitor. Otherwise works like spawn/3.
+  """
+  def spawn_monitor(mod, fun, args) do
+    :erlang.spawn_monitor(mod, fun, args)
+  end
+
+  @doc """
+  The calling process starts monitoring the item given.
  It returns the monitor reference.

-  See [the need for monitoring](http://elixir-lang.org/getting-started/mix-otp/genserver.html#the-need-for-monitoring)
-  for an example.
-  See [`:erlang.monitor/2`](http://www.erlang.org/doc/man/erlang.html#monitor-2) for more info.
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#monitor-2 for more info.
  """
-  @spec monitor(pid | {reg_name :: atom, node :: atom} | reg_name :: atom) :: reference
  def monitor(item) do
    :erlang.monitor(:process, item)
  end

  @doc """
-  If `monitor_ref` is a reference which the calling process
-  obtained by calling `monitor/1`, this monitoring is turned off.
+  If monitor_ref is a reference which the calling process
+  obtained by calling monitor/1, this monitoring is turned off.
  If the monitoring is already turned off, nothing happens.

-  See [`:erlang.demonitor/2`](http://www.erlang.org/doc/man/erlang.html#demonitor-2) for more info.
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#demonitor-2 for more info.
  """
-  @spec demonitor(reference) :: true
-  @spec demonitor(reference, options :: [:flush | :info]) :: boolean
-  def demonitor(monitor_ref, options \\ []) do
+  def demonitor(monitor_ref, options // []) do
    :erlang.demonitor(monitor_ref, options)
  end

@@ -373,12 +187,11 @@ defmodule Process do
  processes currently existing on the local node.

  Note that a process that is exiting, exists but is not alive, i.e.,
-  `alive?/1` will return `false` for a process that is exiting,
+  alive?/1 will return false for a process that is exiting,
  but its process identifier will be part of the result returned.

-  See [`:erlang.processes/0`](http://www.erlang.org/doc/man/erlang.html#processes-0) for more info.
+  See http://www.erlang.org/doc/man/erlang.html#processes-0 for more info.
  """
-  @spec list :: [pid]
  def list do
    :erlang.processes()
  end
@@ -387,182 +200,91 @@ defmodule Process do
  Creates a link between the calling process and another process
  (or port) `pid`, if there is not such a link already.

-  See [`:erlang.link/1`](http://www.erlang.org/doc/man/erlang.html#link-1) for more info.
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#link-1 for more info.
  """
-  @spec link(pid | port) :: true
  def link(pid) do
    :erlang.link(pid)
  end

  @doc """
  Removes the link, if there is one, between the calling process and
-  the process or port referred to by `pid`. Returns `true` and does not
+  the process or port referred to by `pid`. Returns true and does not
  fail, even if there is no link or `id` does not exist

-  See [`:erlang.unlink/1`](http://www.erlang.org/doc/man/erlang.html#unlink-1) for more info.
-
-  Inlined by the compiler.
+  See http://www.erlang.org/doc/man/erlang.html#unlink-1 for more info.
  """
-  @spec unlink(pid | port) :: true
  def unlink(pid) do
    :erlang.unlink(pid)
  end

  @doc """
-  Registers the given `pid_or_port` under the given `name`.
+  Associates the name with a pid or a port identifier. name, which must
+  be an atom, can be used instead of the pid / port identifier in the
+  send operator (name <- message).

-  `name` must be an atom and can then be used instead of the
-  PID/port identifier when sending messages with `Kernel.send/2`.
-
-  `register/2` will fail with `ArgumentError` if the PID/Port is
-  not existing locally and alive, if the name is already registered
-  or if the `pid_or_port` is already registered to a different `name`.
-
-  The following names are reserved and cannot be assigned to
-  processes nor ports: `nil`, `false`, `true` or `:undefined`.
+  See http://www.erlang.org/doc/man/erlang.html#register-2 for more info.
  """
-  @spec register(pid | port, atom) :: true
-  def register(pid_or_port, name) when is_atom(name) and not name in [nil, false, true, :undefined] do
-    :erlang.register(name, pid_or_port)
-  catch
-    :error, :badarg when node(pid_or_port) != node()  ->
-      message = "could not register the #{pid_or_port pid_or_port} because it belongs to another node"
-      :erlang.error ArgumentError.exception(message), [pid_or_port, name]
-    :error, :badarg ->
-      message = "could not register the #{pid_or_port pid_or_port} with " <>
-                "name #{inspect name}. Or it is not alive, or the name is already " <>
-                "taken, or it has already been given another name"
-      :erlang.error ArgumentError.exception(message), [pid_or_port, name]
+  def register(name, pid) do
+    :erlang.register(name, pid)
  end

-  defp pid_or_port(pid) when is_pid(pid), do: "pid #{inspect pid}"
-  defp pid_or_port(port) when is_port(port), do: "port #{inspect port}"
-
  @doc """
-  Removes the registered `name`, associated with a PID
-  or a port identifier.
+  Removes the registered name, associated with a pid or a port identifier.

-  Fails with `ArgumentError` if the name is not registered
-  to any PID or port.
+  See http://www.erlang.org/doc/man/erlang.html#unregister-1 for more info.
  """
-  @spec unregister(atom) :: true
  def unregister(name) do
    :erlang.unregister(name)
  end

  @doc """
-  Returns the PID or port identifier with the registered `name`.
-  Returns `nil` if the name is not registered.
+  Returns the pid or port identifier with the registered name.
+  Returns undefined if the name is not registered.

-  See [`:erlang.whereis/1`](http://www.erlang.org/doc/man/erlang.html#whereis-1) for more info.
+  See http://www.erlang.org/doc/man/erlang.html#whereis-1 for more info.
  """
-  @spec whereis(atom) :: pid | port | nil
  def whereis(name) do
-    nillify :erlang.whereis(name)
+    :erlang.whereis(name)
  end

  @doc """
-  Returns the PID of the group leader for the process which evaluates the function.
+  Returns a list of names which have been registered using register/2.
  """
-  @spec group_leader :: pid
-  def group_leader do
-    :erlang.group_leader
-  end
-
-  @doc """
-  Sets the group leader of `pid` to `leader`. Typically, this is used when a processes
-  started from a certain shell should have a group leader other than `:init`.
-  """
-  @spec group_leader(pid, leader :: pid) :: true
-  def group_leader(pid, leader) do
-    :erlang.group_leader(leader, pid)
-  end
-
-  @doc """
-  Returns a list of names which have been registered using `register/2`.
-  """
-  @spec registered :: [atom]
  def registered do
    :erlang.registered()
  end

-  @typep process_flag :: :trap_exit | :error_handler | :min_heap_size |
-                         :min_bin_vheap_size | :priority | :save_calls |
-                         :sensitive
  @doc """
  Sets certain flags for the process which calls this function.
-  Returns the old value of the `flag`.
+  Returns the old value of the flag.

-  See [`:erlang.process_flag/2`](http://www.erlang.org/doc/man/erlang.html#process_flag-2) for more info.
+  See http://www.erlang.org/doc/man/erlang.html#process_flag-2 for more info.
  """
-  @spec flag(process_flag, term) :: term
  def flag(flag, value) do
    :erlang.process_flag(flag, value)
  end

  @doc """
-  Sets certain flags for the process `pid`, in the same manner as `flag/2`.
-  Returns the old value of the `flag`. The allowed values for `flag` are
-  only a subset of those allowed in `flag/2`, namely `:save_calls`.
+  Sets certain flags for the process Pid, in the same manner as flag/2.
+  Returns the old value of the flag. The allowed values for Flag are
+  only a subset of those allowed in flag/2, namely: save_calls.

-  See [`:erlang.process_flag/3`](http://www.erlang.org/doc/man/erlang.html#process_flag-3) for more info.
+  See http://www.erlang.org/doc/man/erlang.html#process_flag-3 for more info.
  """
-  @spec flag(pid, :save_calls, non_neg_integer) :: non_neg_integer
  def flag(pid, flag, value) do
    :erlang.process_flag(pid, flag, value)
  end

  @doc """
-  Returns information about the process identified by `pid`, or returns `nil` if the process
-  is not alive.
-  Use this only for debugging information.
+  Returns information about the process identified by pid
+  or undefined if the process is not alive.

-  See [`:erlang.process_info/1`](http://www.erlang.org/doc/man/erlang.html#process_info-1) for more info.
+  See http://www.erlang.org/doc/man/erlang.html#process_info-2 for more info.
  """
-  @spec info(pid) :: Keyword.t
-  def info(pid) do
-    nillify :erlang.process_info(pid)
+  def info(pid, spec) do
+    :erlang.process_info(pid, spec)
  end

-  @doc """
-  Returns information about the process identified by `pid`,
-  or returns `nil` if the process is not alive.
-
-  See [`:erlang.process_info/2`](http://www.erlang.org/doc/man/erlang.html#process_info-2) for more info.
-  """
-  @spec info(pid, atom | [atom]) :: {atom, term} | [{atom, term}]  | nil
-  def info(pid, spec)
-
-  def info(pid, :registered_name) do
-    case :erlang.process_info(pid, :registered_name) do
-      :undefined -> nil
-      [] -> {:registered_name, []}
-      other -> other
-    end
-  end
-
-  def info(pid, spec) when is_atom(spec) or is_list(spec) do
-    nillify :erlang.process_info(pid, spec)
-  end
-
-  @doc """
-  Puts the calling process into a wait state
-  where its memory allocation has been reduced as much as possible,
-  which is useful if the process does not expect to receive any messages
-  in the near future.
-
-  See [`:erlang.hibernate/3`](http://www.erlang.org/doc/man/erlang.html#hibernate-3) for more info.
-
-  Inlined by the compiler.
-  """
-  @spec hibernate(module, atom, list) :: no_return
-  def hibernate(mod, fun, args) do
-    :erlang.hibernate(mod, fun, args)
-  end
-
-  @compile {:inline, nillify: 1}
  defp nillify(:undefined), do: nil
  defp nillify(other),      do: other
 end
@@ -1,662 +1,308 @@
 defmodule Protocol do
-  @moduledoc """
-  Functions for working with protocols.
-  """
+  @moduledoc false
+
+  # We need to use Erlang.lists because Enum is not available yet
+  require Erlang.lists, as: L

  @doc """
-  Defines a new protocol function.
+  Handle `defprotocol`. It will define a function for each
+  protocol plus two extra functions:

-  Protocols do not allow functions to be defined directly, instead, the
-  regular `Kernel.def/*` macros are replaced by this macro which
-  defines the protocol functions with the appropriate callbacks.
+  * `__protocol__/1` - returns the protocol name when :name is given,
+                       and a keywords list with the protocol functions
+                       when :functions is given;
+
+  * `__impl_for__/1` - receives one argument and returns a module
+                       that implements the protocol for the given
+                       data type. If no implementation matches, returns nil;
+
+  * `__impl_for__!/1` - same as above but raises an error if an implementation is not found
  """
-  defmacro def(signature)
-
-  defmacro def({_, _, args}) when args == [] or is_atom(args) do
-    raise ArgumentError, "protocol functions expect at least one argument"
-  end
-
-  defmacro def({name, _, args}) when is_atom(name) and is_list(args) do
-    arity = length(args)
-
-    type_args = :lists.map(fn _ -> quote(do: term) end,
-                           :lists.seq(2, arity))
-    type_args = [quote(do: t) | type_args]
-
-    call_args = :lists.map(fn i -> {String.to_atom(<<?x, i + 64>>), [], __MODULE__} end,
-                           :lists.seq(2, arity))
-    call_args = [quote(do: t) | call_args]
-
-    quote do
-      name  = unquote(name)
-      arity = unquote(arity)
-
-      @functions [{name, arity} | @functions]
-
-      # Generate a fake definition with the user
-      # signature that will be used by docs
-      Kernel.def unquote(name)(unquote_splicing(args))
-
-      # Generate the actual implementation
-      Kernel.def unquote(name)(unquote_splicing(call_args)) do
-        impl_for!(t).unquote(name)(unquote_splicing(call_args))
-      end
-
-      # Convert the spec to callback if possible,
-      # otherwise generate a dummy callback
-      Protocol.__spec__?(__MODULE__, name, arity) ||
-        @callback unquote(name)(unquote_splicing(type_args)) :: term
-    end
-  end
-
-  defmacro def(_) do
-    raise ArgumentError, "invalid args for def inside defprotocol"
-  end
-
-  @doc """
-  Checks if the given module is loaded and is protocol.
-
-  Returns `:ok` if so, otherwise raises `ArgumentError`.
-  """
-  @spec assert_protocol!(module) :: :ok | no_return
-  def assert_protocol!(module) do
-    assert_protocol!(module, "")
-  end
-
-  defp assert_protocol!(module, extra) do
-    case Code.ensure_compiled(module) do
-      {:module, ^module} -> :ok
-      _ -> raise ArgumentError, "#{inspect module} is not available" <> extra
-    end
-
-    try do
-      module.__protocol__(:module)
-    rescue
-      UndefinedFunctionError ->
-        raise ArgumentError, "#{inspect module} is not a protocol" <> extra
-    end
-
-    :ok
-  end
-
-  @doc """
-  Checks if the given module is loaded and is an implementation
-  of the given protocol.
-
-  Returns `:ok` if so, otherwise raises `ArgumentError`.
-  """
-  @spec assert_impl!(module, module) :: :ok | no_return
-  def assert_impl!(protocol, base) do
-    assert_impl!(protocol, base, "")
-  end
-
-  defp assert_impl!(protocol, base, extra) do
-    impl = Module.concat(protocol, base)
-
-    case Code.ensure_compiled(impl) do
-      {:module, ^impl} -> :ok
-      _ -> raise ArgumentError,
-             "#{inspect impl} is not available" <> extra
-    end
-
-    try do
-      impl.__impl__(:protocol)
-    rescue
-      UndefinedFunctionError ->
-        raise ArgumentError,
-          "#{inspect impl} is not an implementation of a protocol" <> extra
-    else
-      ^protocol ->
-        :ok
-      other ->
-        raise ArgumentError,
-          "expected #{inspect impl} to be an implementation of #{inspect protocol}, got: #{inspect other}" <> extra
-    end
-  end
-
-  @doc """
-  Derives the `protocol` for `module` with the given options.
-  """
-  defmacro derive(protocol, module, options \\ []) do
-    quote do
-      module = unquote(module)
-      Protocol.__derive__([{unquote(protocol), unquote(options)}], module, __ENV__)
-    end
-  end
-
-  ## Consolidation
-
-  @doc """
-  Extracts all protocols from the given paths.
-
-  The paths can be either a charlist or a string. Internally
-  they are worked on as charlists, so passing them as lists
-  avoid extra conversion.
-
-  Does not load any of the protocols.
-
-  ## Examples
-
-      # Get Elixir's ebin and retrieve all protocols
-      iex> path = :code.lib_dir(:elixir, :ebin)
-      iex> mods = Protocol.extract_protocols([path])
-      iex> Enumerable in mods
-      true
-
-  """
-  @spec extract_protocols([charlist | String.t]) :: [atom]
-  def extract_protocols(paths) do
-    extract_matching_by_attribute paths, 'Elixir.',
-      fn module, attributes ->
-        case attributes[:protocol] do
-          [fallback_to_any: _] -> module
-          _ -> nil
-        end
-      end
-  end
-
-  @doc """
-  Extracts all types implemented for the given protocol from
-  the given paths.
-
-  The paths can be either a charlist or a string. Internally
-  they are worked on as charlists, so passing them as lists
-  avoid extra conversion.
-
-  Does not load any of the implementations.
-
-  ## Examples
-
-      # Get Elixir's ebin and retrieve all protocols
-      iex> path = :code.lib_dir(:elixir, :ebin)
-      iex> mods = Protocol.extract_impls(Enumerable, [path])
-      iex> List in mods
-      true
-
-  """
-  @spec extract_impls(module, [charlist | String.t]) :: [atom]
-  def extract_impls(protocol, paths) when is_atom(protocol) do
-    prefix = Atom.to_charlist(protocol) ++ '.'
-    extract_matching_by_attribute paths, prefix, fn
-      _mod, attributes ->
-        case attributes[:impl] do
-          [protocol: ^protocol, for: for] -> for
-          _ -> nil
-        end
-    end
-  end
-
-  defp extract_matching_by_attribute(paths, prefix, callback) do
-    for path <- paths,
-       file <- list_dir(path),
-       mod = extract_from_file(path, file, prefix, callback),
-       do: mod
-  end
-
-  defp list_dir(path) when is_list(path) do
-    case :file.list_dir(path) do
-      {:ok, files} -> files
-      _ -> []
-    end
-  end
-
-  defp list_dir(path), do: list_dir(to_charlist(path))
-
-  defp extract_from_file(path, file, prefix, callback) do
-    if :lists.prefix(prefix, file) and :filename.extension(file) == '.beam' do
-      extract_from_beam(:filename.join(path, file), callback)
-    end
-  end
-
-  defp extract_from_beam(file, callback) do
-    case :beam_lib.chunks(file, [:attributes]) do
-      {:ok, {module, [attributes: attributes]}} ->
-        callback.(module, attributes)
-       _ ->
-         nil
-    end
-  end
-
-  @doc """
-  Returns `true` if the protocol was consolidated.
-  """
-  @spec consolidated?(module) :: boolean
-  def consolidated?(protocol) do
-    protocol.__protocol__(:consolidated?)
-  end
-
-  @doc """
-  Receives a protocol and a list of implementations and
-  consolidates the given protocol.
-
-  Consolidation happens by changing the protocol `impl_for`
-  in the abstract format to have fast lookup rules. Usually
-  the list of implementations to use during consolidation
-  are retrieved with the help of `extract_impls/2`.
-
-  It returns the updated version of the protocol bytecode.
-  A given bytecode or protocol implementation can be checked
-  to be consolidated or not by analyzing the protocol
-  attribute:
-
-      Protocol.consolidated?(Enumerable)
-
-  If the first element of the tuple is `true`, it means
-  the protocol was consolidated.
-
-  This function does not load the protocol at any point
-  nor loads the new bytecode for the compiled module.
-  However each implementation must be available and
-  it will be loaded.
-  """
-  @spec consolidate(module, [module]) ::
-    {:ok, binary} |
-    {:error, :not_a_protocol} |
-    {:error, :no_beam_info}
-  def consolidate(protocol, types) when is_atom(protocol) do
-    with {:ok, info} <- beam_protocol(protocol),
-         {:ok, code, docs} <- change_debug_info(info, types),
-         do: compile(code, docs)
-  end
-
-  @docs_chunk 'ExDc'
-
-  defp beam_protocol(protocol) do
-    chunk_ids = [:abstract_code, :attributes, @docs_chunk]
-    opts = [:allow_missing_chunks]
-    case :beam_lib.chunks(beam_file(protocol), chunk_ids, opts) do
-      {:ok, {^protocol, [{:abstract_code, {_raw, abstract_code}},
-                         {:attributes, attributes},
-                         {@docs_chunk, docs}]}} ->
-        case attributes[:protocol] do
-          [fallback_to_any: any] ->
-            {:ok, {protocol, any, abstract_code, docs}}
-          _ ->
-            {:error, :not_a_protocol}
-        end
-      _ ->
-        {:error, :no_beam_info}
-    end
-  end
-
-  defp beam_file(module) when is_atom(module) do
-    case :code.which(module) do
-      atom when is_atom(atom) -> module
-      file -> file
-    end
-  end
-
-  # Change the debug information to the optimized
-  # impl_for/1 dispatch version.
-  defp change_debug_info({protocol, any, code, docs}, types) do
-    types   = if any, do: types, else: List.delete(types, Any)
-    all     = [Any] ++ for {_guard, mod} <- __builtin__(), do: mod
-    structs = types -- all
-    case change_impl_for(code, protocol, types, structs, false, []) do
-      {:ok, ret} -> {:ok, ret, docs}
-      other      -> other
-    end
-  end
-
-  defp change_impl_for([{:function, line, :__protocol__, 1, clauses} | t], protocol, types, structs, _, acc) do
-    clauses = :lists.map(fn
-      {:clause, l, [{:atom, _, :consolidated?}], [], [{:atom, _, _}]} ->
-        {:clause, l, [{:atom, 0, :consolidated?}], [], [{:atom, 0, true}]}
-      {:clause, _, _, _, _} = c ->
-        c
-    end, clauses)
-
-    change_impl_for(t, protocol, types, structs, true,
-                    [{:function, line, :__protocol__, 1, clauses} | acc])
-  end
-
-  defp change_impl_for([{:function, line, :impl_for, 1, _} | t], protocol, types, structs, is_protocol, acc) do
-    fallback = if Any in types, do: load_impl(protocol, Any)
-
-    clauses = for {guard, mod} <- __builtin__(),
-                  mod in types,
-                  do: builtin_clause_for(mod, guard, protocol, line)
-
-    clauses = [struct_clause_for(line) | clauses] ++
-              [fallback_clause_for(fallback, protocol, line)]
-
-    change_impl_for(t, protocol, types, structs, is_protocol,
-                    [{:function, line, :impl_for, 1, clauses} | acc])
-  end
-
-  defp change_impl_for([{:function, line, :struct_impl_for, 1, _} | t], protocol, types, structs, is_protocol, acc) do
-    fallback = if Any in types, do: load_impl(protocol, Any)
-    clauses = for struct <- structs, do: each_struct_clause_for(struct, protocol, line)
-    clauses = clauses ++ [fallback_clause_for(fallback, protocol, line)]
-
-    change_impl_for(t, protocol, types, structs, is_protocol,
-                    [{:function, line, :struct_impl_for, 1, clauses} | acc])
-  end
-
-  defp change_impl_for([h | t], protocol, info, types, is_protocol, acc) do
-    change_impl_for(t, protocol, info, types, is_protocol, [h | acc])
-  end
-
-  defp change_impl_for([], protocol, _info, _types, is_protocol, acc) do
-    if is_protocol do
-      {:ok, {protocol, Enum.reverse(acc)}}
-    else
-      {:error, :not_a_protocol}
-    end
-  end
-
-  defp builtin_clause_for(mod, guard, protocol, line) do
-    {:clause, line,
-      [{:var, line, :x}],
-      [[{:call, line,
-          {:remote, line, {:atom, line, :erlang}, {:atom, line, guard}},
-          [{:var, line, :x}],
-     }]],
-      [{:atom, line, load_impl(protocol, mod)}]}
-  end
-
-  defp struct_clause_for(line) do
-    {:clause, line,
-      [{:map, line, [
-        {:map_field_exact, line, {:atom, line, :__struct__}, {:var, line, :x}}
-      ]}],
-      [[{:call, line,
-          {:remote, line, {:atom, line, :erlang}, {:atom, line, :is_atom}},
-          [{:var, line, :x}],
-     }]],
-      [{:call, line,
-          {:atom, line, :struct_impl_for},
-          [{:var, line, :x}]}]}
-  end
-
-  defp each_struct_clause_for(other, protocol, line) do
-    {:clause, line, [{:atom, line, other}], [],
-      [{:atom, line, load_impl(protocol, other)}]}
-  end
-
-  defp fallback_clause_for(value, _protocol, line) do
-    {:clause, line, [{:var, line, :_}], [],
-      [{:atom, line, value}]}
-  end
-
-  defp load_impl(protocol, for) do
-    Module.concat(protocol, for).__impl__(:target)
-  end
-
-  # Finally compile the module and emit its bytecode.
-  defp compile({protocol, code}, docs) do
-    opts = if Code.compiler_options[:debug_info], do: [:debug_info], else: []
-    {:ok, ^protocol, binary, _warnings} = :compile.forms(code, [:return | opts])
-    {:ok,
-      case docs do
-        :missing_chunk -> binary
-        _ -> :elixir_module.add_beam_chunk(binary, @docs_chunk, docs)
-      end}
-  end
-
-  ## Definition callbacks
-
-  @doc false
-  def __protocol__(name, [do: block]) do
+  def defprotocol(name, [do: block]) do
    quote do
      defmodule unquote(name) do
-        # We don't allow function definition inside protocols
+        # Remove "harmful" macros
+        # We don't want to allow function definition inside protocols
        import Kernel, except: [
-          defmacrop: 1, defmacrop: 2, defmacro: 1, defmacro: 2,
-          defp: 1, defp: 2, def: 1, def: 2
+          defmacro: 1, defmacro: 2, defmacro: 4,
+          defp: 1, defp: 2, defp: 4,
+          def: 1, def: 2, def: 4
        ]

        # Import the new dsl that holds the new def
-        import Protocol, only: [def: 1]
-
-        # Compile with debug info for consolidation
-        @compile :debug_info
+        import Protocol.DSL

        # Set up a clear slate to store defined functions
        @functions []
-        @fallback_to_any false

        # Invoke the user given block
-        _ = unquote(block)
+        unquote(block)

-        # Finalize expansion
-        unquote(after_defprotocol())
+        # Define callbacks and meta information
+        { conversions, fallback } = Protocol.conversions_for(__MODULE__, @only, @except)
+        Protocol.impl_for(__ENV__, conversions)
+        Protocol.meta(__ENV__, @functions, fallback)
      end
    end
  end

-  defp after_defprotocol do
-    quote bind_quoted: [builtin: __builtin__()] do
-      @doc false
-      @spec impl_for(term) :: atom | nil
-      Kernel.def impl_for(data)
-
-      # Define the implementation for structs.
-      #
-      # It simply delegates to struct_impl_for which is then
-      # optimized during protocol consolidation.
-      Kernel.def impl_for(%{__struct__: struct}) when :erlang.is_atom(struct) do
-        struct_impl_for(struct)
-      end
-
-      # Define the implementation for built-ins
-      :lists.foreach(fn {guard, mod} ->
-        target = Module.concat(__MODULE__, mod)
-
-        Kernel.def impl_for(data) when :erlang.unquote(guard)(data) do
-          case impl_for?(unquote(target)) do
-            true  -> unquote(target).__impl__(:target)
-            false -> any_impl_for()
-          end
-        end
-      end, builtin)
-
-      # Define a catch-all impl_for/1 clause to pacify Dialyzer (since
-      # destructuring opaque types is illegal, Dialyzer will think none of the
-      # previous clauses matches opaque types, and without this clause, will
-      # conclude that impl_for can't handle an opaque argument). This is a hack
-      # since it relies on Dialyzer not being smart enough to conclude that all
-      # opaque types will get the any_impl_for/0 implementation.
-      Kernel.def impl_for(_) do
-        any_impl_for()
-      end
-
-      @doc false
-      @spec impl_for!(term) :: atom | no_return
-      Kernel.def impl_for!(data) do
-        impl_for(data) || raise(Protocol.UndefinedError, protocol: __MODULE__, value: data)
-      end
-
-      # Internal handler for Any
-      if @fallback_to_any do
-        Kernel.defp any_impl_for(), do: __MODULE__.Any.__impl__(:target)
-      else
-        Kernel.defp any_impl_for(), do: nil
-      end
-
-      # Internal handler for Structs
-      Kernel.defp struct_impl_for(struct) do
-        target = Module.concat(__MODULE__, struct)
-        case impl_for?(target) do
-          true  -> target.__impl__(:target)
-          false -> any_impl_for()
-        end
-      end
-
-      # Check if compilation is available internally
-      Kernel.defp impl_for?(target) do
-        Code.ensure_compiled?(target) and
-          function_exported?(target, :__impl__, 1)
-      end
-
-      # Inline any and struct implementations
-      @compile {:inline, any_impl_for: 0, struct_impl_for: 1, impl_for?: 1}
-
-      unless Kernel.Typespec.defines_type?(__MODULE__, :t, 0) do
-        @type t :: term
-      end
-
-      # Store information as an attribute so it
-      # can be read without loading the module.
-      Module.register_attribute(__MODULE__, :protocol, persist: true)
-      @protocol [fallback_to_any: !!@fallback_to_any]
-
-      @doc false
-      @spec __protocol__(:module) :: __MODULE__
-      @spec __protocol__(:functions) :: unquote(Protocol.__functions_spec__(@functions))
-      @spec __protocol__(:consolidated?) :: boolean
-      Kernel.def __protocol__(:module), do: __MODULE__
-      Kernel.def __protocol__(:functions), do: unquote(:lists.sort(@functions))
-      Kernel.def __protocol__(:consolidated?), do: false
-    end
-  end
-
-  @doc false
-  def __functions_spec__([]),
-    do: []
-  def __functions_spec__([h | t]),
-    do: [:lists.foldl(&{:|, [], [&1, &2]}, h, t), quote(do: ...)]
-
-  @doc false
-  def __impl__(protocol, opts) do
-    do_defimpl(protocol, :lists.keysort(1, opts))
-  end
-
-  defp do_defimpl(protocol, [do: block, for: for]) when is_list(for) do
-    for f <- for, do: do_defimpl(protocol, [do: block, for: f])
-  end
-
-  defp do_defimpl(protocol, [do: block, for: for]) do
-    # Unquote the implementation just later
-    # when all variables will already be injected
-    # into the module body.
-    impl =
-      quote unquote: false do
-        @doc false
-        @spec __impl__(:for) :: unquote(for)
-        @spec __impl__(:target) :: __MODULE__
-        @spec __impl__(:protocol) :: unquote(protocol)
-        def __impl__(:for),      do: unquote(for)
-        def __impl__(:target),   do: __MODULE__
-        def __impl__(:protocol), do: unquote(protocol)
-      end
-
+  @doc """
+  Implement the given protocol for the given module.
+  It also defines a `__impl__` function which
+  returns the protocol being implemented.
+  """
+  def defimpl(protocol, [do: block, for: for]) do
    quote do
      protocol = unquote(protocol)
      for      = unquote(for)
      name     = Module.concat(protocol, for)

-      Protocol.assert_protocol!(protocol)
-      Protocol.__ensure_defimpl__(protocol, for, __ENV__)
+      Protocol.assert_protocol(protocol)

      defmodule name do
-        @behaviour protocol
-        @protocol  protocol
-        @for       for
-
+        def __impl__, do: unquote(protocol)
        unquote(block)
-
-        Module.register_attribute(__MODULE__, :impl, persist: true)
-        @impl [protocol: @protocol, for: @for]
-
-        unquote(impl)
      end
+
+      Protocol.assert_impl(name, protocol)
    end
  end

-  @doc false
-  def __derive__(derives, for, %Macro.Env{} = env) when is_atom(for) do
-    struct =
-      if for == env.module do
-        Module.get_attribute(for, :struct) ||
-          raise "struct is not defined for #{inspect for}"
-      else
-        for.__struct__
-      end
+  @doc """
+  Check if the given module is a protocol. Raises an error
+  if not loaded or not a protocol.
+  """
+  def assert_protocol(module) do
+    case :code.ensure_loaded(module) do
+      { :module, ^module } -> nil
+      _ -> raise ArgumentError, message: "#{module} is not loaded"
+    end

-    :lists.foreach(fn
-      proto when is_atom(proto) ->
-        derive(proto, for, struct, [], env)
-      {proto, opts} when is_atom(proto) ->
-        derive(proto, for, struct, opts, env)
-    end, :lists.flatten(derives))
-
-    :ok
+    try do
+      module.__protocol__(:name)
+    rescue
+      UndefinedFunctionError ->
+        raise ArgumentError, message: "#{module} is not a protocol"
+    end
  end

-  defp derive(protocol, for, struct, opts, env) do
-    extra = ", cannot derive #{inspect protocol} for #{inspect for}"
-    assert_protocol!(protocol, extra)
-    __ensure_defimpl__(protocol, for, env)
-    assert_impl!(protocol, Any, extra)
+  @doc """
+  Check if the given `impl` is a valid impl for `protocol`.
+  Raises an error if not.

-    # Clean up variables from eval context
-    env  = %{env | vars: [], export_vars: nil}
-    args = [for, struct, opts]
-    impl = Module.concat(protocol, Any)
+  """
+  def assert_impl(impl, protocol) do
+    remaining = protocol.__protocol__(:functions) -- impl.__info__(:functions)

-    :elixir_module.expand_callback(env.line, impl, :__deriving__, args, env, fn
-      mod, fun, args ->
-        if function_exported?(mod, fun, length(args)) do
-          apply(mod, fun, args)
+    if remaining != [] do
+      pp = Enum.map_join remaining, ", ", fn {x,y} -> "#{x}/#{y}" end
+      raise ArgumentError,
+        message: "#{inspect impl} did not implement #{inspect protocol}, missing: #{pp}"
+    end
+  end
+
+  @doc """
+  Defines meta information about the protocol and internal callbacks.
+  """
+  def meta(env, functions, fallback) do
+    contents = quote do
+      def __protocol__(:name),      do: __MODULE__
+      def __protocol__(:functions), do: unquote(:lists.sort(functions))
+
+      def __impl_for__(arg) do
+        case __raw_impl__(arg) do
+          __MODULE__.Record ->
+            target = Module.concat(__MODULE__, :erlang.element(1, arg))
+            try do
+              target.__impl__
+              target
+            rescue
+              UndefinedFunctionError -> __fallback__
+            end
+          other ->
+            other
+        end
+      end
+
+      def __impl_for__!(arg) do
+        if module = __impl_for__(arg) do
+          module
        else
-          Module.create(Module.concat(protocol, for), quote do
-            Module.register_attribute(__MODULE__, :impl, persist: true)
-            @impl [protocol: unquote(protocol), for: unquote(for)]
-
-            @doc false
-            @spec __impl__(:target) :: unquote(impl)
-            @spec __impl__(:protocol) :: unquote(protocol)
-            @spec __impl__(:for) :: unquote(for)
-            def __impl__(:target),   do: unquote(impl)
-            def __impl__(:protocol), do: unquote(protocol)
-            def __impl__(:for),      do: unquote(for)
-          end, Macro.Env.location(env))
+          raise Protocol.UndefinedError, protocol: __MODULE__, structure: arg
        end
-    end)
-  end
+      end

-  @doc false
-  def __ensure_defimpl__(protocol, for, env) do
-    if Protocol.consolidated?(protocol) do
-      message =
-        "the #{inspect protocol} protocol has already been consolidated" <>
-        ", an implementation for #{inspect for} has no effect"
-      :elixir_errors.warn(env.line, env.file, message)
+      defp __fallback__, do: unquote(fallback)
    end
-    :ok
+
+    Module.eval_quoted env, contents
  end

-  @doc false
-  def __spec__?(module, name, arity) do
-    signature = {name, arity}
+  @doc """
+  Implements the function that detects the protocol and returns
+  the module to dispatch to. Returns module.Record for records
+  which should be properly handled by the dispatching function.
+  """
+  def impl_for(env, conversions) do
+    contents = lc kind inlist conversions, do: each_impl_for(kind, conversions)

-    specs = Module.get_attribute(module, :spec)
-    found =
-      :lists.map(fn {:spec, expr, caller} ->
-        if Kernel.Typespec.spec_to_signature(expr) == signature do
-          Kernel.Typespec.define_spec(:callback, expr, caller)
-          true
+    # If we don't implement all protocols and any is not in the
+    # list, we need to add a final clause that returns nil.
+    if !L.member({ Any, :is_any }, conversions) && length(conversions) < 10 do
+      contents = contents ++ [quote do
+        defp __raw_impl__(_) do
+          nil
        end
-      end, specs)
+      end]
+    end

-    :lists.any(& &1 == true, found)
+    Module.eval_quoted env, contents
+  end
+
+  @doc """
+  Returns the default conversions according to the given
+  only/except options.
+  """
+  def conversions_for(module, only, except) do
+    kinds = all_types
+
+    conversions =
+      if only do
+        L.map(fn i -> L.keyfind(i, 1, kinds) end, only)
+      else
+        except = except || [Any]
+        L.foldl(fn i, list -> L.keydelete(i, 1, list) end, kinds, except)
+      end
+
+    fallback = cond do
+      L.keyfind(Tuple, 1, conversions) ->
+        Module.concat module, Tuple
+      L.keyfind(Any, 1, conversions) ->
+        Module.concat module, Any
+      true ->
+        nil
+    end
+
+    { conversions, fallback }
  end

  ## Helpers

-  @doc false
-  def __builtin__ do
-    [is_tuple: Tuple,
-     is_atom: Atom,
-     is_list: List,
-     is_map: Map,
-     is_bitstring: BitString,
-     is_integer: Integer,
-     is_float: Float,
-     is_function: Function,
-     is_pid: PID,
-     is_port: Port,
-     is_reference: Reference]
+  defp all_types do
+    [
+      { Record,    :is_record },
+      { Tuple,     :is_tuple },
+      { Atom,      :is_atom },
+      { List,      :is_list },
+      { BitString, :is_bitstring },
+      { Number,    :is_number },
+      { Function,  :is_function },
+      { PID,       :is_pid },
+      { Port,      :is_port },
+      { Reference, :is_reference },
+      { Any,       :is_any }
+    ]
+  end
+
+  # Returns a quoted expression that allow to checks
+  # if a variable named first is built in or not.
+  defp is_builtin?([{h,_}]) do
+    quote do
+      first == unquote(h)
+    end
+  end
+
+  defp is_builtin?([{h,_}|t]) do
+    quote do
+      first == unquote(h) or unquote(is_builtin?(t))
+    end
+  end
+
+  # Specially handle tuples as they can also be record.
+  # If this is the case, module.Record will be returned.
+  defp each_impl_for({ _, :is_record }, conversions) do
+    quote do
+      defp __raw_impl__(arg) when is_tuple(arg) and is_atom(:erlang.element(1, arg)) do
+        first = :erlang.element(1, arg)
+        case unquote(is_builtin?(conversions)) do
+          true  -> __MODULE__.Tuple
+          false ->
+            case atom_to_list(first) do
+              'Elixir-' ++ _ -> __MODULE__.Record
+              _ -> __MODULE__.Tuple
+            end
+        end
+      end
+    end
+  end
+
+  # Special case any as we don't need to generate a guard.
+  defp each_impl_for({ _, :is_any }, _) do
+    quote do
+      defp __raw_impl__(_) do
+        __MODULE__.Any
+      end
+    end
+  end
+
+  # Generate all others protocols.
+  defp each_impl_for({ kind, fun }, _) do
+    quote do
+      defp __raw_impl__(arg) when unquote(fun).(arg) do
+        Module.concat __MODULE__, unquote(kind)
+      end
+    end
  end
 end
+
+defmodule Protocol.DSL do
+  @moduledoc false
+
+  defmacro def(expression) do
+    { name, arity } =
+      case expression do
+        { _, _, args } when args == [] or is_atom(args) ->
+          raise ArgumentError, message: "protocol functions expect at least one argument"
+        { name, _, args } when is_atom(name) and is_list(args) ->
+          { name, length(args) }
+        _ ->
+          raise ArgumentError, message: "invalid args for defprotocol"
+      end
+
+    # Generate arguments according the arity. The arguments
+    # are named xa, xb and so forth. We cannot use string
+    # interpolation to generate the arguments because of compile
+    # dependencies, so we use the <<>> instead.
+    args = lc i inlist :lists.seq(1, arity) do
+      { binary_to_atom(<<?x, i + 64>>), 0, :quoted }
+    end
+
+    quote do
+      # Append new function to the list
+      @functions [unquote({name, arity})|@functions]
+
+      Kernel.def unquote(name).(unquote_splicing(args)) do
+        args = [unquote_splicing(args)]
+        case __raw_impl__(xA) do
+          __MODULE__.Record ->
+            try do
+              target = Module.concat(__MODULE__, :erlang.element(1, xA))
+              apply target, unquote(name), args
+            rescue
+              UndefinedFunctionError ->
+                case __fallback__ do
+                  nil ->
+                    raise Protocol.UndefinedError, protocol: __MODULE__, structure: xA
+                  other ->
+                    apply other, unquote(name), args
+                end
+            end
+          nil ->
+            raise Protocol.UndefinedError, protocol: __MODULE__, structure: xA
+          other ->
+            apply other, unquote(name), args
+        end
+      end
+    end
+  end
+end
@@ -1,130 +1,84 @@
 defmodule Range do
-  @moduledoc """
-  Defines a range.
-
-  A range represents a discrete number of values where
-  the first and last values are integers.
-
-  Ranges can be either increasing (first <= last) or
-  decreasing (first > last). Ranges are also always
-  inclusive.
-
-  A Range is represented internally as a struct. However,
-  the most common form of creating and matching on ranges
-  is via the `../2` macro, auto-imported from `Kernel`:
-
-      iex> range = 1..3
-      1..3
-      iex> first..last = range
-      iex> first
-      1
-      iex> last
-      3
-
-  A Range implements the Enumerable protocol, which means
-  all of the functions in the Enum module is available:
-
-      iex> range = 1..10
-      1..10
-      iex> Enum.reduce(range, 0, fn i, acc -> i * i + acc end)
-      385
-      iex> Enum.count(range)
-      10
-      iex> Enum.member?(range, 11)
-      false
-      iex> Enum.member?(range, 8)
-      true
-
-  """
-
-  defstruct first: nil, last: nil
-
-  @type t :: %Range{first: integer, last: integer}
-  @type t(first, last) :: %Range{first: first, last: last}
-
+  def __access__(caller, arg), do: Record.access(caller, __MODULE__, __record__(:fields), arg)
+  def __record__(kind, _),     do: __record__(kind)
+  def __record__(:name),       do: __MODULE__
+  def __record__(:fields),     do: [{:first,nil},{:last,nil}]

  @doc """
-  Creates a new range.
-  """
-  @spec new(integer, integer) :: t
-  def new(first, last) when is_integer(first) and is_integer(last) do
-    %Range{first: first, last: last}
-  end
-
-  def new(first, last) do
-    raise ArgumentError,
-      "ranges (first..last) expect both sides to be integers, " <>
-      "got: #{inspect first}..#{inspect last}"
-  end
-
-  @doc """
-  Returns `true` if the given `term` is a valid range.
+  Returns a new range based on the given options.

  ## Examples

-      iex> Range.range?(1..3)
-      true
-
-      iex> Range.range?(0)
-      false
+      Range.new first: 1, last: 10

  """
-  @spec range?(term) :: boolean
-  def range?(term)
-  def range?(first..last) when is_integer(first) and is_integer(last), do: true
-  def range?(_), do: false
+  def new(options) do
+    {
+      __MODULE__,
+      Keyword.get!(options, :first),
+      Keyword.get!(options, :last)
+    }
+  end
+
+  @doc """
+  Returns the first item of the range.
+  """
+  def first(range) do
+    elem(range, 2)
+  end
+
+  @doc """
+  Returns the last item of the range.
+  """
+  def last(range) do
+    elem(range, 3)
+  end
 end

-defimpl Enumerable, for: Range do
-  def reduce(first..last, acc, fun) do
-    reduce(first, last, acc, fun, last >= first)
+defprotocol Range.Iterator do
+  @doc """
+  How to iterate the range, receives the first
+  and range as arguments. It needs to return a
+  function that receives an item and returns
+  a tuple with two elements: the given item
+  and the next item in the iteration.
+  """
+  def iterator(first, range)
+
+  @doc """
+  Count how many items are in the range.
+  """
+  def count(first, range)
+end
+
+defimpl Enum.Iterator, for: Range do
+  def iterator(Range[first: first] = range) do
+    iterator = Range.Iterator.iterator(first, range)
+    { iterator, iterator.(first) }
  end

-  defp reduce(_x, _y, {:halt, acc}, _fun, _up) do
-    {:halted, acc}
+  def count(Range[first: first] = range) do
+    Range.Iterator.count(first, range)
+  end
+end
+
+defimpl Enum.OrdIterator, for: Range do
+  def iterator(range) do
+    Enum.Iterator.Range.iterator(range)
  end

-  defp reduce(x, y, {:suspend, acc}, fun, up) do
-    {:suspended, acc, &reduce(x, y, &1, fun, up)}
-  end
+  def to_list({ h, next }, iterator), do: [h|to_list(iterator.(next), iterator)]
+  def to_list(:stop, _),              do: []
+end

-  defp reduce(x, y, {:cont, acc}, fun, true) when x <= y do
-    reduce(x + 1, y, fun.(x, acc), fun, true)
-  end
-
-  defp reduce(x, y, {:cont, acc}, fun, false) when x >= y do
-    reduce(x - 1, y, fun.(x, acc), fun, false)
-  end
-
-  defp reduce(_, _, {:cont, acc}, _fun, _up) do
-    {:done, acc}
-  end
-
-  def member?(first..last, value) when is_integer(value) do
-    if first <= last do
-      {:ok, first <= value and value <= last}
-    else
-      {:ok, last <= value and value <= first}
+defimpl Range.Iterator, for: Number do
+  def iterator(first, Range[last: last]) when is_integer(first) and is_integer(last) do
+    fn(current) ->
+      if current > last, do: :stop, else: { current, current + 1 }
    end
  end

-  def member?(_.._, _value) do
-    {:ok, false}
+  def count(first, Range[last: last]) when is_integer(first) and is_integer(last) do
+    last - first + 1
  end
-
-  def count(first..last) do
-    if first <= last do
-      {:ok, last - first + 1}
-    else
-      {:ok, first - last + 1}
-    end
-  end
-end
-
-defimpl Inspect, for: Range do
-  import Inspect.Algebra
-
-  def inspect(first..last, opts) do
-    concat [to_doc(first, opts), "..", to_doc(last, opts)]
-  end
-end
+end
--- a/Show More
+++ b/Show More
				`@@ -1 +0,0 @@`
				`lib/elixir/test/elixir/fixtures/*.txt text eol=lf`