Release v0.11.2

Merge pull request #1876 from alco/before-compile-doc
Fix the example for @before_compile hook
2013-11-14 12:41:45 +01:00 · 2013-11-13 05:33:23 -08:00 · 2013-11-13 15:10:18 +02:00 · 2013-11-12 23:54:26 -08:00 · 2013-11-12 23:26:58 -06:00 · 2013-11-13 00:11:30 +01:00
266 changed files with 11333 additions and 6030 deletions
@@ -1,6 +1,115 @@
+# v0.11.2 (2013-11-14)
+
+* Enhancements
+  * [Mix] Add `mix iex` that redirects users to the proper `iex -S mix` command
+  * [Mix] Support `build_per_environment: true` in project configuration that manages a separete build per environment, useful when you have per-environment behaviour/compilation
+
+* Backwards incompatible changes
+  * [Mix] Mix now compiles files to `_build`. Projects should update just fine, however documentation and books may want to update to the latest information
+
+# v0.11.1 (2013-11-07)
+
+* Enhancements
+  * [Mix] Improve dependency convergence by explicitly checking each requirement instead of expecting all requirements to be equal
+  * [Mix] Support optional dependencies with `optional: true`. Optional dependencies are downloaded for the current project but they are automatically skipped when such project is used as a dependency
+
+* Bug fixes
+  * [Kernel] Set compilation status per ParallelCompiler and not globally
+  * [Mix] Ensure Mix does not load previous dependencies versions before `deps.get`/`deps.update`
+  * [Mix] Ensure umbrella apps are sorted before running recursive commands
+  * [Mix] Ensure umbrella apps run in the same environment as the parent project
+  * [Mix] Ensure dependency tree is topsorted before compiling
+  * [Mix] Raise error when duplicated projects are pushed into the stack
+  * [URI] Allow lowercase escapes in URI
+
+* Backwards incompatible changes
+  * [Mix] Setting `:load_paths` in your project configuration is deprecated
+
+# v0.11.0 (2013-11-02)
+
+* Enhancements
+  * [Code] Eval now returns variables from other contexts
+  * [Dict] Document and enforce all dicts use the match operator (`===`) when checking for keys
+  * [Enum] Add `Enum.slice/2` with a range
+  * [Enum] Document and enforce `Enum.member?/2` to use the match operator (`===`)
+  * [IEx] Split `IEx.Evaluator` from `IEx.Server` to allow custom evaluators
+  * [IEx] Add support for `IEx.pry` which halts a given process for inspection
+  * [IO] Add specs and allow some IO APIs to receive any data that implements `String.Chars`
+  * [Kernel] Improve stacktraces on command line interfaces
+  * [Kernel] Sigils can now handle balanced tokens as in `%s(f(o)o)`
+  * [Kernel] Emit warnings when an alias is not used
+  * [Macro] Add `Macro.pipe/3` and `Macro.unpipe/1` for building pipelines
+  * [Mix] Allow umbrella children to share dependencies between them
+  * [Mix] Allow mix to be escriptize'd
+  * [Mix] Speed mix projects compilation by relying on more manifests information
+  * [Protocol] Protocols now provide `impl_for/1` and `impl_for!/1` functions which receive a structure and returns its respective implementation, otherwise returns nil or an error
+  * [Set] Document and enforce all sets use the match operator (`===`) when checking for keys
+  * [String] Update to Unicode 6.3.0
+  * [String] Add `String.slice/2` with a range
+
+* Bug fixes
+  * [Exception] Ensure `defexception` fields can be set dynamically
+  * [Kernel] Guarantee aliases hygiene is respected when the current module name is not known upfront
+  * [Kernel] `Kernel.access/2` no longer flattens lists
+  * [Mix] Ensure cyclic dependencies are properly handled
+  * [String] Implement the extended grapheme cluster algorithm for `String` operations
+
+* Deprecations
+  * [Kernel] `pid_to_list/1`, `list_to_pid/1`, `binary_to_atom/2`, `binary_to_existing_atom/2` and `atom_to_binary/2` are deprecated in favor of their counterparts in the `:erlang` module
+  * [Kernel] `insert_elem/3` and `delete_elem/2` are deprecated in favor of `Tuple.insert_at/3` and `Tuple.delete_at/2`
+  * [Kernel] Use of `in` inside matches (as in `x in [1,2,3] -> x`) is deprecated in favor of the guard syntax (`x when x in [1,2,3]`)
+  * [Macro] `Macro.expand_all/2` is deprecated
+  * [Protocol] `@only` and `@except` in protocols are now deprecated
+  * [Protocol] Protocols no longer fallback to `Any` out of the box (this functionality needs to be explicitly enabled by setting `@fallback_to_any` to true)
+  * [String] `String.to_integer/1` and `String.to_float/1` are deprecated in favor of `Integer.parse/1` and `Float.parse/1`
+
+* Backwards incompatible changes
+  * [CLI] Reading `.elixirrc` has been dropped in favor of setting env vars
+  * [Kernel] `Kernel.access/2` now expects the second argument to be a compile time list
+  * [Kernel] `fn -> end` quoted expression is no longer wrapped in a `do` keyword
+  * [Kernel] Quoted variables from the same module must be explicitly shared. Previously, if a function returned `quote do: a = 1`, another function from the same module could access it as `quote do: a`. This has been fixed and the variables must be explicitly shared with `var!(a, __MODULE__)`
+  * [Mix] Umbrella apps now treat children apps as dependencies. This means all dependencies will be checked out in the umbrela `deps` directory. On upgrade, child apps need to point to the umbrella project by setting `deps_path: "../../deps_path", lockfile: "../../mix.lock"` in their project config
+  * [Process] `Process.group_leader/2` args have been reversed so the "subject" comes first
+  * [Protocol] Protocol no longer dispatches to `Number`, but to `Integer` and `Float`
+
+# v0.10.3 (2013-10-02)
+
+* Enhancements
+  * [Enum] Add `Enum.take_every/2`
+  * [IEx] IEx now respects signals sent from the Ctrl+G menu
+  * [Kernel] Allow documentation for types with `@typedoc`
+  * [Mix] Allow apps to be selected in umbrella projects
+  * [Record] Generated record functions `new` and `update` also take options with strings as keys
+  * [Stream] Add `Stream.unfold/1`
+
+* Bug fixes
+  * [Dict] Fix a bug when a HashDict was marked as equal when one was actually a subset of the other
+  * [EEx] Solve issue where `do` blocks inside templates were not properly aligned
+  * [ExUnit] Improve checks and have better error reports on poorly aligned doctests
+  * [Kernel] Fix handling of multiple heredocs on the same line
+  * [Kernel] Provide better error messages for match, guard and quoting errors
+  * [Kernel] Make `Kernel.raise/2` a macro to avoid messing up stacktraces
+  * [Kernel] Ensure `&()` works on quoted blocks with only one expression
+  * [Mix] Address an issue where a dependency was not compiled in the proper order when specified in different projects
+  * [Mix] Ensure `compile: false` is a valid mechanism for disabling the compilation of dependencies
+  * [Regex] Fix bug on `Regex.scan/3` when capturing groups and the regex has no groups
+  * [String] Fix a bug with `String.split/2` when given an empty pattern
+  * [Typespec] Guarantee typespecs error reports point to the proper line
+
+* Deprecations
+  * [Kernel] The previous partial application syntax (without the `&` operator) has now been deprecated
+  * [Regex] `Regex.captures/3` is deprecated in favor of `Regex.named_captures/3`
+  * [String] `String.valid_codepoint?/1` is deprecated in favor of pattern matching with `<<_ :: utf8 >>`
+
+* Backwards incompatible changes
+  * [IEx] The `r/0` helper has been removed as it caused surprising behaviour when many modules with dependencies were accumulated
+  * [Mix] `Mix.Version` was renamed to `Version`
+  * [Mix] `File.IteratorError` was renamed to `IO.StreamError`
+  * [Mix] `mix new` now defaults to the `--sup` option, use `--bare` to get the previous behaviour
+
 # v0.10.2 (2013-09-03)

-* enhancements
+* Enhancements
  * [CLI] Add `--verbose` to elixirc, which now is non-verbose by default
  * [Dict] Add `Dict.Behaviour` as a convenience to create your own dictionaries
  * [Enum] Add `Enum.split/2`, `Enum.reduce/2`, `Enum.flat_map/2`, `Enum.chunks/2`, `Enum.chunks/4`, `Enum.chunks_by/2`, `Enum.concat/1` and `Enum.concat/2`
@@ -24,7 +133,7 @@
  * [String] Add `String.ljust/2`, `String.rjust/2`, `String.ljust/3` and `String.rjust/3`
  * [URI] `URI.parse/1` supports IPv6 addresses

-* bug fix
+* Bug fixes
  * [Behaviour] Do not compile behaviour docs if docs are disabled on compilation
  * [ExUnit] Doctests no longer eat too much space and provides detailed reports for poorly indented lines
  * [File] Fix a bug where `File.touch(file, datetime)` was not setting the proper datetime when the file did not exist
@@ -42,7 +151,7 @@
  * [String] `String.slice/3` still returns the proper result when there is no length to be extracted
  * [System] `System.get_env/0` now returns a list of tuples as previously advertised

-* deprecations
+* Deprecations
  * [Dict] `Dict.update/3` is deprecated in favor of `Dict.update!/3`
  * [Enum] `Enum.min/2` and `Enum.max/2` are deprecated in favor of `Enum.min_by/2` and `Enum.max_by/2`
  * [Enum] `Enum.join/2` and `Enum.map_join/3` with a char list are deprecated
@@ -55,7 +164,7 @@
  * [Macro] `Macro.unescape_binary/1` and `Macro.unescape_binary/2` are deprecated in favor of `Macro.unescape_string/1` and `Macro.unescape_string/2`
  * [Mix] `:umbrella` option for umbrella paths has been deprecated in favor of `:in_umbrella`

-* backwards incompatible changes
+* Backwards incompatible changes
  * [IO] IO functions now only accept iolists as arguments
  * [Kernel] `Binary.Chars` was renamed to `String.Chars`
  * [Kernel] The previous ambiguous import syntax `import :functions, Foo` was removed in favor of `import Foo, only: :functions`
@@ -63,7 +172,7 @@

 # v0.10.1 (2013-08-03)

-* enhancements
+* Enhancements
  * [Behaviour] Add support for `defmacrocallback/1`
  * [Enum] Add `Enum.shuffle/1`
  * [ExUnit] The `:trace` option now also reports run time for each test
@@ -86,7 +195,7 @@
  * [String] Add `Regex.scan/3` now supports capturing groups
  * [String] Add `String.reverse/1`

-* bug fix
+* Bug fixes
  * [Behaviour] Ensure callbacks are stored in the definition order
  * [CLI] Speed up boot time on Elixir .bat files
  * [IEx] Reduce cases where IEx parser can get stuck
@@ -101,19 +210,19 @@
  * [OptionParser] Ensure `:keep` and `:integer`|`:float` can be given together as options
  * [OptionParser] Ensure `--no-flag` sets `:flag` to false when `:flag` is a registered boolean switch

-* deprecations
+* Deprecations
  * [Kernel] `function(Mod.fun/arity)` and `function(fun/arity)` are deprecated in favor of `&Mod.fun/arity` and `&fun/arity`
  * [Kernel] `function/3` is deprecated in favor of `Module.function/3`
  * [Kernel] `Kernel.ParallelCompiler` now receives a set of callbacks instead of a single one
  * [Mix] `:test_coverage` option now expect keywords arguments and the `--cover` flag is now treated as a boolean

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Regex] `Regex.scan/3` now always returns a list of lists, normalizing the result, instead of list with mixed lists and binaries
  * [System] `System.halt/2` was removed since the current Erlang implementation of such function is bugged

 # v0.10.0 (2013-07-15)

-* enhancements
+* Enhancements
  * [ExUnit] Support `trace: true` option which gives detailed reporting on test runs
  * [HashDict] Optimize `HashDict` to store pairs in a cons cell reducing storage per key by half
  * [Kernel] Add pretty printing support for inspect
@@ -126,7 +235,7 @@
  * [Mix] Projects can now define an `:elixir` key to outline supported Elixir versions
  * [Typespec] Improve error messages to contain file, line and the typespec itself

-* bug fix
+* Bug fixes
  * [CLI] Elixir can now run on Unix directories with `:` in its path
  * [Kernel] `match?/2` does not leak variables to outer scope
  * [Kernel] Keep `head|tail` format when splicing at the tail
@@ -135,7 +244,7 @@
  * [Mix] Empty projects no longer leave empty ebin files on `mix compile`
  * [Module] Calling `Module.register_attribute/3` no longer automatically changes it to persisted or accumulated

-* deprecations
+* Deprecations
  * [Enum] Receiving the index of iteration in `Enum.map/2` and `Enum.each/2` is deprecated in favor of `Stream.with_index/1`
  * [File] `File.iterator/1` and `File.biniterator/1` are deprecated in favor of `IO.stream/1` and `IO.binstream/1`
  * [File] `File.iterator!/2` and `File.biniterator!/2` are deprecated in favor of `File.stream!/2` and `File.binstream!/2`
@@ -144,7 +253,7 @@
  * [Mix] Deprecate `mix run EXPR` in favor of `mix run -e EXPR`
  * [Record] `Record.__index__/2` deprecated in favor of `Record.__record__(:index, key)`

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Kernel] The `Binary.Inspect` protocol has been renamed to `Inspect`
  * [Kernel] Tighten up the grammar rules regarding parentheses omission, previously the examples below would compile but now they raise an error message:

@@ -157,7 +266,7 @@

 # v0.9.3 (2013-06-23)

-* enhancements
+* Enhancements
  * [File] Add `File.chgrp`, `File.chmod` and `File.chown`
  * [Kernel] Add `--warnings-as-errors` to Elixir's compiler options
  * [Kernel] Print warnings to stderr
@@ -171,7 +280,7 @@
  * [Mix] `github: ...` shortcut now uses the faster `git` schema instead of `https`
  * [Record] Allow types to be given to `defrecordp`

-* bug fix
+* Bug fixes
  * [Kernel] The elixir executable on Windows now supports the same options as the UNIX one
  * [Kernel] Improve error messages on default clauses clash
  * [Kernel] `__MODULE__.Foo` now returns `Foo` when outside of a Module
@@ -180,12 +289,12 @@
  * [Kernel] Allow `(x, y) when z` in function clauses and try expressions
  * [Mix] Mix now properly evaluates rebar scripts

-* deprecations
+* Deprecations
  * [Code] `Code.string_to_ast/1` has been deprecated in favor of `Code.string_to_quoted/1`
  * [Macro] `Macro.to_binary/1` has been deprecated in favor of `Macro.to_string/1`
  * [Typespec] Deprecate `(fun(...) -> ...)` in favor of `(... -> ...)`

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Bitwise] Precedence of operators used by the Bitwise module were changed, check `elixir_parser.yrl` for more information
  * [File] `rm_rf` and `cp_r` now returns a tuple with three elements on failures
  * [Kernel] The quoted representation for `->` clauses changed from a tuple with two elements to a tuple with three elements to support metadata
@@ -195,7 +304,7 @@

 # v0.9.2 (2013-06-13)

-* enhancements
+* Enhancements
  * [ExUnit] `capture_io` now captures prompt by default
  * [Mix] Automatically import git dependencies from Rebar
  * [Mix] Support for dependencies directly from the umbrella application
@@ -203,7 +312,7 @@
  * [String] Add `String.contains?`
  * [URI] Implement `Binary.Chars` (aka `to_binary`) for `URI.Info`

-* bug fix
+* Bug fixes
  * [HashDict] Ensure HashDict uses exact match throughout its implementation
  * [IEx] Do not interpret ANSI codes in IEx results
  * [IEx] Ensure `--cookie` is set before accessing remote shell
@@ -211,21 +320,21 @@
  * [Mix] Fix usage of shell expressions in `Mix.Shell.cmd`
  * [Mix] Start the application by default on escripts

-* deprecations
+* Deprecations
  * [Regex] `Regex.index/2` is deprecated in favor `Regex.run/3`
  * [Kernel] `super` no longer supports implicit arguments

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Kernel] The `=~` operator now returns true or false instead of an index

 # v0.9.1 (2013-05-30)

-* enhancements
+* Enhancements
  * [IEx] Limit the number of entries kept in history and allow it to be configured
  * [Kernel] Add `String.start_with?` and `String.end_with?`
  * [Typespec] Allow keywords, e.g. `[foo: integer, bar: boolean | module]`, in typespecs

-* bug fix
+* Bug fixes
  * [Dict] `Enum.to_list` and `Dict.to_list` now return the same results for dicts
  * [IEx] Enable shell customization via the `IEx.Options` module
  * [Kernel] Fix a bug where `unquote_splicing` did not work on the left side of a stab op
@@ -236,12 +345,12 @@

 # v0.9.0 (2013-05-23)

-* enhancements
+* Enhancements
  * [ExUnit] `ExUnit.CaptureIO` now accepts an input to be used during capture
  * [IEx] Add support for .iex files that are loaded during shell's boot process
  * [IEx] Add `import_file/1` helper

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Enum] `Enum.Iterator` was replaced by the more composable and functional `Enumerable` protocol which supports reductions
  * [File] `File.iterator/1` and `File.biniterator/1` have been removed in favor of the safe `File.iterator!/1` and `File.biniterator!/1` ones
  * [Kernel] Erlang R15 is no longer supported
@@ -249,7 +358,7 @@

 # v0.8.3 (2013-05-22)

-* enhancements
+* Enhancements
  * [CLI] Flags `-p` and `-pr` fails if pattern match no files
  * [CLI] Support `--hidden` and `--cookie` flags for distributed Erlang
  * [Enum] Add `Enum.to_list/1`, `Enum.member?/2`, `Enum.uniq/2`, `Enum.max/1`, `Enum.max/2`, `Enum.min/1` and `Enum.min/2`
@@ -272,7 +381,7 @@
  * [Mix] Load beam files available at `MIX_PATH` on CLI usage
  * [String] Add `String.valid?` and `String.valid_character?`

-* bug fix
+* Bug fixes
  * [ExUnit] Handle exit messages from in ExUnit
  * [ExUnit] Failures on ExUnit's setup_all now invalidates all tests
  * [Kernel] Ensure we don't splice keyword args unecessarily
@@ -284,7 +393,7 @@
  * [Regex] Fix badmatch with `Regex.captures(%r/(.)/g, "cat")`
  * [URI] Downcase host and scheme and URIs

-* deprecations
+* Deprecations
  * [Code] `Code.eval` is deprecated in favor of `Code.eval_string`
  * [Exception] `Exception.format_entry` is deprecated in favor of `Exception.format_stacktrace_entry`
  * [ExUnit] `assert left inlist right` is deprecated in favor of `assert left in right`
@@ -293,7 +402,7 @@
  * [Kernel] `var_context` in quote was deprecated in favor of `context`
  * [Kernel] `Enum.at!` and `Dict.get!` is deprecated in favor of `Enum.fetch!` and `Dict.fetch!`

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Dict] `List.Dict` was moved to `ListDict`
  * [IO] `IO.gets`, `IO.getn` and friends now return binaries when reading from stdio
  * [Kernel] Precedence of `|>` has changed to lower to support constructs like `1..5 |> Enum.to_list`
@@ -301,7 +410,7 @@

 # v0.8.2 (2013-04-20)

-* enhancements
+* Enhancements
  * [ExUnit] Use ANSI escape codes in CLI output
  * [ExUnit] Include suite run time on CLI results
  * [ExUnit] Add support to doctests, allowing test cases to be generated from code samples
@@ -314,7 +423,7 @@
  * [Mix] Support `--cover` on mix test and `test_coverage` on Mixfiles
  * [Record] Each record now provides `Record.options` with the options supported by its `new` and `update` functions

-* bug fix
+* Bug fixes
  * [Binary] inspect no longer escapes standalone hash `#`
  * [IEx] The `h` helper can now retrieve docs for special forms
  * [Kernel] Record optimizations were not being triggered in functions inside the record module
@@ -322,11 +431,11 @@
  * [Kernel] Fix a bug where nested records could not use the Record[] syntax
  * [Path] Fix a bug on `Path.expand` when expanding paths starting with `~`

-* deprecations
+* Deprecations
  * [Kernel] `setelem/3` is deprecated in favor of `set_elem/3`
  * [Kernel] `function(:is_atom, 1)` is deprecated in favor of `function(is_atom/1)`

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Kernel] `unquote` now only applies to the closest quote. If your code contains a quote that contains another quote that calls unquote, it will no longer work. Use `Macro.escape` instead and pass your quoted contents up in steps, for example:

            quote do
@@ -341,7 +450,7 @@

 # v0.8.1 (2013-02-17)

-* enhancements
+* Enhancements
  * [ExUnit] Tests can now receive metadata set on setup/teardown callbacks
  * [ExUnit] Add support to ExUnit.CaseTemplate to share callbacks in between test cases
  * [IO] Add `IO.ANSI` to make it easy to write ANSI escape codes
@@ -354,13 +463,13 @@
  * [OptionParser] Switches are now overridden by default but can be kept in order if chosen
  * [Typespec] Better error reporting for invalid typespecs

-* bug fix
+* Bug fixes
  * [Mix] Allow Mix projects to be generated with just one letter

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Kernel] `before_compile` and `after_compile` callbacks now receive the environment as first argument instead of the module

-* deprecations
+* Deprecations
  * [ExUnit] Explicitly defined test/setup/teardown functions are deprecated
  * [Kernel] Tidy up and clean `quote` API
  * [Kernel] Old `:local.(args)` syntax is deprecated
@@ -368,7 +477,7 @@

 # v0.8.0 (2013-01-28)

-* enhancements
+* Enhancements
  * [Binary] Support `<< "string" :: utf8 >>` as in Erlang
  * [Binary] Support `\a` escape character in binaries
  * [Binary] Support syntax shortcut for specifying size in bit syntax
@@ -391,16 +500,16 @@
  * [String] Add `String.capitalize` and `String.slice`
  * [System] Add `System.tmp_dir`, `System.cwd` and `System.user_home`

-* bug fix
+* Bug fixes
  * [Kernel] `import` with `only` accepts functions starting with underscore
  * [String] `String.first` and `String.last` return nil for empty binaries
  * [String] `String.rstrip` and `String.lstrip` now verify if argument is a binary
  * [Typespec] Support `...` inside typespec's lists

-* backwards incompatible changes
+* Backwards incompatible changes
  * [Kernel] The AST now allows metadata to be attached to each node. This means the second item in the AST is no longer an integer (representing the line), but a keywords list. Code that relies on the line information from AST or that manually generate AST nodes need to be properly updated

-* deprecations
+* Deprecations
  * [Dict] Deprecate `Binary.Dict` and `OrdDict` in favor of `HashDict` and `ListDict`
  * [File] Deprecate path related functions in favor of the module `Path`
  * [Kernel] The `/>` operator has been deprecated in favor of `|>`
@@ -410,7 +519,7 @@

 # v0.7.2 (2012-12-04)

-* enhancements
+* Enhancements
  * [CLI] `--debug-info` is now true by default
  * [ExUnit] Make ExUnit exit happen in two steps allowing developers to add custom `at_exit` hooks
  * [IEx] Many improvements to helpers functions `h/1`, `s/1` and others
@@ -423,12 +532,12 @@
  * [Record] Record accessors are now optimized and can be up to 6x faster in some cases
  * [String] Support `\xXX` and `\x{HEX}` escape sequences in strings, char lists and regexes

-* bug fix
+* Bug fixes
  * [Bootstrap] Compiling Elixir source no longer fails if environment variables contain utf-8 entries
  * [IEx] IEx will now wait for all command line options to be processed before starting
  * [Kernel] Ensure proper stacktraces when showing deprecations

-* deprecations
+* Deprecations
  * [Enum] `Enum.qsort` is deprecated in favor of `Enum.sort`
  * [List] `List.sort` and `List.uniq` have been deprecated in favor of their `Enum` counterparts
  * [Record] Default-based generated functions are deprecated
@@ -436,7 +545,7 @@

 # v0.7.1 (2012-11-18)

-* enhancements
+* Enhancements
  * [IEx] Only show documented functions and also show docs for default generated functions
  * [IO] Add `IO.binread`, `IO.binwrite` and `IO.binreadline` to handle raw binary file operations
  * [ExUnit] Add support for user configuration at `HOME/.ex_unit.exs`
@@ -454,20 +563,20 @@
  * [Typespec] Define a default type `t` for protocols and records
  * [Typespec] Add support for the access protocol in typespecs

-* bug fix
+* Bug fixes
  * [Kernel] Fix an issue where variables inside clauses remained unassigned
  * [Kernel] Ensure `defoverridable` functions can be referred in many clauses
  * [Kernel] Allow keywords as function names when following a dot (useful when integrating with erlang libraries)
  * [File] File is opened by default on binary mode instead of utf-8

-* deprecations
+* Deprecations
  * [Behaviour] `defcallback/1` is deprecated in favor of `defcallback/2` which matches erlang `@callbacks`
  * [Enum] `Enum.times` is deprecated in favor of using ranges
  * [System] `halt` moved to `System` module

 # v0.7.0 (2012-10-20)

-* enhancements
+* Enhancements
  * [Behaviour] Add Behaviour with a simple callback DSL to define callbacks
  * [Binary] Add a Dict binary that converts its keys to binaries on insertion
  * [Binary] Optimize `Binary.Inspect` and improve inspect for floats
@@ -493,7 +602,7 @@
  * [Regex] Add `:return` option to `Regex.run` and `Regex.scan`
  * [String] Add a String module responsible for handling UTf-8 binaries

-* bug fix
+* Bug fixes
  * [File] `File.cp` and `File.cp_r` now preserves the file's mode
  * [IEx] Fix a bug where printing to `:stdio` on `IEx` was causing it to hang
  * [Macro] Fix a bug where quoted expressions were not behaving the same as their non-quoted counterparts
@@ -501,12 +610,12 @@
  * [Mix] Mix now exits with status 1 in case of failures
  * [Protocol] Avoid false positives on protocol dispatch (a bug caused the dispatch to be triggered to an invalid protocol)

-* backwards incompatible changes
+* Backwards incompatible changes
  * [ExUnit] `setup` and `teardown` callbacks now receives the test name as second argument
  * [Kernel] Raw function definition with `def/4`, `defp/4`, `defmacro/4`, `defmacrop/4` now evaluates all arguments. The previous behaviour was accidental and did not properly evaluate all arguments
  * [Kernel] Change tuple-related (`elem` and `setelem`), Enum functions (`find_index`, `nth!` and `times`) and List functions (List.key*) to zero-index

-* deprecations
+* Deprecations
  * [Code] `Code.require_file` and `Code.load_file` now expect the full name as argument
  * [Enum] `List.reverse/1` and `List.zip/2` were moved to `Enum`
  * [GenServer] Rename `GenServer.Behavior` to `GenServer.Behaviour`
@@ -516,14 +625,14 @@

 # v0.6.0 (2012-08-01)

-* incompatible changes
+* Backwards incompatible changes
  * [Kernel] Compile 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__`
  * [Kernel] Comprehensions syntax changed to be more compatible with Erlang behavior
  * [Kernel] loop and recur are removed in favor of recursion with named functions
  * [Module] Removed data functions in favor of unifying the attributes API

-* deprecations
+* Deprecations
  * [Access] The semantics of the access protocol were reduced from a broad query API to simple data structure key-based access
  * [ExUnit] Some assertions are deprecated in favor of simply using `assert()`
  * [File] `File.read_info` is deprecated in favor of `File.stat`
@@ -535,7 +644,7 @@
  * [Module] `Module.function_defined?` is deprecated in favor of `Module.defines?`
  * [Module] `Module.defined_functions` is deprecated in favor of `Module.definitions_in`

-* enhancements
+* Enhancements
  * [Enum] Enhance Enum protocol to support `Enum.count`
  * [Enum] Optimize functions when a list is given as collection
  * [Enum] Add `find_index`, `nth!` and others
@@ -19,11 +19,14 @@ INSTALL_PROGRAM = $(INSTALL) -m755
 define APP_TEMPLATE
 $(1): lib/$(1)/ebin/Elixir.$(2).beam lib/$(1)/ebin/$(1).app

-lib/$(1)/ebin/$(1).app:
-	$(Q) cd lib/$(1) && ../../bin/elixir -e "Mix.Server.start_link(:dev)" -r mix.exs -e "Mix.Task.run('compile.app')"
+lib/$(1)/ebin/$(1).app: lib/$(1)/mix.exs
+	$(Q) cd lib/$(1) && ../../bin/elixir -e "Mix.Sup.start_link()" -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)
 	@ echo "==> $(1) (compile)"
+	@ rm -rf lib/$(1)/ebin
 	$(Q) $$(ELIXIRC) "lib/$(1)/lib/**/*.ex" -o lib/$(1)/ebin

 test_$(1): $(1)
@@ -42,7 +45,9 @@ compile: lib/elixir/src/elixir.app.src erlang elixir

 lib/elixir/src/elixir.app.src: src/elixir.app.src
 	$(Q) rm -rf lib/elixir/src/elixir.app.src
-	$(Q) cp src/elixir.app.src 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

 erlang:
 	$(Q) cd lib/elixir && $(REBAR) compile
@@ -65,10 +70,10 @@ $(KERNEL): lib/elixir/lib/*.ex lib/elixir/lib/*/*.ex
 	$(Q) cd lib/elixir && $(REBAR) compile

 unicode: $(UNICODE)
-$(UNICODE): lib/elixir/priv/unicode.ex lib/elixir/priv/UnicodeData.txt lib/elixir/priv/NamedSequences.txt
+$(UNICODE): lib/elixir/unicode/unicode.ex lib/elixir/unicode/UnicodeData.txt lib/elixir/unicode/GraphemeBreakProperty.txt
 	@ echo "==> unicode (compile)";
 	@ echo "This step can take up to a minute to compile in order to embed the Unicode database"
-	$(Q) $(ELIXIRC) lib/elixir/priv/unicode.ex -o lib/elixir/ebin;
+	$(Q) $(ELIXIRC) lib/elixir/unicode/unicode.ex -o lib/elixir/ebin;

 $(eval $(call APP_TEMPLATE,ex_unit,ExUnit))
 $(eval $(call APP_TEMPLATE,eex,EEx))
@@ -10,11 +10,13 @@ If you want to contribute to Elixir or run it from source, clone this repository

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

 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.

-However, if tests fail, it is likely you have an outdated Erlang version (Elixir requires Erlang R16B or later). You can check your Erlang version by calling `erl` in the command line. You will see some information as follow:
+However, if tests fail, it is likely you have an outdated Erlang version (Elixir requires Erlang R16B or later). You can check your Erlang version by calling `erl` in the command line. You will see some information as follows:

    Erlang R16B (erts-5.10.1) [source] [64-bit] [smp:2:2] [rq:2] [async-threads:0] [hipe] [kernel-poll:false]

@@ -10,7 +10,7 @@ This document simply outlines the release process:

 4) Commit changes above with title "Release vVERSION"

-5) Push master and create tag from master branch
+5) Push master and create tag vVERSION from master branch

 6) Release new docs with `make release_docs`, move docs to `docs/stable`

@@ -20,7 +20,7 @@ This document simply outlines the release process:

 9) Merge master into stable branch and push it

-10) After release, bump versions and add `-dev` back
+10) After release, bump versions, add `-dev` back and commit

 11) `make release_docs` once again and push `elixir-lang.github.com`

@@ -1 +1 @@
-0.10.2
+0.11.2
@@ -73,8 +73,6 @@ done

 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-
-if [ -f "$HOME/.elixirrc" ]; then . "$HOME/.elixirrc"; fi
 if [ "$ELIXIR_NO_CLI" != "1" ]; then ERL="$ERL -s elixir start_cli"; fi

 if [ -f "$SCRIPT_PATH/../releases/RELEASES" ] && [ -f "$SCRIPT_PATH/erl" ]
@@ -38,4 +38,4 @@ readlink_f () {

 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-ELIXIR_NO_CLI=1 exec "$SCRIPT_PATH"/elixir --no-halt --erl "-nouser -s Elixir.IEx.CLI" +iex "$@"
+ELIXIR_NO_CLI=1 exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user Elixir.IEx.CLI" +iex "$@"
@@ -1,3 +1,3 @@
 #!/usr/bin/env elixir
 Mix.start
-Mix.CLI.run
+Mix.CLI.main
@@ -31,7 +31,7 @@ defmodule EEx.Compiler do
  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([]))
+    generate_buffer(t, buffer, scope, state)
  end

  defp generate_buffer([{ :middle_expr, line, _, chars }|t], buffer, [current|scope], state) do
@@ -68,7 +68,7 @@ defmodule EEx.Compiler do
    else
      key = length(state.dict)
      placeholder = '__EEX__(' ++ integer_to_list(key) ++ ');'
-      { current ++ placeholder ++ new_lines ++ chars, state.update_dict([{key, buffer}|&1]) }
+      { current ++ placeholder ++ new_lines ++ chars, state.update_dict(&[{key, buffer}|&1]) }
    end
  end

@@ -108,7 +108,7 @@ defmodule EEx.Compiler do
  end

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

  defp insert_quotes(other, _dict) do
@@ -103,7 +103,7 @@ defmodule EEx.Tokenizer do
    # 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, tokens } ->
+      { :ok, _line, tokens } ->
        tokens   = Enum.reverse(tokens)
        fn_index = fn_index(tokens)

@@ -136,7 +136,7 @@ defmodule EEx.Tokenizer do
  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
@@ -264,6 +264,21 @@ 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 "unicode" do
    template = """
      • <%= "•" %> •
@@ -17,7 +17,6 @@
  module=nil,              %% the current module
  function=nil,            %% the current function
  vars=[],                 %% a dict of defined variables and their alias
-  list_vars=nil,           %% a list of vars passed down to Macro.Env
  backup_vars=nil,         %% a copy of vars to be used on ^var
  temp_vars=nil,           %% a set of all variables defined in a particular assign
  clause_vars=nil,         %% a dict of all variables defined in a particular clause
@@ -26,6 +25,8 @@
  local=nil,               %% the scope to evaluate local functions against
  context_modules=[],      %% modules defined in the current context
  macro_aliases=[],        %% keep aliases defined inside a macro
+  macro_counter=0,         %% macros expansions counter
+  lexical_tracker=nil,     %% holds the lexical tracker pid
  aliases,                 %% an orddict with aliases by new -> old names
  file,                    %% the current scope filename
  requires,                %% a set with modules required
@@ -36,7 +37,7 @@
 }).

 -record(elixir_quote, {
-  line=0,
+  line=nil,
  context=nil,
  vars_hygiene=true,
  aliases_hygiene=true,
@@ -46,6 +47,13 @@
  escape=false
 }).

+-record(elixir_tokenizer, {
+  file,
+  terminators=[],
+  check_terminators=true,
+  existing_atoms_only=false
+}).
+
 %% Introspection
 -define(defs(Kind), Kind == def; Kind == defp; Kind == defmacro; Kind == defmacrop).

@@ -11,8 +11,6 @@ defprotocol Access do
  following built-in types: keywords, records and functions.
  """

-  @only [List, Record, Atom]
-
  @doc """
  Receives the element being accessed and the access item.
  """
@@ -22,6 +20,7 @@ end
 defimpl Access, for: List do
  @doc """
  Access the given key in a tuple list.
+  The key is found via the `===` operator.

  ## Examples

@@ -34,14 +33,10 @@ defimpl Access, for: List do
      "★☆"

  """
+  def access(dict, key)
+  def access([{ key, value }|_], key), do: value
+  def access([{ _, _ }|t], key), do: access(t, key)
  def access([], _key), do: nil
-
-  def access(list, key) do
-    case :lists.keyfind(key, 1, list) do
-      { ^key, value } -> value
-      false -> nil
-    end
-  end
 end

 defimpl Access, for: Atom do
@@ -1,40 +1,40 @@
 defmodule Application.Behaviour do
  @moduledoc """
-  This module is a convenience to define application module callbacks.
+  Default callbacks for applications.

  In Erlang/OTP, an application is a component that can be started
-  and stopped as a unit, and which can be re-used in other systems
-  as well.
+  and stopped as a unit, and which can be reused in other systems.

-  The first step to achieve this is to define an application specification.
+  The first step in creating an application is to define an application specification.
  For example, if your application is named `:my_app`, an app specification
  should exist at `ebin/my_app.app`. This file is usually defined by
  build tools like Mix.

-  Then, with the app specification in hands, we must also define an
-  application module callback that controls how to start and stop
-  such applications. This module is about defining such callbacks.
+  With the app specification in hand, we must define
+  application module callbacks that control how to start and stop
+  instances of the application. This module is about defining such callbacks.

-  There are two callbacks required to be implemented:
+  There are two callbacks which must be implemented:

-  1. `start(type, args)` - It must return `{ :ok, pid }` or
+  1. `start(type, args)` - must return `{ :ok, pid }` or
     `{ :ok, pid, state }`, where `pid` is the process identifier
-     of the supervisor tree root;
+     of the supervisor tree root and `state` is application defined 
+     state information;

-  2. `stop(state)` receives the state returned by `start` and should
-     do any necessary cleaning up. Notice that shutting down the supervisor
+  2. `stop(state)` - receives the `state` returned by `start` and should
+     do any necessary clean up. Notice that shutting down the supervisor
     is automatically handled by the VM;

-  When using this module, it simply tags the module behaviour as
-  `:application` and defines a default `stop/1` callback. The `start/2`
-  still needs to be defined by the user.
+  When using this module, it tags the module behaviour as
+  `:application` and provides a default `stop/1` callback. The `start/2` callback
+  still needs to be implemented by the user.

  You can learn more about the `:application` module, the application
-  specification and the application module callbacks below:
+  specification and the application module callbacks from these sources:

-  http://www.erlang.org/doc/man/application.html
-  http://www.erlang.org/doc/design_principles/applications.html
-  http://learnyousomeerlang.com/building-otp-applications
+  * http://www.erlang.org/doc/man/application.html
+  * http://www.erlang.org/doc/design_principles/applications.html
+  * http://learnyousomeerlang.com/building-otp-applications

  ## Example

@@ -102,4 +102,4 @@ defmodule Application.Behaviour do
      defoverridable [stop: 1]
    end
  end
-end
+end
@@ -1,12 +1,12 @@
 defmodule Behaviour do
  @moduledoc """
-  A convenience module for defining behaviours.
+  Utilities for defining behaviour intefaces.
+
  Behaviours can be referenced by other modules
-  in order to ensure they implement the proper
-  callbacks.
+  to ensure they implement required callbacks.

  For example, you can specify the `URI.Parser`
-  behaviour as follow:
+  behaviour as follows:

      defmodule URI.Parser do
        use Behaviour
@@ -18,7 +18,7 @@ defmodule Behaviour do
        defcallback default_port() :: integer
      end

-  And then a specific module may use it as:
+  And then a module may use it as:

      defmodule URI.HTTP do
        @behaviour URI.Parser
@@ -26,24 +26,25 @@ defmodule Behaviour do
        def parse(info), do: info
      end

-  In case the behaviour changes or URI.HTTP does
+  If the behaviour changes or `URI.HTTP` does
  not implement one of the callbacks, a warning
  will be raised.

  ## Implementation

-  Behaviours since Erlang R15 must be defined via
+  Since Erlang R15, behaviours must be defined via
  `@callback` attributes. `defcallback` is a simple
  mechanism that defines the `@callback` attribute
-  according to the type specification and also allows
-  docs and defines a custom function signature.
+  according to the given type specification. `defcallback` allows
+  documentsion to be created for the callback and defines 
+  a custom function signature.

  The callbacks and their documentation can be retrieved
  via the `__behaviour__` callback function.
  """

  @doc """
-  Defines a callback according to the given type specification.
+  Define a function callback according to the given type specification.
  """
  defmacro defcallback({ :::, _, [fun, return] }) do
    do_defcallback(fun, return, __CALLER__)
@@ -54,7 +55,7 @@ defmodule Behaviour do
  end

  @doc """
-  Defines a macro callback according to the given type specification.
+  Define a macro callback according to the given type specification.
  """
  defmacro defmacrocallback({ :::, _, [fun, return] }) do
    do_defmacrocallback(fun, return, __CALLER__)
@@ -6,24 +6,24 @@ defmodule Code do
  end

  @moduledoc """
-  The Code module is responsible for managing code compilation,
-  code evaluation and code loading.
+  Utilities for managing code compilation, code evaluation and code loading.

-  It complements [Erlang's code module](http://www.erlang.org/doc/man/code.html)
+  This module complements [Erlang's code module](http://www.erlang.org/doc/man/code.html)
  to add behavior which is specific to Elixir.

  """

  @doc """
-  Returns all loaded files.
+  List all loaded files.
  """
  def loaded_files do
    :elixir_code_server.call :loaded
  end

  @doc """
-  Removes the given files from the loaded files list.
-  The modules defined in the file are not removed,
+  Remove 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.
  """
@@ -32,7 +32,8 @@ defmodule Code do
  end

  @doc """
-  Appends a path to the Erlang VM code path.
+  Append a path to the Erlang VM code path.
+
  The path is expanded with `Path.expand/1` before being appended.
  """
  def append_path(path) do
@@ -40,7 +41,8 @@ defmodule Code do
  end

  @doc """
-  Prepends a path to the Erlang VM code path.
+  Prepend a path to the Erlang VM code path.
+
  The path is expanded with `Path.expand/1` before being prepended.
  """
  def prepend_path(path) do
@@ -48,7 +50,8 @@ defmodule Code do
  end

  @doc """
-  Deletes a path from the Erlang VM code path.
+  Delete a path from the Erlang VM code path.
+
  The path is expanded with `Path.expand/1` before being deleted.
  """
  def delete_path(path) do
@@ -56,9 +59,12 @@ defmodule Code do
  end

  @doc """
-  Evaluates the contents given by `string`. The second argument is 
-  a keyword list of variable bindings, followed by a keyword list of
-  environment options. Those options can be:
+  Evaluate 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. 
+  
+  Those options can be:

  * `:file` - the file to be considered in the evaluation
  * `:line` - the line on which the script starts
@@ -83,9 +89,12 @@ defmodule Code do
  etc.

  Returns a tuple of the form `{ value, binding }`,
-  where `value` is the the value returned from evaluating `string`; `binding`
-  is a keyword list with the value of all variable bindings after evaluating
-  `string`. If an error occurs while evaluating `string` an exception will be raised.
+  where `value` is the 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.

  ## Examples

@@ -95,7 +104,7 @@ defmodule Code do
      iex> Code.eval_string("c = a + b", [a: 1, b: 2], __ENV__)
      {3, [a: 1, b: 2, c: 3]}

-      iex> Code.eval_string("a = a + b", [a: 1, b: 2])          
+      iex> Code.eval_string("a = a + b", [a: 1, b: 2])
      {3, [a: 3, b: 2]}

  For convenience, you can pass `__ENV__` as the `opts` argument and
@@ -123,7 +132,7 @@ defmodule Code do
  end

  @doc """
-  Evaluates the quoted contents.
+  Evaluate the quoted contents.

  See `eval_string/3` for a description of arguments and return values.

@@ -166,10 +175,10 @@ defmodule Code do
  end

  defp validate_requires(kind, requires) do
-    valid = is_list(requires) and Enum.all?(requires, is_atom(&1))
+    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]"
+      raise ArgumentError, message: "expected :#{kind} option given to eval in the format: [module]"
    end
  end

@@ -179,7 +188,7 @@ defmodule Code do
    end)

    unless valid do
-      raise ArgumentError, "expected :#{kind} option given to eval in the format: [{ module, module }]"
+      raise ArgumentError, message: "expected :#{kind} option given to eval in the format: [{ module, module }]"
    end
  end

@@ -191,12 +200,14 @@ defmodule Code do
    end)

    unless valid do
-      raise ArgumentError, "expected :#{kind} option given to eval in the format: [{ module, [{ name, arity }] }]"
+      raise ArgumentError, message: "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 }`
+  Convert the given string to its quoted form. 
+  
+  Returns `{ :ok, quoted_form }`
  if it succeeds, `{ :error, { line, error, token } }` otherwise.

  ## Options
@@ -209,10 +220,10 @@ defmodule Code do
  * `:existing_atoms_only` - When `true`, raises an error
    when non-existing atoms are found by the tokenizer.

-  ## Macro.to_string/1
+  ## Macro.to_string/2

  The opposite of converting a string to its quoted form is
-  `Macro.to_string/1`, which converts a quoted form to a string/binary
+  `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
@@ -227,7 +238,9 @@ defmodule Code do
  end

  @doc """
-  Converts the given string to its quoted form. It returns the ast if it succeeds,
+  Convert the given string to its quoted form. 
+  
+  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.
@@ -246,7 +259,9 @@ defmodule Code do
  defp unpack_quote(line, forms),                            do: { :__block__, [line: line], forms }

  @doc """
-  Loads the given `file`. Accepts `relative_to` as an argument to tell where
+  Load 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.
@@ -266,9 +281,11 @@ defmodule Code do
  end

  @doc """
-  Requires the given `file`. Accepts `relative_to` as an argument to tell where
+  Require 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.
+  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
@@ -294,7 +311,8 @@ defmodule Code do
  end

  @doc """
-  Loads the compilation options from the code server.
+  Load the compilation options from the code server.
+
  Check `compiler_options/1` for more information.
  """
  def compiler_options do
@@ -302,8 +320,9 @@ defmodule Code do
  end

  @doc """
-  Sets compilation options. These options are global
-  since they are stored by Elixir's Code Server.
+  Set compilation options. 
+
+  These options are global since they are stored by Elixir's Code Server.

  Available options are:

@@ -312,7 +331,7 @@ defmodule Code do

  * `: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;
+    code, `false` by default;

  * `:ignore_module_conflict` - when `true`, override modules that were already defined
    without raising errors, `false` by default;
@@ -325,7 +344,9 @@ defmodule Code do
  end

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

@@ -336,7 +357,9 @@ defmodule Code do
  end

  @doc """
-  Compiles the quoted expression and returns a list of tuples where
+  Compile the quoted expression. 
+  
+  Returns a list of tuples where
  the first element is the module name and the second one is its
  binary.
  """
@@ -345,8 +368,10 @@ defmodule Code do
  end

  @doc """
-  Ensures the given module is loaded. If the module is already
-  loaded, it works as no-op. If the module was not yet loaded,
+  Ensure 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
@@ -362,7 +387,7 @@ defmodule Code do
  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` 
+  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.

@@ -387,17 +412,21 @@ defmodule Code do
  end

  @doc """
-  Similar to `ensure_loaded/1`, but returns a boolean in case
-  it could be ensured or not.
+  Ensure the given module is loaded.
+
+  Similar to `ensure_loaded/1`, but returns `true` if the module
+  is already loaded or was successfully loaded. Returns `false` otherwise.
  """
  def ensure_loaded?(module) do
    match?({ :module, ^module }, ensure_loaded(module))
  end

  @doc """
-  Ensures the given module is compiled and loaded. If the module
+  Ensure 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 
+  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
@@ -425,8 +454,11 @@ defmodule Code do
  end

  @doc """
-  Similar to `ensure_compiled/1`, but returns a boolean in case
-  it could be ensured or not.
+  Ensure 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.
  """
  def ensure_compiled?(module) do
    match?({ :module, ^module }, ensure_compiled(module))
@@ -31,6 +31,11 @@ defmodule Dict do
        IO.puts "#{k}: #{v}"
      end)

+  ## Match
+
+  Dictionaries are required to implement all operations
+  using the match (`===`) operator. Any deviation from
+  this behaviour should be avoided and explicitly documented.
  """

  use Behaviour
@@ -420,7 +425,7 @@ defmodule Dict do

  @doc """
  Returns a new dict where only the keys in `keys` from `dict` are
-  included. 
+  included.
  Any non-member keys are ignored.

  ## Examples
@@ -458,8 +463,8 @@ defmodule Dict do
  end

  @doc """
-  Check if two dicts are equal. If the dicts are of different types, they are
-  first converted to lists.
+  Check if two dicts are equal using `===`. If the dicts are
+  of different types, they are first converted to lists.

  ## Examples

@@ -2,7 +2,7 @@ defmodule Dict.Behaviour do
  @moduledoc """
  This module makes it easier to create your own `Dict` compliant
  module, by providing default implementations for some required functions.
-  
+
  Usage:

      defmodule MyDict do
@@ -13,16 +13,16 @@ defmodule Dict.Behaviour do
        # override default implementations if needed
      end

-  The client module must contain following functions: `size/1`, `fetch/2`, 
+  The client module must contain following functions: `size/1`, `fetch/2`,
  `put/3`, `update/4`, `delete/2` and `reduce/3`. All of them are part of
  the Dict behaviour, so no extra functions are actually required.

-  Based on these functions, `Dict.Behaviour` generates default implementations 
+  Based on these functions, `Dict.Behaviour` generates default implementations
  for other functions such as `drop`, `take`, etc. All of the functions are
  defined as overridable, so you can provide your own implementation if
  needed.

-  If you implement `new/0` and `new/1` functions, you can also test your custom 
+  If you implement `new/0` and `new/1` functions, you can also test your custom
  module via `Dict` doctests:

      defmodule MyDict do
@@ -38,11 +38,10 @@ defmodule Dict.Behaviour do
      end

  """
-
  defmacro __using__(_) do
    quote do
      @behaviour Dict
-      
+
      def get(dict, key, default // nil) do
        case fetch(dict, key) do
          { :ok, value } -> value
@@ -58,29 +57,29 @@ defmodule Dict.Behaviour do
        end
      end
      defoverridable fetch!: 2
- 
+
      def has_key?(dict, key) do
        match? { :ok, _ }, fetch(dict, key)
      end
      defoverridable has_key?: 2
- 
+
      def put_new(dict, key, value) do
        update(dict, key, value, fn(v) -> v end)
      end
      defoverridable put_new: 3
- 
+
      def drop(dict, []), do: dict

      def drop(dict, [key|keys]) do
        drop(delete(dict, key), keys)
      end
      defoverridable drop: 2
- 
+
      def take(dict, keys) do
        take(dict, keys, new)
      end
      defoverridable take: 2
- 
+
      defp take(_dict, [], acc), do: acc
      defp take(dict, [key|keys], acc) do
        case fetch(dict, key) do
@@ -88,20 +87,21 @@ defmodule Dict.Behaviour do
          :error -> take(dict, keys, acc)
        end
      end
- 
+
      def to_list(dict), do: reduce(dict, [], &[&1|&2]) |> Enum.reverse
      defoverridable to_list: 1
- 
+
      def keys(dict), do: reduce(dict, [], fn({k, _}, acc) -> [k | acc] end) |> Enum.reverse
      defoverridable keys: 1
- 
+
      def values(dict), do: reduce(dict, [], fn({_, v}, acc) -> [v | acc] end) |> Enum.reverse
      defoverridable values: 1
- 
+
      def equal?(dict1, dict2) do
+        import Kernel, except: [size: 1]
        case size(dict1) == size(dict2) do
          false -> false
-          true -> 
+          true ->
            try do
              reduce(dict1, nil, fn({ k, v }, _acc) ->
                unless fetch(dict2, k) == { :ok, v }, do: throw(:error)
@@ -113,7 +113,7 @@ defmodule Dict.Behaviour do
        end
      end
      defoverridable equal?: 2
- 
+
      def merge(dict, enumerable, callback // fn(_k, _v1, v2) -> v2 end) do
        Enum.reduce(enumerable, dict, fn({key, value}, acc) ->
          update(acc, key, value, fn(v1) -> callback.(key, v1, value) end)
@@ -122,4 +122,4 @@ defmodule Dict.Behaviour do
      defoverridable merge: 2, merge: 3
    end
  end
-end
+end
@@ -15,8 +15,6 @@ defprotocol Enumerable do
  element in the collection and cons'ing the element with the accumulated list.
  """

-  @only [List, Record, Function]
-
  @doc """
  This function performs the reducing operation on a given collection. It
  returns the accumulated value of applying the given function `fun` on every
@@ -40,6 +38,7 @@ defprotocol Enumerable do

  @doc """
  The function is used to check if a value exists within the collection.
+  Membership should be tested with the match (`===`) operator.
  """
  def member?(collection, value)

@@ -89,6 +88,10 @@ defmodule Enum do
  @doc """
  Checks if `value` exists within the `collection`.

+  Membership is tested with the match (`===`) operator although
+  enumerables like ranges may include floats inside the given
+  range.
+
  ## Examples

      iex> Enum.member?(1..10, 5)
@@ -212,8 +215,6 @@ defmodule Enum do
  Finds the element at the given index (zero-based).
  Returns `default` if index is out of bounds.

-  Expects an ordered collection.
-
  ## Examples

      iex> Enum.at([2, 4, 6], 0)
@@ -283,7 +284,11 @@ defmodule Enum do

  @doc """
  Drops the first `count` items from `collection`.
-  Expects an ordered collection.
+
+  A negative value `count` can be given, which means
+  the collection is enumerated once to retrieve the
+  proper index and the remaining of the calculation
+  is done from the end.

  ## Examples

@@ -309,13 +314,11 @@ defmodule Enum do
  end

  def drop(collection, count) when count < 0 do
-    { list, count } = iterate_and_count(collection, count)
-    drop(list, count)
+    do_take_reverse(reverse(collection), abs(count), [])
  end

  @doc """
  Drops items at the beginning of `collection` while `fun` returns `true`.
-  Expects an ordered collection.

  ## Examples

@@ -386,7 +389,9 @@ defmodule Enum do
  Finds the element at the given index (zero-based).
  Returns `{ :ok, element }` if found, otherwise `:error`.

-  Expects an ordered collection.
+  A negative index can be passed, which means the collection is
+  iterated once and the index is counted from the end (i.e.
+  `-1` fetches the last element).

  ## Examples

@@ -418,8 +423,7 @@ defmodule Enum do
  end

  def fetch(collection, n) when n < 0 do
-    { list, count } = iterate_and_count_oob(collection, n)
-    if count >= 0, do: fetch(list, count), else: :error
+    fetch(reverse(collection), abs(n + 1))
  end

  @doc """
@@ -473,7 +477,7 @@ defmodule Enum do

  ## Examples

-      iex> Enum.filter_map([1, 2, 3], fn(x) -> rem(x, 2) == 0 end, &1 * 2)
+      iex> Enum.filter_map([1, 2, 3], fn(x) -> rem(x, 2) == 0 end, &(&1 * 2))
      [4]

  """
@@ -556,8 +560,6 @@ defmodule Enum do
  Similar to `find/3`, but returns the index (zero-based)
  of the element instead of the element itself.

-  Expects an ordered collection.
-
  ## Examples

      iex> Enum.find_index([2, 4, 6], fn(x) -> rem(x, 2) == 1 end)
@@ -648,14 +650,9 @@ defmodule Enum do

  """
  @spec join(t) :: String.t
-  @spec join(t, String.t | char_list) :: String.t | char_list
+  @spec join(t, String.t) :: String.t
  def join(collection, joiner // "")

-  def join(collection, joiner) when is_list(joiner) do
-    IO.write "Enum.join/2 with a char list is deprecated, please use do an explicit conversion instead\n#{Exception.format_stacktrace}"
-    :unicode.characters_to_list join(collection, :unicode.characters_to_binary(joiner))
-  end
-
  def join(collection, joiner) when is_binary(joiner) do
    Enumerable.reduce(collection, "", fn
      entry, ""  -> to_string(entry)
@@ -708,14 +705,9 @@ defmodule Enum do

  """
  @spec map_join(t, (element -> any)) :: String.t
-  @spec map_join(t, String.t | char_list, (element -> any)) :: String.t | char_list
+  @spec map_join(t, String.t, (element -> any)) :: String.t
  def map_join(collection, joiner // "", mapper)

-  def map_join(collection, joiner, mapper) when is_list(joiner) do
-    IO.write "Enum.map_join/3 with a char list is deprecated, please use do an explicit conversion instead\n#{Exception.format_stacktrace}"
-    :unicode.characters_to_list map_join(collection, :unicode.characters_to_binary(joiner), mapper)
-  end
-
  def map_join(collection, joiner, mapper) when is_binary(joiner) do
    Enumerable.reduce(collection, "", fn
      entry, ""  -> to_string(mapper, entry)
@@ -902,8 +894,8 @@ defmodule Enum do
  end

  def sort(collection) do
-    fun = &1 <= &2
-    Enumerable.reduce(collection, [], sort_reducer(&1, &2, fun)) |>
+    fun = &(&1 <= &2)
+    Enumerable.reduce(collection, [], &sort_reducer(&1, &2, fun)) |>
      sort_terminator(fun)
  end

@@ -922,7 +914,7 @@ defmodule Enum do
  end

  def sort(collection, fun) do
-    Enumerable.reduce(collection, [], sort_reducer(&1, &2, fun)) |>
+    Enumerable.reduce(collection, [], &sort_reducer(&1, &2, fun)) |>
      sort_terminator(fun)
  end

@@ -969,8 +961,7 @@ defmodule Enum do
  end

  def split(collection, count) when count < 0 do
-    { list, count } = iterate_and_count(collection, count)
-    split(list, count)
+    do_split_reverse(reverse(collection), abs(count), [])
  end

  @doc """
@@ -998,8 +989,12 @@ defmodule Enum do
  end

  @doc """
-  Takes the first `count` items from the collection. Expects an ordered
-  collection.
+  Takes the first `count` items from the collection.
+
+  A negative value `count` can be passed, which means
+  the collection is enumerated once to retrieve the
+  proper index and the remaining of the calculation
+  is done from the end.

  ## Examples

@@ -1037,13 +1032,36 @@ defmodule Enum do
  end

  def take(collection, count) when count < 0 do
-    { list, count } = iterate_and_count(collection, count)
-    take(list, count)
+    do_drop(reverse(collection), abs(count)) |> :lists.reverse
+  end
+
+  @doc """
+  Returns a collection of every `nth` items in the collection,
+  starting with the first.
+
+  ## Examples
+
+      iex> Enum.take_every(1..10, 2)
+      [1, 3, 5, 7, 9]
+
+  """
+  @spec take_every(t, integer) :: list
+  def take_every(_collection, 0), do: []
+  def take_every(collection, nth) do
+    res = Enumerable.reduce(collection, nil, fn
+      x, { acc, ^nth } -> { [x | acc], 1 }
+      _, { acc, count } -> { acc, count + 1 }
+      x, nil -> { [x], 1 }
+    end)
+
+    case res do
+      nil -> []
+      { list, _ } -> :lists.reverse(list)
+    end
  end

  @doc """
  Takes the items at the beginning of `collection` while `fun` returns `true`.
-  Expects an ordered collection.

  ## Examples

@@ -1169,12 +1187,6 @@ defmodule Enum do
    reduce(collection, &Kernel.max(&1, &2))
  end

-  @doc false
-  def max(coll, fun) do
-    IO.write "Enum.max/2 is deprecated, please use Enum.max_by/2 instead\n#{Exception.format_stacktrace}"
-    max_by(coll, fun)
-  end
-
  @doc """
  Returns the maximum value as calculated by the given function.
  Raises `EmptyError` if the collection is empty.
@@ -1229,12 +1241,6 @@ defmodule Enum do
    reduce(collection, &Kernel.min(&1, &2))
  end

-  @doc false
-  def min(coll, fun) do
-    IO.write "Enum.min/2 is deprecated, please use Enum.min_by/2 instead\n#{Exception.format_stacktrace}"
-    min_by(coll, fun)
-  end
-
  @doc """
  Returns the minimum value as calculated by the given function.
  Raises `EmptyError` if the collection is empty.
@@ -1320,7 +1326,7 @@ defmodule Enum do

  """
  @spec chunks(t, non_neg_integer, non_neg_integer) :: [list]
-  @spec chunks(t, non_neg_integer, non_neg_integer, list) :: [list]
+  @spec chunks(t, non_neg_integer, non_neg_integer, list | nil) :: [list]
  def chunks(coll, n, step, pad // nil) when n > 0 and step > 0 do
    { acc, buffer, i } =
      Enumerable.reduce(coll, { [], [], 0 }, fn
@@ -1371,12 +1377,17 @@ defmodule Enum do
  @doc """
  Returns a subset list of the given collection. Dropping elements
  until element position `start`, then taking `count` elements.
-  Expects an ordered collection.
+
+  ## Examples
+
+      iex> Enum.slice(1..100, 5, 10)
+      [6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
+
  """
-  @spec slice(t, integer, integer) :: list
+  @spec slice(t, integer, non_neg_integer) :: list

  def slice(coll, start, count) when start < 0 do
-    { list, new_start } = iterate_and_count_oob(coll, start)
+    { list, new_start } = iterate_and_count(coll, start)
    if new_start >= 0, do: slice(list, new_start, count)
  end

@@ -1408,6 +1419,41 @@ defmodule Enum do
    :enum_slice -> []
  end

+  @doc """
+  Returns a subset list of the given collection. Dropping elements
+  until element position `range.first`, then taking elements until element
+  position `range.last` (inclusive).
+
+  Positions are calculated by adding the number of items in the collection to
+  negative positions (so position -3 in a collection with count 5 becomes
+  position 2).
+
+  The first position (after adding count to negative positions) must be smaller
+  or equal to the last position.
+
+  ## Examples
+
+      iex> Enum.slice(1..100, 5..10)
+      [6, 7, 8, 9, 10, 11]
+
+  """
+  def slice(coll, first..last) when first >= 0 and last >= 0 do
+    # Simple case, which works on infinite collections
+    if last - first >= 0 do
+      slice(coll, first, last - first + 1)
+    end
+  end
+
+  def slice(coll, first..last) do
+    { list, count } = iterate_and_count(coll, 0)
+    corr_first = if first >= 0, do: first, else: first + count
+    corr_last = if last >= 0, do: last, else: last + count
+    length = corr_last - corr_first + 1
+    if corr_first >= 0 and length > 0 do
+      slice(list, corr_first, length)
+    end
+  end
+
  ## Helpers

  @compile { :inline, chunks_n: 5, chunks_step: 4, to_string: 2 }
@@ -1430,23 +1476,12 @@ defmodule Enum do
    { acc, buffer, i }
  end

-  defp iterate_and_count_oob(collection, count) do
-    { list, total_items } = do_iterate_and_count(collection)
-    { list, total_items - abs(count) }
+  defp iterate_and_count(collection, count) when is_list(collection) do
+    { collection, length(collection) - abs(count) }
  end

  defp iterate_and_count(collection, count) do
-    { list, total_items } = do_iterate_and_count(collection)
-    { list, Kernel.max(0, total_items - abs(count)) }
-  end
-
-  defp do_iterate_and_count(collection) when is_list(collection) do
-    { collection, length(collection) }
-  end
-
-  defp do_iterate_and_count(collection) do
-    reducer = fn(x, acc) -> { x, acc + 1 } end
-    map_reduce(collection, 0, reducer)
+    map_reduce(collection, -abs(count), fn(x, acc) -> { x, acc + 1 } end)
  end

  defp to_string(mapper, entry) do
@@ -1686,6 +1721,18 @@ defmodule Enum do
    { :lists.reverse(acc), [] }
  end

+  defp do_split_reverse([h|t], counter, acc) when counter > 0 do
+    do_split_reverse(t, counter - 1, [h|acc])
+  end
+
+  defp do_split_reverse(list, 0, acc) do
+    { :lists.reverse(list), acc }
+  end
+
+  defp do_split_reverse([], _, acc) do
+    { [], acc }
+  end
+
  ## split_while

  defp do_split_while([h|t], fun, acc) do
@@ -1714,6 +1761,18 @@ defmodule Enum do
    []
  end

+  defp do_take_reverse([h|t], counter, acc) when counter > 0 do
+    do_take_reverse(t, counter - 1, [h|acc])
+  end
+
+  defp do_take_reverse(_list, 0, acc) do
+    acc
+  end
+
+  defp do_take_reverse([], _, acc) do
+    acc
+  end
+
  ## take_while

  defp do_take_while([h|t], fun) do
@@ -1796,8 +1855,9 @@ defimpl Enumerable, for: Function do
  end

  def member?(function, value) do
-    function.(false, fn(entry, _) ->
-      if entry === value, do: throw(:function_member?), else: false
+    function.(false, fn
+      ^value, _ -> throw(:function_member?)
+      _, _ -> false
    end)
  catch
    :function_member? -> true
@@ -39,6 +39,12 @@ defexception CaseClauseError, [actual: nil] do
  end
 end

+defexception TryClauseError, [actual: nil] do
+  def message(exception) do
+    "no try clause matching: #{inspect(exception.actual)}"
+  end
+end
+
 defexception BadArityError, [function: nil, args: nil] do
  def message(exception) do
    "bad arity error: #{inspect(exception.function)} called with #{inspect(exception.args)}"
@@ -146,6 +152,10 @@ defmodule Exception do
    CaseClauseError[actual: actual]
  end

+  def normalize({ :try_clause, actual }) do
+    TryClauseError[actual: actual]
+  end
+
  def normalize(:undef) do
    { mod, fun, arity } = from_stacktrace(:erlang.get_stacktrace)
    UndefinedFunctionError[module: mod, function: fun, arity: arity]
@@ -266,6 +276,8 @@ defmodule Exception do
      "Foo.bar/1"
      iex> Exception.format_mfa Foo, :bar, []
      "Foo.bar()"
+      iex> Exception.format_mfa nil, :bar, []
+      "nil.bar()"

  """
  def format_mfa(module, fun, arity) do
@@ -277,12 +289,14 @@ defmodule Exception do

    if is_list(arity) do
      inspected = lc x inlist arity, do: inspect(x)
-      "#{inspect module}.#{fun}(#{Enum.join(inspected, ", ")})"
+      "#{format_module module}#{fun}(#{Enum.join(inspected, ", ")})"
    else
-      "#{inspect module}.#{fun}/#{arity}"
+      "#{format_module module}#{fun}/#{arity}"
    end
  end

+  defp format_module(mod), do: "#{inspect mod}."
+
  @doc """
  Formats the given file and line as shown in stacktraces.
  If any of the values are nil, they are omitted.
@@ -47,13 +47,6 @@ defexception File.CopyError, [reason: nil, action: "", source: nil, destination:
  end
 end

-defexception File.IteratorError, reason: nil do
-  def message(exception) do
-    formatted = iolist_to_binary(:file.format_error(reason exception))
-    "error during file iteration: #{formatted}"
-  end
-end
-
 defmodule File do
  @moduledoc """
  This module contains functions to manipulate files.
@@ -488,7 +481,7 @@ defmodule File do
        case F.list_dir(src) do
          { :ok, files } ->
            case mkdir(dest) do
-              success in [:ok, { :error, :eexist }] ->
+              success when success in [:ok, { :error, :eexist }] ->
                Enum.reduce(files, [dest|acc], fn(x, acc) ->
                  do_cp_r(FN.join(src, x), FN.join(dest, x), callback, acc)
                end)
@@ -945,7 +938,7 @@ defmodule File do
  """
  def ls(path // ".") do
    case F.list_dir(path) do
-      { :ok, file_list } -> { :ok, Enum.map(file_list, to_string(&1)) }
+      { :ok, file_list } -> { :ok, Enum.map(file_list, &to_string(&1)) }
      { :error, _ } = error -> error
    end
  end
@@ -980,7 +973,7 @@ defmodule File do
  of bytes given by `line_or_bytes`.

  The returned stream will fail for the same reasons as `File.open!`.
-  Note that the file is opened only when streaming begins.
+  Note that the file is opened only and every time streaming begins.
  """
  def stream!(file, mode // [], line_or_bytes // :line) do
    fn(acc, fun) ->
@@ -999,7 +992,7 @@ defmodule File do
  of bytes given by `line_or_bytes`.

  The returned stream will fail for the same reasons as `File.open!`.
-  Note that the file is opened only when streaming begins.
+  Note that the file is opened only and every time streaming begins.
  """
  def binstream!(file, mode // [], line_or_bytes // :line) do
    fn(fun, acc) ->
@@ -0,0 +1,83 @@
+defmodule Float do
+  @moduledoc """
+  Functions for working with floating point numbers.
+  """
+
+  @doc """
+  Parses a binary into a float. 
+  
+  If successful, returns a tuple of the form `{ float, remainder_of_binary }`.
+  Otherwise `:error`.
+
+  ## 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) when is_binary(binary) do
+    case Integer.parse binary do
+      :error -> :error
+      { integer_part, after_integer } -> parse after_integer, integer_part
+    end
+  end
+
+  # Dot followed by digit is required afterwards or we are done
+  defp parse(<< ?., char, rest :: binary >>, int) when char in ?0..?9 do
+    parse(rest, char - ?0, 1, int)
+  end
+
+  defp parse(rest, int) do
+    { :erlang.float(int), rest }
+  end
+
+  # Handle decimal points
+  defp parse(<< char, rest :: binary >>, float, decimal, int) when char in ?0..?9 do
+    parse rest, 10 * float + (char - ?0), decimal + 1, int
+  end
+
+  defp parse(<< ?e, after_e :: binary >>, float, decimal, int) do
+    case Integer.parse after_e do
+      :error ->
+        # Note we rebuild the binary here instead of breaking it apart at
+        # the function clause because the current approach copies a binary
+        # just on this branch. If we broke it apart in the function clause,
+        # the copy would happen when calling Integer.parse/1.
+        { floatify(int, float, decimal), << ?e, after_e :: binary >> }
+      { exponential, after_exponential } ->
+        { floatify(int, float, decimal, exponential), after_exponential }
+    end
+  end
+
+  defp parse(bitstring, float, decimal, int) do
+    { floatify(int, float, decimal), bitstring }
+  end
+
+  defp floatify(int, float, decimal, exponential // 0) do
+    multiplier = if int < 0, do: -1.0, else: 1.0
+
+    # Try to ensure the minimum amount of rounding errors
+    result = multiplier * (abs(int) * :math.pow(10, decimal) + float) * :math.pow(10, exponential - decimal)
+
+    # Try avoiding stuff like this:
+    # iex(1)> 0.0001 * 75
+    # 0.007500000000000001
+    # Due to IEEE 754 floating point standard
+    # http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
+
+    final_decimal_places = decimal - exponential
+    if final_decimal_places > 0 do
+      decimal_power_round = :math.pow(10,  final_decimal_places)
+      trunc(result * decimal_power_round) / decimal_power_round
+    else
+      result
+    end
+  end
+end
@@ -60,7 +60,7 @@ defmodule GenFSM.Behaviour do
          end

          def short_paid(:coin, state_data) do
-            { :next_state, :paid_in_full, state_data.update_coins(&1 + 1) }
+            { :next_state, :paid_in_full, &state_data.update_coins(&1 + 1) }
          end

          def short_paid(:request_coffee, state_data) do
@@ -84,7 +84,7 @@ defmodule GenFSM.Behaviour do


          def paid_in_full(:coin, state_data) do
-            { :next_state, :paid_in_full, state_data.update_coins(&1 + 1) }
+            { :next_state, :paid_in_full, &state_data.update_coins(&1 + 1) }
          end

          def paid_in_full(:request_coffee, _state_data) do
@@ -186,7 +186,7 @@ defmodule GenFSM.Behaviour do

      @doc false
      def handle_sync_event(_event, from, state_name, state_data) do
-        { :reply, :default_implementation, state_name, state_data }
+        { :reply, :ok, state_name, state_data }
      end

      @doc false
@@ -107,12 +107,6 @@ defmodule HashDict do
    dict
  end

-  @doc false
-  def update(dict, key, fun) when is_function(fun, 1) do
-    IO.write "HashDict.update/3 is deprecated, please use HashDict.update!/3 instead\n#{Exception.format_stacktrace}"
-    update!(dict, key, fun)
-  end
-
  def update!(dict, key, fun) when is_function(fun, 1) do
    case dict_put(dict, key, { :update, nil, fun }) do
      { dict, 0 } ->
@@ -159,13 +153,13 @@ defmodule HashDict do

  def merge(dict1, dict2, callback) when is_record(dict1, HashDict) and is_record(dict2, HashDict) and elem(dict1, 1) < elem(dict2, 1) do
    dict_fold dict1, dict2, fn [k|v1], acc ->
-      update(acc, k, v1, callback.(k, v1, &1))
+      update(acc, k, v1, &callback.(k, v1, &1))
    end
  end

  def merge(dict1, dict2, callback) when is_record(dict1, HashDict) and is_record(dict2, HashDict) do
    dict_fold dict2, dict1, fn [k|v2], acc ->
-      update(acc, k, v2, callback.(k, &1, v2))
+      update(acc, k, v2, &callback.(k, &1, v2))
    end
  end

@@ -103,7 +103,7 @@ defmodule HashSet do
  end

  def to_list(set) do
-    set_fold(set, [], [&1|&2]) |> :lists.reverse
+    set_fold(set, [], &[&1|&2]) |> :lists.reverse
  end

  def put(set, member) do
@@ -476,13 +476,6 @@ defmodule HashSet do
  defp each_contract(acc, [m|bucket]), do: [m|each_contract(acc, bucket)]
  defp each_contract([], bucket), do: bucket
  defp each_contract(acc, []), do: acc
-
-  @doc false
-  def inspect_depth(trie(depth: d)), do: d
-  @doc false
-  def inspect_contract(trie(contract_on: c)), do: c
-  @doc false
-  def inspect_expand(trie(expand_on: e)), do: e
 end

 defimpl Enumerable, for: HashSet do
@@ -267,9 +267,9 @@ defimpl Inspect, for: List do
      :io_lib.printable_list(thing) ->
        << ?', Inspect.BitString.escape(String.from_char_list!(thing), ?') :: binary, ?' >>
      keyword?(thing) && not opts.raw ->
-        surround_many("[", thing, "]", opts.limit, keyword(&1, opts))
+        surround_many("[", thing, "]", opts.limit, &keyword(&1, opts))
      true ->
-        surround_many("[", thing, "]", opts.limit, Kernel.inspect(&1, opts))
+        surround_many("[", thing, "]", opts.limit, &Kernel.inspect(&1, opts))
    end
  end

@@ -317,7 +317,7 @@ defimpl Inspect, for: Tuple do
  def inspect(tuple, opts) do
    unless opts.raw do
      record_inspect(tuple, opts)
-    end || surround_many("{", tuple_to_list(tuple), "}", opts.limit, Kernel.inspect(&1, opts))
+    end || surround_many("{", tuple_to_list(tuple), "}", opts.limit, &Kernel.inspect(&1, opts))
  end

  ## Helpers
@@ -331,7 +331,7 @@ defimpl Inspect, for: Tuple do
      else
        surround_record(name, fields, tail, opts)
      end
-    end || surround_many("{", [name|tail], "}", opts.limit, Kernel.inspect(&1, opts))
+    end || surround_many("{", [name|tail], "}", opts.limit, &Kernel.inspect(&1, opts))
  end

  defp record_fields(name) do
@@ -351,22 +351,35 @@ defimpl Inspect, for: Tuple do

    concat(
      Inspect.Atom.inspect(name, opts),
-      surround_many("[", Enum.zip(fields, tail), "]", opts.limit, keyword(&1, opts))
+      surround_many("[", Enum.zip(fields, tail), "]", opts.limit, &keyword(&1, opts))
    )
  end

  defp keyword({ k, v }, opts) do
    concat(
-      atom_to_binary(k, :utf8) <> ": ",
+      atom_to_binary(k) <> ": ",
      Kernel.inspect(v, opts)
    )
  end
 end

-defimpl Inspect, for: Number do
+defimpl Inspect, for: Integer do
  @doc """
-  Represents the number as a string.
+  Represents the integer as a string.

+  ## Examples
+
+      iex> inspect(1)
+      "1"
+
+  """
+  def inspect(thing, _opts) do
+    integer_to_binary(thing)
+  end
+end
+
+defimpl Inspect, for: Float do
+  @doc """
  Floats are represented using the shortened, correctly rounded string
  that converts to float when read back with `binary_to_float/1`. This
  is done via the Erlang implementation of _Printing Floating-Point
@@ -375,14 +388,10 @@ defimpl Inspect, for: Number do

  ## Examples

-      iex> inspect(1)
-      "1"
+      iex> inspect(1.0)
+      "1.0"

  """
-  def inspect(thing, _opts) when is_integer(thing) do
-    integer_to_binary(thing)
-  end
-
  def inspect(thing, _opts) do
    iolist_to_binary(:io_lib_format.fwrite_g(thing))
  end
@@ -446,7 +455,7 @@ end

 defimpl Inspect, for: PID do
  def inspect(pid, _opts) do
-    "#PID" <> iolist_to_binary(pid_to_list(pid))
+    "#PID" <> iolist_to_binary(:erlang.pid_to_list(pid))
  end
 end

@@ -82,6 +82,28 @@ defmodule Inspect.Algebra do
  defrecordp :doc_break, str: " " :: binary
  defrecordp :doc_group, doc: :doc_nil :: t

+  defmacrop is_doc(doc) do
+    if __CALLER__.in_guard? 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
+      unquote(doc) |> is_binary or
+      unquote(doc) |> is_integer or
+      unquote(doc) == :doc_nil or
+      (unquote(doc) |> is_tuple and
+       elem(unquote(doc), 0) in [:doc_cons, :doc_nest, :doc_break, :doc_group])
+    end
+  end
+
  @doc """
  Returns `:doc_nil` which is a document entity used to represent
  nothingness. Takes no arguments.
@@ -107,13 +129,17 @@ defmodule Inspect.Algebra do

  """
  @spec concat(t, t) :: doc_cons_t
-  def concat(x, y), do: doc_cons(left: x, right: y)
+  def concat(x, y) when is_doc(x) and is_doc(y) do
+    doc_cons(left: x, right: y)
+  end

  @doc """
  Concatenates a list of documents.
  """
  @spec concat([t]) :: doc_cons_t
-  def concat(docs), do: folddoc(docs, concat(&1, &2))
+  def concat(docs) do
+    folddoc(docs, &concat(&1, &2))
+  end

  @doc """
  Nests document entity `x` positions deep. Nesting will be
@@ -127,8 +153,13 @@ defmodule Inspect.Algebra do

  """
  @spec nest(t, non_neg_integer) :: doc_nest_t
-  def nest(x, 0),                    do: x
-  def nest(x, i) when is_integer(i), do: doc_nest(indent: i, doc: x)
+  def nest(x, 0) when is_doc(x) do
+    x
+  end
+
+  def nest(x, i) when is_doc(x) and is_integer(i) do
+    doc_nest(indent: i, doc: x)
+  end

  @doc %S"""
  Document entity representing a break. This break can
@@ -198,7 +229,9 @@ defmodule Inspect.Algebra do

  """
  @spec group(t) :: doc_group_t
-  def group(d), do: doc_group(doc: d)
+  def group(d) when is_doc(d) do
+    doc_group(doc: d)
+  end

  @doc """
  Inserts a mandatory single space between two document entities.
@@ -240,7 +273,7 @@ defmodule Inspect.Algebra do
      "A!B"

  """
-  @spec folddoc([any], ((any, [t]) -> t)) :: t
+  @spec folddoc([t], ((t, t) -> t)) :: t
  def folddoc([], _), do: empty
  def folddoc([doc], _), do: doc
  def folddoc([d|ds], f), do: f.(d, folddoc(ds, f))
@@ -273,11 +306,11 @@ defmodule Inspect.Algebra do

  ## Examples

-      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]", :infinity, integer_to_binary(&1))
+      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]", :infinity, &integer_to_binary(&1))
      iex> Inspect.Algebra.pretty(doc, 5)
      "[1,\n 2,\n 3,\n 4,\n 5]"

-      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]", 3, integer_to_binary(&1))
+      iex> doc = Inspect.Algebra.surround_many("[", Enum.to_list(1..5), "]", 3, &integer_to_binary(&1))
      iex> Inspect.Algebra.pretty(doc, 20)
      "[1, 2, 3, ...]"

@@ -357,7 +390,7 @@ defmodule Inspect.Algebra do
  def fits?(w, [{i, _, doc_group(doc: x)} | t]),            do: fits?(w, [{i, :flat, x} | t])

  @doc false
-  @spec format(integer, integer, [{ integer, mode, t }]) :: atom | tuple
+  @spec format(integer | :infinity, integer, [{ integer, mode, t }]) :: atom | tuple
  def format(_, _, []),                                        do: :s_nil
  def format(w, k, [{_, _, :doc_nil} | t]),                    do: format(w, k, t)
  def format(w, k, [{i, m, doc_cons(left: x, right: y)} | t]), do: format(w, k, [{i, m, x} | [{i, m, y} | t]])
@@ -367,7 +400,8 @@ defmodule Inspect.Algebra do
  def format(w, k, [{_, :flat, doc_break(str: s)} | t]),       do: s_text(str: s, sdoc: format(w, (k + byte_size s), t))
  def format(w, k, [{i, :break, doc_break(str: s)} | t]) do
    k = k + byte_size(s)
-    if fits?(w - k, t) do
+
+    if w == :infinity or fits?(w - k, t) do
      s_text(str: s, sdoc: format(w, k, t))
    else
      s_line(indent: i, sdoc: format(w, i, t))
@@ -3,17 +3,68 @@ defmodule Integer do
  Functions for working with integers.
  """

+  import Bitwise
+
  @doc """
-  Returns true if `n` is an odd number, otherwise false.
+  Determines if an integer is odd.
+
+  Returns `true` if `n` is an odd number, otherwise `false`.
+  Implemented as a macro so it is allowed in guard clauses.
  """
  defmacro odd?(n) do
-    quote do: rem(unquote(n), 2) != 0
+    quote do: (unquote(n) &&& 1) == 1
  end

  @doc """
-  Returns true if `n` is an even number, otherwise false.
+  Determines if an integer is even.
+
+  Returns `true` if `n` is an even number, otherwise `false`.
+  Implemented as a macro so it is allowed in guard clauses.
  """
  defmacro even?(n) do
-    quote do: rem(unquote(n), 2) == 0
+    quote do: (unquote(n) &&& 1) == 0
+  end
+
+  @doc """
+  Converts a binary to an integer. 
+  
+  If successful, returns a tuple of the form `{ integer, remainder_of_binary }`.
+  Otherwise `:error`.
+
+  ## Examples
+
+      iex> Integer.parse("34")
+      {34,""}
+      iex> Integer.parse("34.5")
+      {34,".5"}
+      iex> Integer.parse("three")
+      :error
+
+  """
+  @spec parse(binary) :: { integer, binary } | :error
+  def parse(<< ?-, bin :: binary >>) do
+    case do_parse(bin) do
+      :error -> :error
+      { number, remainder } -> { -number, remainder }
+    end
+  end
+
+  def parse(<< ?+, bin :: binary >>) do
+    do_parse(bin)
+  end
+
+  def parse(bin) when is_binary(bin) do
+    do_parse(bin)
+  end
+
+  defp do_parse(<< char, bin :: binary >>) when char in ?0..?9, do: do_parse(bin, char - ?0)
+  defp do_parse(_), do: :error
+
+  defp do_parse(<< char, rest :: binary >>, acc) when char in ?0..?9 do
+    do_parse rest, 10 * acc + (char - ?0)
+  end
+
+  defp do_parse(bitstring, acc) do
+    { acc, bitstring }
  end
 end
@@ -1,28 +1,32 @@
+defexception IO.StreamError, reason: nil do
+  def message(exception) do
+    formatted = iolist_to_binary(:file.format_error(reason exception))
+    "error during streaming: #{formatted}"
+  end
+end
+
 defmodule IO do
  @moduledoc """
-  Module responsible for doing IO. Many functions in this
-  module expects an IO device and an io data encoded in UTF-8.
+  Functions handling IO.

+  Many functions in this module expects an IO device as 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`.

-  An io data can be:
+  The majority of the functions expect data encoded in UTF-8
+  and will do a conversion to string, via the `String.Chars`
+  protocol (as shown in typespecs).

-  * 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_string` is invoked on the
-    given argument;
+  The functions starting with `bin*` expects iodata as arguments,
+  i.e. iolists or binaries with no particular encoding.

  """

+  @type device   :: atom | pid
+  @type chardata :: char_list | String.Chars.t
+  @type nodata :: { :error, term } | :eof
+
  import :erlang, only: [group_leader: 0]

  defmacrop is_iolist(data) do
@@ -43,6 +47,7 @@ defmodule IO do
    for instance `{:error, :estale}` if reading from an
    NFS file system.
  """
+  @spec read(device, :line | non_neg_integer) :: chardata | nodata
  def read(device // group_leader, chars_or_line)

  def read(device, :line) do
@@ -65,6 +70,7 @@ defmodule IO do
    for instance `{:error, :estale}` if reading from an
    NFS file system.
  """
+  @spec binread(device, :line | non_neg_integer) :: iodata | nodata
  def binread(device // group_leader, chars_or_line)

  def binread(device, :line) do
@@ -98,8 +104,9 @@ defmodule IO do
      #=> "error"

  """
-  def write(device // group_leader(), item) when is_iolist(item) do
-    :io.put_chars map_dev(device), item
+  @spec write(device, chardata) :: :ok
+  def write(device // group_leader(), item) do
+    :io.put_chars map_dev(device), to_chardata(item)
  end

  @doc """
@@ -108,6 +115,7 @@ defmodule IO do

  Check `write/2` for more information.
  """
+  @spec binwrite(device, iodata) :: :ok | { :error, term }
  def binwrite(device // group_leader(), item) when is_iolist(item) do
    :file.write map_dev(device), item
  end
@@ -117,9 +125,10 @@ defmodule IO do
  but adds a newline at the end. The argument is expected
  to be a chardata.
  """
-  def puts(device // group_leader(), item) when is_iolist(item) do
+  @spec puts(device, chardata) :: :ok
+  def puts(device // group_leader(), item) do
    erl_dev = map_dev(device)
-    :io.put_chars erl_dev, [item, ?\n]
+    :io.put_chars erl_dev, [to_chardata(item), ?\n]
  end

  @doc """
@@ -135,6 +144,7 @@ defmodule IO do
      IO.inspect Process.list

  """
+  @spec inspect(term, Keyword.t) :: term
  def inspect(item, opts // []) do
    inspect group_leader(), item, opts
  end
@@ -142,6 +152,7 @@ defmodule IO do
  @doc """
  Inspects the item with options using the given device.
  """
+  @spec inspect(device, term, Keyword.t) :: term
  def inspect(device, item, opts) when is_list(opts) do
    opts = Keyword.put_new(opts, :pretty, true)

@@ -160,7 +171,7 @@ defmodule IO do
  Gets a number of bytes from the io device. 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. 
+  Otherwise, `count` is the number of raw bytes to be retrieved.
  It returns:

  * `data` - The input characters.
@@ -171,6 +182,8 @@ defmodule IO do
    for instance `{:error, :estale}` if reading from an
    NFS file system.
  """
+  @spec getn(chardata, pos_integer) :: chardata | nodata
+  @spec getn(device, chardata) :: chardata | nodata
  def getn(prompt, count // 1)

  def getn(prompt, count) when is_integer(count) do
@@ -187,8 +200,9 @@ defmodule IO do
  the number of unicode codepoints to be retrieved.
  Otherwise, `count` is the number of raw bytes to be retrieved.
  """
+  @spec getn(device, chardata, pos_integer) :: chardata | nodata
  def getn(device, prompt, count) do
-    :io.get_chars(map_dev(device), prompt, count)
+    :io.get_chars(map_dev(device), to_chardata(prompt), count)
  end

  @doc """
@@ -203,50 +217,46 @@ defmodule IO do
    for instance `{:error, :estale}` if reading from an
    NFS file system.
  """
+  @spec gets(device, chardata) :: chardata | nodata
  def gets(device // group_leader(), prompt) do
-    :io.get_line(map_dev(device), prompt)
+    :io.get_line(map_dev(device), to_chardata(prompt))
  end

  @doc """
  Converts the io device into a Stream. The device is
-  iterated line by line if :line is given or by a given
+  iterated line by line if `:line` is given or by a given
  number of codepoints.

-  This reads the io as utf-8. Check out
+  This reads 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)
+      Enum.each IO.stream(:stdio, :line), &IO.write(&1)

  """
-  def stream(device, line_or_bytes) do
-    stream(map_dev(device), line_or_bytes, &1, &2)
-  end
-
-  @doc false
-  def stream(device) do
-    IO.write "IO.stream(device) is deprecated, please use IO.stream(device, :line) instead\n#{Exception.format_stacktrace}"
-    stream(device, :line)
+  @spec stream(device, :line | pos_integer) :: Enumerable.t
+  def stream(device, line_or_codepoints) do
+    fn(acc, f) -> stream(map_dev(device), line_or_codepoints, acc, f) end
  end

  @doc """
  Converts the io device into a Stream. The device is
-  iterated line by line.
+  iterated line by line or by a number of bytes. This
+  reads the IO as a raw binary.

-  This reads 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.
  """
+  @spec binstream(device, :line | pos_integer) :: Enumerable.t
  def binstream(device, line_or_bytes) do
-    binstream(map_dev(device), line_or_bytes, &1, &2)
-  end
-
-  @doc false
-  def binstream(device) do
-    IO.write "IO.binstream(device) is deprecated, please use IO.binstream(device, :line) instead\n#{Exception.format_stacktrace}"
-    binstream(device, :line)
+    fn(acc, f) -> binstream(map_dev(device), line_or_bytes, acc, f) end
  end

  @doc false
@@ -255,7 +265,7 @@ defmodule IO do
      :eof ->
        acc
      { :error, reason } ->
-        raise File.IteratorError, reason: reason
+        raise IO.StreamError, reason: reason
      data ->
        stream(device, what, fun.(data, acc), fun)
    end
@@ -267,7 +277,7 @@ defmodule IO do
      :eof ->
        acc
      { :error, reason } ->
-        raise File.IteratorError, reason: reason
+        raise IO.StreamError, reason: reason
      data ->
        binstream(device, what, fun.(data, acc), fun)
    end
@@ -277,4 +287,7 @@ defmodule IO do
  defp map_dev(:stdio),  do: :standard_io
  defp map_dev(:stderr), do: :standard_error
  defp map_dev(other),   do: other
+
+  defp to_chardata(list) when is_list(list), do: list
+  defp to_chardata(other), do: to_string(other)
 end
@@ -16,9 +16,9 @@ end

 defmodule IO.ANSI do
  @moduledoc """
-  This module provides functionality to render ANSI escape sequences
+  Functionality to render ANSI escape sequences
  (http://en.wikipedia.org/wiki/ANSI_escape_code) —  characters embedded
-  in the text used to control formatting, color, and other output options
+  in text used to control formatting, color, and other output options
  on video text terminals.
  """

@@ -28,7 +28,7 @@ defmodule IO.ANSI do
  Checks whether the default I/O device is a terminal or a file.

  Used to identify whether printing ANSI escape sequences will likely
-  be printed as intended.
+  be displayed as intended.
  """
  @spec terminal? :: boolean
  @spec terminal?(:io.device) :: boolean
@@ -144,18 +144,19 @@ defmodule IO.ANSI do
  The format for referring to sequences is `%{red}` and `%{red,bright}` (for
  multiple sequences).

-  It will also append a %{reset} to the string. If you don't want this
-  behaviour, use `escape_fragment/1` and `escape_fragment/2`.
+  It will also append a `%{reset}` to the string. If you don't want this
+  behaviour, use `escape_fragment/2`.

  An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When false, no ANSI codes will emitted.
+  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
  By default, standard output will be checked if it is a terminal capable
-  of handling these sequences (using `terminal?/0` function)
+  of handling these sequences (using `terminal?/1` function)

-  ## Example
+  ## Examples
+
+      iex> IO.ANSI.escape("Hello %{red,bright,green}yes", true)
+      "Hello \e[31m\e[1m\e[32myes\e[0m"

-    iex> IO.ANSI.escape("Hello %{red,bright,green}yes", true)
-    "Hello \e[31m\e[1m\e[32myes\e[0m"
  """
  @spec escape(String.t, emit :: boolean) :: String.t
  def escape(string, emit // terminal?) do
@@ -174,16 +175,16 @@ defmodule IO.ANSI do
  multiple sequences).

  An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When false, no ANSI codes will emitted.
+  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
  By default, standard output will be checked if it is a terminal capable
-  of handling these sequences (using `terminal?/0` function)
+  of handling these sequences (using `terminal?/1` function)

-  ## Example
+  ## Examples

-    iex> IO.ANSI.escape_fragment("Hello %{red,bright,green}yes", true)
-    "Hello \e[31m\e[1m\e[32myes"
-    iex> IO.ANSI.escape_fragment("%{reset}bye", true)
-    "\e[0mbye"
+      iex> IO.ANSI.escape_fragment("Hello %{red,bright,green}yes", true)
+      "Hello \e[31m\e[1m\e[32myes"
+      iex> IO.ANSI.escape_fragment("%{reset}bye", true)
+      "\e[0mbye"

  """
  @spec escape_fragment(String.t, emit :: boolean) :: String.t
@@ -15,12 +15,12 @@ defmodule Kernel.CLI do
    System.argv(argv)

    run fn ->
-      command_results = Enum.map(Enum.reverse(config.commands), process_command(&1, config))
+      command_results = Enum.map(Enum.reverse(config.commands), &process_command(&1, config))
      command_errors  = lc { :error, msg } inlist command_results, do: msg
      errors          = Enum.reverse(config.errors) ++ command_errors

      if errors != [] do
-        Enum.each(errors, IO.puts(:stderr, &1))
+        Enum.each(errors, &IO.puts(:stderr, &1))
        System.halt(1)
      end
    end, config.halt
@@ -77,7 +77,7 @@ defmodule Kernel.CLI do
  defp shared_option?(list, config, callback) do
    case process_shared(list, config) do
      { [h|hs], _ } when h == hd(list) ->
-        new_config = config.update_errors ["#{h} : Unknown option" | &1]
+        new_config = config.update_errors &["#{h} : Unknown option" | &1]
        callback.(hs, new_config)
      { new_list, new_config } ->
        callback.(new_list, new_config)
@@ -104,6 +104,10 @@ defmodule Kernel.CLI do
    prune_stacktrace(t)
  end

+  defp prune_stacktrace([{ __MODULE__, :wrapper, 1, _ }|_]) do
+    []
+  end
+
  defp prune_stacktrace([h|t]) do
    [h|prune_stacktrace(t)]
  end
@@ -120,17 +124,17 @@ defmodule Kernel.CLI do
  end

  defp process_shared(["-pa", h|t], config) do
-    Enum.each Path.wildcard(Path.expand(h)), Code.prepend_path(&1)
+    Enum.each Path.wildcard(Path.expand(h)), &Code.prepend_path(&1)
    process_shared t, config
  end

  defp process_shared(["-pz", h|t], config) do
-    Enum.each Path.wildcard(Path.expand(h)), Code.append_path(&1)
+    Enum.each Path.wildcard(Path.expand(h)), &Code.append_path(&1)
    process_shared t, config
  end

  defp process_shared(["--app", h|t], config) do
-    process_shared t, config.update_commands [{:app, h}|&1]
+    process_shared t, config.update_commands &[{:app, h}|&1]
  end

  defp process_shared(["--no-halt"|t], config) do
@@ -138,15 +142,15 @@ defmodule Kernel.CLI do
  end

  defp process_shared(["-e", h|t], config) do
-    process_shared t, config.update_commands [{:eval, h}|&1]
+    process_shared t, config.update_commands &[{:eval, h}|&1]
  end

  defp process_shared(["-r", h|t], config) do
-    process_shared t, config.update_commands [{:require, h}|&1]
+    process_shared t, config.update_commands &[{:require, h}|&1]
  end

  defp process_shared(["-pr", h|t], config) do
-    process_shared t, config.update_commands [{:parallel_require, h}|&1]
+    process_shared t, config.update_commands &[{:parallel_require, h}|&1]
  end

  defp process_shared([erl, _|t], config) when erl in ["--erl", "--sname", "--name", "--cookie"] do
@@ -176,15 +180,15 @@ defmodule Kernel.CLI do
  end

  defp process_argv(["-S", h|t], config) do
-    { config.update_commands([{:script, h}|&1]), t }
+    { config.update_commands(&[{:script, h}|&1]), t }
  end

  defp process_argv([h|t] = list, config) do
    case h do
      "-" <> _ ->
-        shared_option? list, config, process_argv(&1, &2)
+        shared_option? list, config, &process_argv(&1, &2)
      _ ->
-        { config.update_commands([{:file, h}|&1]), t }
+        { config.update_commands(&[{:file, h}|&1]), t }
    end
  end

@@ -203,19 +207,19 @@ defmodule Kernel.CLI do
  end

  defp process_compiler(["--no-docs"|t], config) do
-    process_compiler t, config.update_compiler_options([{:docs, false}|&1])
+    process_compiler t, config.update_compiler_options(&[{:docs, false}|&1])
  end

  defp process_compiler(["--no-debug-info"|t], config) do
-    process_compiler t, config.update_compiler_options([{:debug_info, false}|&1])
+    process_compiler t, config.update_compiler_options(&[{:debug_info, false}|&1])
  end

  defp process_compiler(["--ignore-module-conflict"|t], config) do
-    process_compiler t, config.update_compiler_options([{:ignore_module_conflict, true}|&1])
+    process_compiler t, config.update_compiler_options(&[{:ignore_module_conflict, true}|&1])
  end

  defp process_compiler(["--warnings-as-errors"|t], config) do
-    process_compiler t, config.update_compiler_options([{:warnings_as_errors, true}|&1])
+    process_compiler t, config.update_compiler_options(&[{:warnings_as_errors, true}|&1])
  end
  
  defp process_compiler(["--verbose"|t], config) do
@@ -225,15 +229,15 @@ defmodule Kernel.CLI do
  defp process_compiler([h|t] = list, config) do
    case h do
      "-" <> _ ->
-        shared_option? list, config, process_compiler(&1, &2)
+        shared_option? list, config, &process_compiler(&1, &2)
      _ ->
        pattern = if :filelib.is_dir(h), do: "#{h}/**/*.ex", else: h
-        process_compiler t, config.update_compile [pattern|&1]
+        process_compiler t, config.update_compile &[pattern|&1]
    end
  end

  defp process_compiler([], config) do
-    { config.update_commands([{:compile, config.compile}|&1]), [] }
+    { config.update_commands(&[{:compile, config.compile}|&1]), [] }
  end

  # Process iex options
@@ -253,15 +257,15 @@ defmodule Kernel.CLI do
  end

  defp process_iex(["-S", h|t], config) do
-    { config.update_commands([{:script, h}|&1]), t }
+    { config.update_commands(&[{:script, h}|&1]), t }
  end

  defp process_iex([h|t] = list, config) do
    case h do
      "-" <> _ ->
-        shared_option? list, config, process_iex(&1, &2)
+        shared_option? list, config, &process_iex(&1, &2)
      _ ->
-        { config.update_commands([{:file, h}|&1]), t }
+        { config.update_commands(&[{:file, h}|&1]), t }
    end
  end

@@ -273,16 +277,14 @@ defmodule Kernel.CLI do

  defp process_command({:cookie, h}, _config) do
    if Node.alive? do
-      Node.set_cookie(binary_to_atom(h))
-      :ok
+      wrapper fn -> Node.set_cookie(binary_to_atom(h)) end
    else
      { :error, "--cookie : Cannot set cookie if the node is not alive (set --name or --sname)" }
    end
  end

  defp process_command({:eval, expr}, _config) when is_binary(expr) do
-    Code.eval_string(expr, [])
-    :ok
+    wrapper fn -> Code.eval_string(expr, []) end
  end

  defp process_command({:app, app}, _config) when is_binary(app) do
@@ -296,8 +298,7 @@ defmodule Kernel.CLI do

  defp process_command({:script, file}, _config) when is_binary(file) do
    if exec = find_elixir_executable(file) do
-      Code.require_file(exec)
-      :ok
+      wrapper fn -> Code.require_file(exec) end
    else
      { :error, "-S : Could not find executable #{file}" }
    end
@@ -305,8 +306,7 @@ defmodule Kernel.CLI do

  defp process_command({:file, file}, _config) when is_binary(file) do
    if :filelib.is_regular(file) do
-      Code.require_file(file)
-      :ok
+      wrapper fn -> Code.require_file(file) end
    else
      { :error, "No file named #{file}" }
    end
@@ -315,11 +315,10 @@ defmodule Kernel.CLI do
  defp process_command({:require, pattern}, _config) when is_binary(pattern) do
    files = Path.wildcard(pattern)
    files = Enum.uniq(files)
-    files = Enum.filter files, :filelib.is_regular(&1)
+    files = Enum.filter files, &:filelib.is_regular(&1)

    if files != [] do
-      Enum.map files, Code.require_file(&1)
-      :ok
+      wrapper fn -> Enum.map files, &Code.require_file(&1) end
    else
      { :error, "-r : No files matched pattern #{pattern}" }
    end
@@ -328,11 +327,10 @@ defmodule Kernel.CLI do
  defp process_command({:parallel_require, pattern}, _config) when is_binary(pattern) do
    files = Path.wildcard(pattern)
    files = Enum.uniq(files)
-    files = Enum.filter files, :filelib.is_regular(&1)
+    files = Enum.filter files, &:filelib.is_regular(&1)

    if files != [] do
-      Kernel.ParallelRequire.files(files)
-      :ok
+      wrapper fn -> Kernel.ParallelRequire.files(files) end
    else
      { :error, "-pr : No files matched pattern #{pattern}" }
    end
@@ -341,20 +339,26 @@ defmodule Kernel.CLI do
  defp process_command({:compile, patterns}, config) do
    :filelib.ensure_dir(:filename.join(config.output, "."))

-    files = Enum.map patterns, Path.wildcard(&1)
+    files = Enum.map patterns, &Path.wildcard(&1)
    files = Enum.uniq(Enum.concat(files))
-    files = Enum.filter files, :filelib.is_regular(&1)
+    files = Enum.filter files, &:filelib.is_regular(&1)

    if files != [] do
-      Code.compiler_options(config.compiler_options)
-      Kernel.ParallelCompiler.files_to_path(files, config.output,
-        each_file: fn file -> if config.verbose_compile do IO.puts "Compiled #{file}" end end)
-      :ok
+      wrapper fn ->
+        Code.compiler_options(config.compiler_options)
+        Kernel.ParallelCompiler.files_to_path(files, config.output,
+          each_file: fn file -> if config.verbose_compile do IO.puts "Compiled #{file}" end end)
+      end
    else
      { :error, "--compile : No files matched patterns #{Enum.join(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
@@ -0,0 +1,175 @@
+# This is a module Elixir responsible for tracking
+# the usage of aliases, imports and requires in the Elixir scope.
+#
+# The implementation simply stores dispatch information in an
+# ETS table and then consults this table once compilation is done.
+#
+# Note that since this is required for bootstrap, we can't use
+# any of the `GenServer.Behaviour` conveniences.
+defmodule Kernel.LexicalTracker do
+  @timeout  30_000
+  @behavior :gen_server
+
+  @import 2
+  @alias  3
+
+  @doc """
+  Returns all remotes linked to in this lexical scope.
+  """
+  def remotes(arg) do
+    # If the module is compiled from a function, its lexical
+    # scope may be long gone, so it has no associated PID.
+    if pid = to_pid(arg) do
+      ets = :gen_server.call(pid, :ets, @timeout)
+      :ets.match(ets, { :"$1", :_, :_ }) |> List.flatten
+    else
+      []
+    end
+  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, :__lexical_tracker)
+    val
+  end
+
+  # Internal API
+
+  # Starts the tracker and returns its pid.
+  @doc false
+  def start_link do
+    { :ok, pid } = :gen_server.start_link(__MODULE__, [], [])
+    pid
+  end
+
+  @doc false
+  def stop(pid) do
+    :gen_server.cast(pid, :stop)
+  end
+
+  @doc false
+  def add_import(pid, module, line, warn) do
+    :gen_server.cast(pid, { :add_import, module, line, warn })
+  end
+
+  @doc false
+  def add_alias(pid, module, line, warn) do
+    :gen_server.cast(pid, { :add_alias, module, line, warn })
+  end
+
+  @doc false
+  def remote_dispatch(pid, module) do
+    :gen_server.cast(pid, { :remote_dispatch, module })
+  end
+
+  @doc false
+  def import_dispatch(pid, module) do
+    :gen_server.cast(pid, { :import_dispatch, module })
+  end
+
+  @doc false
+  def alias_dispatch(pid, 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, pos) do
+    ets = :gen_server.call(pid, :ets, @timeout)
+    :ets.foldl(fn
+      { module, _, _ } = tuple, acc when is_integer(:erlang.element(pos, tuple)) ->
+        [{ module, :erlang.element(pos, tuple) }|acc]
+      _, acc ->
+        acc
+    end, [], ets) |> Enum.sort
+  end
+
+  # Callbacks
+
+
+  def init([]) do
+    { :ok, :ets.new(:lexical, [:protected]) }
+  end
+
+  def handle_call(:ets, _from, d) do
+    { :reply, d, d }
+  end
+
+  def handle_call(_request, _from, d) do
+    { :noreply, d }
+  end
+
+  def handle_cast({ :remote_dispatch, module }, d) do
+    add_module(d, module)
+    { :noreply, d }
+  end
+
+  def handle_cast({ :import_dispatch, module }, d) do
+    add_dispatch(d, module, @import)
+    { :noreply, d }
+  end
+
+  def handle_cast({ :alias_dispatch, module }, d) do
+    add_dispatch(d, module, @alias)
+    { :noreply, d }
+  end
+
+  def handle_cast({ :add_import, module, line, warn }, d) do
+    add_directive(d, module, line, warn, @import)
+    { :noreply, d }
+  end
+
+  def handle_cast({ :add_alias, module, line, warn }, d) do
+    add_directive(d, module, line, warn, @alias)
+    { :noreply, d }
+  end
+
+  def handle_cast(:stop, d) do
+    { :stop, :normal, d }
+  end
+
+  def handle_cast(_msg, d) do
+    { :noreply, d }
+  end
+
+  def handle_info(_msg, d) do
+    { :noreply, d }
+  end
+
+  def terminate(_reason, _d) do
+    :ok
+  end
+
+  def code_change(_old, d, _extra) do
+    { :ok, d }
+  end
+
+  # Callbacks helpers
+
+  # In the table we keep imports and aliases.
+  # If the value is false, it was not imported/aliased
+  # If the value is true, it was imported/aliased
+  # If the value is a line, it was imported/aliased and has a pending warning
+  defp add_module(d, module) do
+    :ets.insert_new(d, { module, false, false })
+  end
+
+  defp add_dispatch(d, module, pos) do
+    :ets.update_element(d, module, { pos, true })
+  end
+
+  defp add_directive(d, module, line, warn, pos) do
+    add_module(d, module)
+    marker = if warn, do: line, else: true
+    :ets.update_element(d, module, { pos, marker })
+  end
+end
@@ -20,13 +20,8 @@ defmodule Kernel.ParallelCompiler do
  * `:each_file` - for each file compiled, invokes the callback passing the file
  * `:each_module` - for each module compiled, invokes the callback
                     passing the file, module and the module bytecode
-  * `:each_waiting` - every time a module waits for another module to be compiled,
-                      this callback is invoked with the module we are waiting
-
-  The compiler doesn't care about the return values of the callbacks except
-  by `each_waiting`, which must return nil or a file as a hint where the source
-  could be found.

+  The compiler doesn't care about the return values of the callbacks.
  Returns the modules generated by each compiled file.
  """
  def files(files, callbacks // [])
@@ -47,14 +42,15 @@ defmodule Kernel.ParallelCompiler do

  defp spawn_compilers(files, path, callbacks) do
    Code.ensure_loaded(Kernel.ErrorHandler)
-    :elixir_code_server.cast(:reset_warnings)
+    compiler_pid = self()
+    :elixir_code_server.cast({ :reset_warnings, compiler_pid })
    schedulers = max(:erlang.system_info(:schedulers_online), 2)

    result = spawn_compilers(files, files, path, callbacks, [], [], schedulers, [])

    # In case --warning-as-errors is enabled and there was a warning,
-    # compilation status will be set to error and we fail with Kernel.CompilationError
-    case :elixir_code_server.call(:compilation_status) do
+    # compilation status will be set to error and we fail with CompileError
+    case :elixir_code_server.call({ :compilation_status, compiler_pid }) do
      :ok    -> result
      :error -> raise CompileError, [], []
    end
@@ -118,27 +114,18 @@ defmodule Kernel.ParallelCompiler do
        # list because someone invoked try/rescue UndefinedFunctionError
        new_waiting = List.keydelete(waiting, child, 0)
        spawn_compilers(files, original, output, callbacks, new_waiting, new_queued, schedulers, result)
-      { :module_available, child, file, module, binary } ->
+      { :module_available, child, ref, file, module, binary } ->
        if callback = Keyword.get(callbacks, :each_module) do
          callback.(file, module, binary)
        end

        # Release the module loader which is waiting for an ack
-        child <- { self, :ack }
+        child <- { ref, :ack }

        new_waiting = release_waiting_processes(module, waiting)
        new_result  = [module|result]
        wait_for_messages(files, original, output, callbacks, new_waiting, queued, schedulers, new_result)
      { :waiting, child, on } ->
-        # If one of the callbacks is each_waiting and we haven't seen
-        # the hinted file before, add it to the list to be processed.
-        if (callback = Keyword.get(callbacks, :each_waiting)) &&
-           (hint = callback.(on)) &&
-           not(hint in original) do
-          files    = [hint|files]
-          original = [hint|original]
-        end
-
        new_waiting = :orddict.store(child, on, waiting)
        spawn_compilers(files, original, output, callbacks, new_waiting, queued, schedulers, result)
      { :failure, child, kind, reason, stacktrace } ->
@@ -75,7 +75,7 @@ defmodule Kernel.RecordRewriter do
          if :lists.member({ function, length(args) + 1 }, optimizable) do
            case record_field_info(function) do
              { kind, field } ->
-                if index = Enum.find_index(fields, field == &1) do
+                if index = Enum.find_index(fields, &(field == &1)) do
                  optimize_record_accessor_call(line, res, kind, field, index, left, args)
                end
              nil ->
@@ -352,7 +352,7 @@ defmodule Kernel.RecordRewriter do
  end

  defp extract_vars({ :tuple, _, args }, vars) do
-    [Enum.map(args, extract_vars(&1, []))|vars]
+    [Enum.map(args, &extract_vars(&1, []))|vars]
  end

  defp extract_vars(_, vars) do
@@ -9,8 +9,8 @@ defmodule Kernel.SpecialForms do
  to define data structures, respectively tuples, lists and binaries.

  This module also documents Elixir's pseudo variables (`__MODULE__`,
-  `__FILE__`, `__ENV__` and `__CALLER__`). Pseudo variables return
-  information about Elixir's compilation environment and can only
+  `__FILE__`, `__ENV__`, `__DIR__` and `__CALLER__`). Pseudo variables
+  return information about Elixir's compilation environment and can only
  be read, never assigned to.

  Finally, it also documents 3 special forms (`__block__`,
@@ -22,25 +22,20 @@ defmodule Kernel.SpecialForms do
  @doc """
  Defines a new tuple.

+  Only two item tuples are considered literals in Elixir.
+  Therefore all other tuples are represented in the AST
+  as a call to the special form `:{}`.
+
  ## Examples

      iex> { 1, 2, 3 }
      { 1, 2, 3 }
+      iex> quote do: { 1, 2, 3 }
+      { :{}, [], [1,2,3] }

  """
  defmacro :{}.(args)

-  @doc """
-  Defines a new list.
-
-  ## Examples
-
-      iex> [ 1, 2, 3 ]
-      [ 1, 2, 3 ]
-
-  """
-  defmacro :[].(args)
-
  @doc """
  Defines a new bitstring.

@@ -80,12 +75,12 @@ defmodule Kernel.SpecialForms do

      <<102, rest :: binary>>

-  The type can be integer, float, binary, bytes, bitstring,
-  bits, utf8, utf16 or utf32, e.g.:
+  The type can be integer, float, bitstring/bits, binary/bytes,
+  utf8, utf16 or utf32, e.g.:

      <<102 :: float, rest :: binary>>

-  Integer can be any arbitrary precision integer. A float is an
+  An integer can be any arbitrary precision integer. A float is an
  IEEE 754 binary32 or binary64 floating point number. A bitstring
  is an arbitrary series of bits. A binary is a special case of
  bitstring that has a total size divisible by 8.
@@ -179,7 +174,120 @@ defmodule Kernel.SpecialForms do
  defmacro :<<>>.(args)

  @doc """
-  `alias` is used to setup atom aliases, often useful with modules names.
+  Defines a remote call or an alias.
+
+  The dot (`.`) in Elixir can be used for remote calls:
+
+      iex> String.downcase("FOO")
+      "foo"
+
+  In this example above, we have used `.` to invoke `downcase` in the
+  `String` alias, passing "FOO" as argument. We can also use the dot
+  for creating aliases:
+
+      iex> Hello.World
+      Hello.World
+
+  This time, we have joined two aliases, defining the final alias
+  `Hello.World`.
+
+  ## Syntax
+
+  The right side of `.` may be a word starting in upcase, which represents
+  an alias, a word starting with lowercase or underscore, any valid language
+  operator or any name wrapped in single- or double-quotes. Those are all valid
+  examples:
+
+      iex> Kernel.Sample
+      Kernel.Sample
+      iex> Kernel.length([1,2,3])
+      3
+      iex> Kernel.+(1, 2)
+      3
+      iex> Kernel."length"([1,2,3])
+      3
+      iex> Kernel.'+'(1, 2)
+      3
+
+  Note that `Kernel."HELLO"` will be treated as a remote call and not an alias.
+  This choice was done so every time single- or double-quotes are used, we have
+  a remote call irregardless of the quote contents. This decision is also reflected
+  in the quoted expressions discussed below.
+
+  ## Runtime (dynamic) behaviour
+
+  The result returned by `.` is always specified by the right-side:
+
+      iex> x = String
+      iex> x.downcase("FOO")
+      "foo"
+      iex> x.Sample
+      String.Sample
+
+  In case the right-side is also dynamic, `.`'s behaviour can be reproduced
+  at runtime via `apply/3` and `Module.concat/2`:
+
+      iex> apply(Kernel, :+, [1,2])
+      3
+      iex> Module.concat(Kernel, Sample)
+      Kernel.Sample
+
+  ## Quoted expression
+
+  When `.` is used, the quoted expression may take two distinct
+  forms. When the right side starts with a lowercase letter (or
+  underscore):
+
+      iex> quote do: String.downcase("FOO")
+      {{:., [], [{:__aliases__, [alias: false], [:String]}, :downcase]}, [], ["FOO"]}
+
+  Notice we have an inner tuple, containing the atom `:.` representing
+  the dot as first element:
+
+      {:., [], [{:__aliases__, [alias: false], [:String]}, :downcase]}
+
+  This tuple follows the general quoted expression structure in Elixir,
+  with the name as first argument, some keyword list as metadata as second,
+  and the number of arguments as third. In this case, the arguments is the
+  alias `String` and the atom `:downcase`. The second argument is **always**
+  an atom:
+
+      iex> quote do: String."downcase"("FOO")
+      {{:., [], [{:__aliases__, [alias: false], [:String]}, :downcase]}, [], ["FOO"]}
+
+  The tuple containing `:.` is wrapped in another tuple, which actually
+  represents the function call, and has `"FOO"` as argument.
+
+  When the right side is an alias (i.e. starts with uppercase), we get instead:
+
+      iex> quote do: Hello.World
+      {:__aliases__, [alias: false], [:Hello, :World]}
+
+  We got into more details about aliases in the `__aliases__` special form
+  documentation.
+
+  ## Unquoting
+
+  We can also use unquote to generate a remote call in a quoted expression:
+
+      iex> x = :downcase
+      iex> quote do: String.unquote(x)("FOO")
+      {{:., [], [{:__aliases__, [alias: false], [:String]}, :downcase]}, [], ["FOO"]}
+
+  Similar to `Kernel."HELLO"`, `unquote(x)` will always generate a remote call,
+  independent of the value of `x`. To generate an alias via the quoted expression,
+  one needs to rely on `Module.concat/2`:
+
+      iex> x = Sample
+      iex> quote do: Module.concat(String, unquote(x))
+      {{:., [], [{:__aliases__, [alias: false], [:Module]}, :concat]}, [],
+       [{:__aliases__, [alias: false], [:String]}, Sample]}
+
+  """
+  defmacro (:.).(left, right)
+
+  @doc """
+  `alias` is used to setup aliases, often useful with modules names.

  ## Examples

@@ -213,12 +321,23 @@ defmodule Kernel.SpecialForms do
  `import`, `require` and `alias` are called directives and all
  have lexical scope. This means you can set up aliases inside
  specific functions and it won't affect the overall scope.
+
+  ## Warnings
+
+  If you alias a module and you don't use the alias, Elixir is
+  going to issue a warning implying the alias is not being used.
+
+  In case the alias is generated automatically by a macro,
+  Elixir won't emit any warnings though, since the alias
+  was not explicitly defined.
+
+  Both warning behaviors could be changed by explicitily
+  setting the `:warn` option to true or false.
  """
  defmacro alias(module, opts)

  @doc """
-  `require` is used to require the presence of external
-  modules so macros can be invoked.
+  Requires a given module to be compiled and loaded.

  ## Examples

@@ -246,6 +365,8 @@ defmodule Kernel.SpecialForms do
  defmacro require(module, opts)

  @doc """
+  Imports function and macros from other modules.
+
  `import` allows one to easily access functions or macros from
  others modules without using the qualified name.

@@ -335,14 +456,16 @@ defmodule Kernel.SpecialForms do
  defmacro import(module, opts)

  @doc """
-  Returns the current environment information as a `Macro.Env`
-  record. In the environment you can access the current filename,
+  Returns the current environment information as a `Macro.Env[]` record.
+
+  In the environment you can access the current filename,
  line numbers, set up aliases, the current function and others.
  """
  defmacro __ENV__

  @doc """
  Returns the current module name as an atom or `nil` otherwise.
+
  Although the module can be accessed in the `__ENV__`, this macro
  is a convenient shortcut.
  """
@@ -350,6 +473,7 @@ defmodule Kernel.SpecialForms do

  @doc """
  Returns the current file name as a binary.
+
  Although the file can be accessed in the `__ENV__`, this macro
  is a convenient shortcut.
  """
@@ -360,8 +484,8 @@ defmodule Kernel.SpecialForms do
  """
  defmacro __DIR__

-  @doc """
-  Allows you to get the representation of any expression.
+  @doc %S"""
+  Gets the representation of any expression.

  ## Examples

@@ -391,14 +515,14 @@ defmodule Kernel.SpecialForms do
  * `:unquote` - When false, disables unquoting. Useful when you have a quote
                 inside another quote and want to control what quote is
                 able to unquote;
-  * `:location` - When set to `:keep`, keeps the current line and file on quotes.
+  * `:location` - When set to `:keep`, keeps the current line and file from quote.
                  Read the Stacktrace information section below for more information;
  * `:hygiene` - Allows a developer to disable hygiene selectively;
  * `:context` - Sets the resolution context;
-  * `:binding` - Passes a binding to the macro. Whenever a binding is given,
-                 `unquote` is automatically disabled;
+  * `:bind_quoted` - Passes a binding to the macro. Whenever a binding is given,
+                    `unquote` is automatically disabled;

-  ## Macro literals
+  ## Quote literals

  Besides the tuple described above, Elixir has a few literals that
  when quoted return themselves. They are:
@@ -407,40 +531,111 @@ defmodule Kernel.SpecialForms do
      1            #=> Integers
      2.0          #=> Floats
      [1, 2]       #=> Lists
-      "binaries"   #=> Binaries
+      "strings"    #=> Strings
      {key, value} #=> Tuple with two elements

-  ## Hygiene and context
+  ## Quote and macros

-  Elixir macros are hygienic via means of deferred resolution.
-  This means variables, aliases and imports defined inside the
-  quoted refer to the context that defined the macro and not
-  the context where the macro is expanded.
+  `quote` is commonly used with macros for code generation. As an exercise,
+  let's define a macro that multiplies a number by itself (squared). Note
+  there is no reason to define such as a macro (and it would actually be
+  seen as a bad practice), but it is simple enough that allows us to focus
+  on the important aspects of quotes and macros:

-  For this mechanism to work, every quoted code is attached
-  to a context. Consider the following example:
-
-      defmodule ContextSample do
-        def hello do
-          quote do: world
+      defmodule Math do
+        defmacro squared(x) do
+          quote do
+            unquote(x) * unquote(x)
+          end
        end
      end

-      ContextSample.hello
-      #=> {:world,[],ContextSample}
+  We can invoke it as:

-  Notice how the third element of the returned tuple is the
-  module name. This means that the variable is associated to the
-  `ContextSample` module and only code generated by this module
-  will be able to access that particular `world` variable.
-  While this means macros from the same module could have
-  conflicting variables, it also allows different quotes from
-  the same module to access them.
+      import Math
+      IO.puts "Got #{squared(5)}"

-  The context can be disabled or changed by explicitly setting
-  the `context` option. All hygiene mechanisms are based on such
-  context and we are going to explore each of them in the following
-  subsections.
+  At first, there is nothing in this example that actually reveals it is a
+  macro. But what is happening is that, at compilation time, `squared(5)`
+  becomes `5 * 5`. We can see this behaviour in practice though
+  because our macro actually has a bug:
+
+      import Math
+      my_number = fn ->
+        IO.puts "Returning 5"
+        5
+      end
+      IO.puts "Got #{squared(my_number.())}"
+
+  The example above will print:
+
+      Returning 5
+      Returning 5
+      25
+
+  Notice how "Returning 5" was printed twice, instead of just once. This is
+  because a macro receives an expression and not a value (which is what we
+  would expect in a regular function). This means that:
+
+      squared(my_number.())
+
+  Actually expands to:
+
+      my_number.() * my_number.()
+
+  Which invokes the function twice, explaining why we get the printed value
+  twice! In the majority of the cases, this is actually unexpected behaviour,
+  and that's why one of the first things you need to keep in mind when it
+  comes to macros is to **not unquote the same value more than once**.
+
+  Let's fix our macro:
+
+      defmodule Math do
+        defmacro squared(x) do
+          quote do
+            x = unquote(x)
+            x * x
+          end
+        end
+      end
+
+  Now invoking `square(my_number.())` as before will print the value just
+  once.
+
+  In fact, this pattern is so common that most of the times you will want
+  to use the `bind_quoted` option with `quote`:
+
+      defmodule Math do
+        defmacro squared(x) do
+          quote bind_quoted: [x: x] do
+            x * x
+          end
+        end
+      end
+
+  `:bind_quoted` will translate to the same example as above. `:bind_quoted`
+  can be used in many cases and is seen as good practice, not only because
+  it helps us from running into common mistakes but also because it allows
+  us to leverage other tools exposed by macros, as unquote fragments discussed
+  in some sections below.
+
+  Before we finish this brief introduction, you will notice that, even though
+  we defined a variable `x` inside our quote:
+
+      quote do
+        x = unquote(x)
+        x * x
+      end
+
+  When we call:
+
+      import Math
+      squared(5)
+      x #=> ** (RuntimeError) undefined function or variable: x
+
+  We can see that `x` did not leak to the user context. This happens
+  because Elixir macros are hygienic, a topic we will discuss at length
+  in the next sections as well.

  ### Hygiene in variables

@@ -476,31 +671,47 @@ defmodule Kernel.SpecialForms do
      NoHygiene.interference
      a #=> 1

-  It is important to understand that quoted variables are scoped
-  to the module they are defined. That said, even if two modules
-  define the same quoted variable `a`, their values are going
-  to be independent:
+  Note that you cannot even access variables defined by the same
+  module unless you explicitly give it a context:

-      defmodule Hygiene1 do
-        defmacro var1 do
-          quote do: a = 1
+      defmodule Hygiene do
+        defmacro write do
+          quote do
+            a = 1
+          end
+        end
+
+        defmacro read do
+          quote do
+            a
+          end
        end
      end

-      defmodule Hygiene2 do
-        defmacro var2 do
-          quote do: a = 2
+      Hygiene.write
+      Hygiene.read
+      #=> ** (RuntimeError) undefined function or variable: a
+
+  For such, you can explicitly pass the current module scope as
+  argument:
+
+      defmodule ContextHygiene do
+        defmacro write do
+          quote do
+            var!(a, ContextHygiene) = 1
+          end
+        end
+
+        defmacro read do
+          quote do
+            var!(a, ContextHygiene)
+          end
        end
      end

-  Calling macros `var1` and `var2` are not going to change their
-  each other values for `a`. This is useful because quoted
-  variables from different modules cannot conflict. If you desire
-  to explicitly access a variable from another module, we can once
-  again use `var!` macro, but explicitly passing a second argument:
-
-      # Access the variable a from Hygiene1
-      quote do: var!(a, Hygiene1) = 2
+      ContextHygiene.write
+      ContextHygiene.read
+      #=> 1

  Hygiene for variables can be disabled overall as:

@@ -557,7 +768,6 @@ defmodule Kernel.SpecialForms do
        #=> "world"
      end

-
  ## Hygiene in imports

  Similar to aliases, imports in Elixir are hygienic. Consider the
@@ -609,35 +819,35 @@ defmodule Kernel.SpecialForms do

  ## Stacktrace information

-  One of Elixir's goals is to provide a proper stacktrace whenever there is an
-  exception. In order to work properly with macros, the default behavior
-  in quote is to not set a line. When a macro is invoked and the quoted
-  expressions is expanded, the call site line is inserted.
+  When defining functions via macros, developers have the option of
+  choosing if runtime errors will be reported from the caller or from
+  inside the quote. Let's see an example:

-  This is a good behavior for the majority of the cases, except if the macro
-  is defining new functions. Consider this example:
-
-      defmodule MyServer do
-        use GenServer.Behaviour
-      end
-
-  `GenServer.Behaviour` defines new functions in our `MyServer` module.
-  However, if there is an exception in any of these functions, we want
-  the stacktrace to point to the `GenServer.Behaviour` and not the line
-  that calls `use GenServer.Behaviour`. For this reason, there is an
-  option called `:location` that when set to `:keep` keeps the original
-  line and file lines instead of setting them to 0:
-
-      quote location: :keep do
-        def handle_call(request, _from, state) do
-          { :reply, :undef, state }
+      # adder.ex
+      defmodule Adder do
+        @doc "Defines a function that adds two numbers"
+        defmacro defadd do
+          quote location: :keep do
+            def add(a, b), do: a + b
+          end
        end
      end

-  It is important to warn though that `location: :keep` evaluates the
-  code as if it was defined inside `GenServer.Behaviour` file, in
-  particular, the macro `__FILE__` and exceptions happening inside
-  the quote will always point to `GenServer.Behaviour` file.
+      # sample.ex
+      defmodule Sample do
+        import Adder
+        defadd
+      end
+
+  When using `location: :keep` and invalid arguments are given to
+  `Sample.add/2`, the stacktrace information will point to the file
+  and line inside the quote. Without `location: :keep`, the error is
+  reported to where `defadd` was invoked.
+
+  Note that `location: :keep` evaluates the code as if it was defined
+  inside the `Adder` file, in particular, the macro `__FILE__` and
+  exceptions happening inside the quote will always point to the file
+  where `Added` was defined.

  ## Binding and unquote fragments

@@ -697,8 +907,8 @@ defmodule Kernel.SpecialForms do
  One solution for this problem is to disable unquoting in the
  macro, however, doing that would make it impossible to inject
  `kv` representation into the tree. That's when the `:bind_quoted`
-  option comes to the rescue. By using `:bind_quoted`, we can
-  automatically disable unquoting while still injecting the
+  option comes to the rescue (again!). By using `:bind_quoted`, we
+  can automatically disable unquoting while still injecting the
  desired variables into the tree:

      defmacro defkv(kv) do
@@ -709,26 +919,21 @@ defmodule Kernel.SpecialForms do
        end
      end

-  In fact, the `:binding` option is recommended every time one
-  desires to inject a value into the quote.
+  In fact, the `:bind_quoted` option is recommended every time
+  one desires to inject a value into the quote.
  """
  defmacro quote(opts, block)

  @doc """
  When used inside quoting, marks that the variable should
  not be hygienized. The argument can be either a variable
-  node (i.e. a tuple with three elements where the last
-  one is an atom) or an atom representing the variable name.
+  unquoted or an atom representing the variable name.
  Check `quote/2` for more information.
  """
  defmacro var!(var)

  @doc """
  Defines a variable in the given context.
-
-  If the context is `false`, it is not stored in any particular
-  context and the variable is not shared in between clauses.
-
  Check `quote/2` for more information.
  """
  defmacro var!(var, context)
@@ -820,6 +1025,9 @@ defmodule Kernel.SpecialForms do
      iex> lc <<r::8, g::8, b::8>> inbits pixels, do: {r, g, b}
      [{213,45,132},{64,76,32},{76,0,0},{234,32,15}]

+  Variable assignments in the `do` block of the comprehension
+  are not reflected outside of the block.
+
  Note: Unlike Erlang, Elixir comprehension filters
  never behave as guards when it comes to errors. Errors in
  list comprehensions will always be raised. Consider this
@@ -837,10 +1045,11 @@ defmodule Kernel.SpecialForms do
  defmacro lc(args)

  @doc """
-  Defines a bit comprehension. It follows the same syntax as
-  a list comprehension but expects each element returned to
-  be a bitstring. For example, here is how to remove all
-  spaces from a string:
+  Defines a bit comprehension.
+
+  It follows the same syntax and behaviour as a list comprehension
+  but expects each element returned to be a bitstring. For example,
+  here is how to remove all spaces from a string:

      iex> bc <<c>> inbits " hello world ", c != ? , do: <<c>>
      "helloworld"
@@ -849,6 +1058,21 @@ defmodule Kernel.SpecialForms do
  defmacro bc(args)

  @doc """
+  Defines an anonymous function.
+
+  ## Examples
+
+      iex> add = fn a, b -> a + b end
+      iex> add.(1, 2)
+      3
+
+  """
+  name = :fn
+  defmacro unquote(name)(clauses)
+
+  @doc """
+  Internal special form for block expressions.
+
  This is the special form used whenever we have a block
  of expressions in Elixir. This special form is private
  and should not be invoked directly:
@@ -860,7 +1084,7 @@ defmodule Kernel.SpecialForms do
  defmacro __block__(args)

  @doc """
-  Captures a call as an anonymous function.
+  Captures an anonymous function.

  The most common format to capture a function is via module,
  name and arity:
@@ -879,17 +1103,17 @@ defmodule Kernel.SpecialForms do
  A capture also allows the captured functions to be partially
  applied, for example:

-      iex> fun = &atom_to_binary(&1, :utf8)
-      iex> fun.(:hello)
-      "hello"
+      iex> fun = &is_record(&1, Range)
+      iex> fun.(1..3)
+      true

  In the example above, we use &1 as a placeholder, generating
  a function with one argument. We could also use `&2` and `&3`
  to delimit more arguments:

-      iex> fun = &atom_to_binary(&1, &2)
-      iex> fun.(:hello, :utf8)
-      "hello"
+      iex> fun = &is_record(&1, &2)
+      iex> fun.(1..3, Range)
+      true

  Since operators are calls, they are also supported, although
  they require explicit parentheses around:
@@ -938,30 +1162,31 @@ defmodule Kernel.SpecialForms do
  defmacro unquote(name)(expr)

  @doc """
-  This is the special form used whenever we have to temporarily
-  change the scope information of a block. Used when `quote` is
-  invoked with `location: :keep` to execute a given block as if
-  it belonged to another file.
+  Internal special form for modifying scope information.
+
+  Used when `quote` is invoked with `location: :keep` to execute
+  a given block as if it belonged to another file.

      quote location: :keep, do: 1
      #=> { :__scope__, [line: 1], [[file: "iex"],[do: 1]] }

-  Check `quote/1` for more information.
+  Check `quote/2` for more information.
  """
  defmacro __scope__(opts, args)

  @doc """
-  This is the special form used to hold aliases information.
+  Internal special form to hold aliases information.
+
  It is usually compiled to an atom:

-      quote do: Foo.Bar #=>
-      { :__aliases__, [], [:Foo,:Bar] }
+      iex> quote do: Foo.Bar
+      {:__aliases__, [alias: false], [:Foo, :Bar]}

  Elixir represents `Foo.Bar` as `__aliases__` so calls can be
  unambiguously identified by the operator `:.`. For example:

-      quote do: Foo.bar #=>
-      {{:.,[],[{:__aliases__,[],[:Foo]},:bar]},[],[]}
+      iex> quote do: Foo.bar
+      {{:., [], [{:__aliases__, [alias: false], [:Foo]}, :bar]}, [], []}

  Whenever an expression iterator sees a `:.` as the tuple key,
  it can be sure that it represents a call and the second argument
@@ -978,7 +1203,7 @@ defmodule Kernel.SpecialForms do
  4) When the head element of aliases is not an atom, it is expanded at runtime:

        quote do: some_var.Foo
-        {:__aliases__,[],[{:some_var,[],:quoted},:Bar]}
+        {:__aliases__, [], [{:some_var, [], Elixir}, :Foo]}

     Since `some_var` is not available at compilation time, the compiler
     expands such expression to:
@@ -159,7 +159,7 @@ defmodule Kernel.Typespec do
  @doc """
  Defines a `type`, `typep` or `opaque` by receiving Erlang's typespec.
  """
-  def define_type(module, kind, { name, _, vars } = type) when kind in [:type, :typep, :opaque] do
+  def define_type(caller, kind, { name, _, vars } = type) when kind in [:type, :typep, :opaque] do
    { kind, export } =
      case kind do
        :type   -> { :type, true }
@@ -167,12 +167,35 @@ defmodule Kernel.Typespec do
        :opaque -> { :opaque, true }
      end

+    module = caller.module
+    arity  = length(vars)
+
    Module.compile_typespec module, kind, type
-    if export, do:
-      Module.compile_typespec(module, :export_type, [{ name, length(vars) }])
+
+    if export do
+      Module.compile_typespec(module, :export_type, [{ name, arity }])
+    end
+
+    define_doc(caller, kind, name, arity, export)
    type
  end

+  defp define_doc(caller, kind, name, arity, export) do
+    module = caller.module
+    doc    = Module.get_attribute(module, :typedoc)
+
+    if doc do
+      if export do
+        Module.add_doc(module, caller.line, kind, { name, arity }, doc)
+      else
+        :elixir_errors.warn "#{caller.file}:#{caller.line}: type #{name}/#{arity} is private, " <>
+                            "@typedoc's are always discarded for private types\n"
+      end
+    end
+
+    Module.delete_attribute(module, :typedoc)
+  end
+
  @doc """
  Defines a `spec` by receiving Erlang's typespec.
  """
@@ -193,7 +216,7 @@ defmodule Kernel.Typespec do
  for modules being compiled.
  """
  def defines_type?(module, name, arity) do
-    finder = match?({ ^name, _, vars } when length(vars) == arity, &1)
+    finder = &match?({ ^name, _, vars } when length(vars) == arity, &1)
    :lists.any(finder, Module.get_attribute(module, :type)) or
      :lists.any(finder, Module.get_attribute(module, :opaque))
  end
@@ -204,7 +227,7 @@ defmodule Kernel.Typespec do
  """
  def defines_spec?(module, name, arity) do
    tuple = { name, arity }
-    :lists.any(match?(^tuple, &1), Module.get_attribute(module, :spec))
+    :lists.any(&match?(^tuple, &1), Module.get_attribute(module, :spec))
  end

  @doc """
@@ -213,7 +236,7 @@ defmodule Kernel.Typespec do
  """
  def defines_callback?(module, name, arity) do
    tuple = { name, arity }
-    :lists.any(match?(^tuple, &1), Module.get_attribute(module, :callback))
+    :lists.any(&match?(^tuple, &1), Module.get_attribute(module, :callback))
  end

  @doc """
@@ -255,6 +278,26 @@ defmodule Kernel.Typespec do
    quote do: unquote(name)(unquote_splicing(args)) :: unquote(typespec_to_ast(type))
  end

+  @doc """
+  Returns all type docs available from the module's beam code.
+
+  It is returned as a list of tuples where the first element is the pair of type
+  name and arity and the second element is the documentation.
+
+  The module has to have a corresponding beam file on the disk which can be
+  located by the runtime system.
+  """
+  @spec beam_typedocs(module | binary) :: [tuple] | nil
+  def beam_typedocs(module) when is_atom(module) or is_binary(module) do
+    case abstract_code(module) do
+      { :ok, abstract_code } ->
+        type_docs = lc { :attribute, _, :typedoc, tup } inlist abstract_code, do: tup
+        List.flatten(type_docs)
+      _ ->
+        nil
+    end
+  end
+
  @doc """
  Returns all types available from the module's beam code.

@@ -264,7 +307,8 @@ defmodule Kernel.Typespec do
  The module has to have a corresponding beam file on the disk which can be
  located by the runtime system.
  """
-  def beam_types(module) do
+  @spec beam_types(module | binary) :: [tuple] | nil
+  def beam_types(module) when is_atom(module) or is_binary(module) do
    case abstract_code(module) do
      { :ok, abstract_code } ->
        exported_types = lc { :attribute, _, :export_type, types } inlist abstract_code, do: types
@@ -278,7 +322,7 @@ defmodule Kernel.Typespec do
          end
        end
      _ ->
-        []
+        nil
    end
  end

@@ -291,7 +335,8 @@ defmodule Kernel.Typespec do
  The module has to have a corresponding beam file on the disk which can be
  located by the runtime system.
  """
-  def beam_specs(module) do
+  @spec beam_specs(module | binary) :: [tuple] | nil
+  def beam_specs(module) when is_atom(module) or is_binary(module) do
    from_abstract_code(module, :spec)
  end

@@ -301,10 +346,11 @@ defmodule Kernel.Typespec do
  It is returned as a list of tuples where the first
  element is spec name and arity and the second is the spec.

-  The module has to have a corresponding beam file on the disk which can be
-  located by the runtime system.
+  The module has to have a corresponding beam file on the disk
+  which can be located by the runtime system.
  """
-  def beam_callbacks(module) do
+  @spec beam_callbacks(module | binary) :: [tuple] | nil
+  def beam_callbacks(module) when is_atom(module) or is_binary(module) do
    from_abstract_code(module, :callback)
  end

@@ -312,8 +358,8 @@ defmodule Kernel.Typespec do
    case abstract_code(module) do
      { :ok, abstract_code } ->
        lc { :attribute, _, abs_kind, value } inlist abstract_code, kind == abs_kind, do: value
-      _ ->
-        []
+      :error ->
+        nil
    end
  end

@@ -322,7 +368,7 @@ defmodule Kernel.Typespec do
      {:ok, { _, [{ :abstract_code, { _raw_abstract_v1, abstract_code } }] } } ->
        { :ok, abstract_code }
      _ ->
-        []
+        :error
    end
  end

@@ -368,7 +414,7 @@ defmodule Kernel.Typespec do
    vars = lc { :var, _, _ } = var inlist args, do: var
    type = { name, spec, vars }

-    define_type(caller.module, kind, type)
+    define_type(caller, kind, type)
  end

  @doc false
@@ -4,13 +4,23 @@ defmodule Keyword do
  of the tuple is an atom and the second element can be
  any value.

-  A keyword may have duplicated keys, so it is not strictly
+  A keyword may have duplicated keys so it is not strictly
  a dictionary. However most of the functions in this module
-  allows it to behave exactly as a dictionary. For example,
-  `Keyword.get` will get the first entry matching the given
-  key, regardless if duplicated entries exist. Similarly,
-  `Keyword.put` and `Keyword.delete` ensure all duplicated
-  entries for a given key are removed when invoked.
+  behaves exactly as a dictionary and mimic the API defined
+  by the `Dict` behaviour.
+
+  For example, `Keyword.get` will get the first entry matching
+  the given key, regardless if duplicated entries exist.
+  Similarly, `Keyword.put` and `Keyword.delete` ensure all
+  duplicated entries for a given key are removed when invoked.
+  A handful of functions exist to handle duplicated keys, in
+  particular, `from_enum` allows creating a new keywords without
+  removing duplicated keys, `get_values` returns all values for
+  a given key and `delete_first` deletes just one of the existing
+  entries.
+
+  Since a keyword list is simply a list, all the operations defined
+  in `Enum` and `List` can also be applied.
  """

  @type key :: atom
@@ -23,16 +33,12 @@ defmodule Keyword do
  duplicated entries.
  """
  @spec from_enum(Enum.t) :: t
-  def from_enum(enum) when is_list(enum) do
-    enum
-  end
-
  def from_enum(enum) do
-    Enum.map(enum, fn(x) -> x end)
+    Enum.to_list(enum)
  end

  @doc """
-  Checks if the given argument is a keywords list or not
+  Checks if the given argument is a keywords list or not.
  """
  @spec keyword?(term) :: boolean
  def keyword?([{ key, _value } | rest]) when is_atom(key) do
@@ -356,22 +362,16 @@ defmodule Keyword do
    :lists.keymember(key, 1, keywords)
  end

-  @doc false
-  def update(dict, key, fun) when is_function(fun, 1) do
-    IO.write "Keyword.update/3 is deprecated, please use Keyword.update!/3 instead\n#{Exception.format_stacktrace}"
-    update!(dict, key, fun)
-  end
-
  @doc """
  Updates the `key` with the given function. If the `key` does
  not exist, raises `KeyError`.

  ## Examples

-      iex> Keyword.update!([a: 1], :a, &1 * 2)
+      iex> Keyword.update!([a: 1], :a, &(&1 * 2))
      [a: 2]

-      iex> Keyword.update!([a: 1], :b, &1 * 2)
+      iex> Keyword.update!([a: 1], :b, &(&1 * 2))
      ** (KeyError) key not found: :b

  """
@@ -394,10 +394,10 @@ defmodule Keyword do

  ## Examples

-      iex> Keyword.update([a: 1], :a, 13, &1 * 2)
+      iex> Keyword.update([a: 1], :a, 13, &(&1 * 2))
      [a: 2]

-      iex> Keyword.update([a: 1], :b, 11, &1 * 2)
+      iex> Keyword.update([a: 1], :b, 11, &(&1 * 2))
      [a: 1, b: 11]

  """
@@ -413,4 +413,128 @@ defmodule Keyword do
  def update([], key, initial, _fun) when is_atom(key) do
    [{key, initial}]
  end
+
+  @doc """
+  Splits the given keywords in two given the given keys.
+  Duplicated keys are preserved in the split keyword list.
+
+  ## Examples
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4]
+      iex> Keyword.split(d, [:a, :c, :e])
+      { [a: 1, c: 3], [b: 2, d: 4] }
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4, a: 5]
+      iex> Keyword.split(d, [:a, :c, :e])
+      { [a: 1, c: 3, a: 5], [b: 2, d: 4] }
+
+  """
+  def split(dict, keys) do
+    acc = { [], [] }
+
+    { take, drop } = Enum.reduce dict, acc, fn({ k, v }, { take, drop }) ->
+      case :lists.member(k, keys) do
+        true  -> { [{k, v}|take], drop }
+        false -> { take, [{k, v}|drop] }
+      end
+    end
+
+    { Enum.reverse(take), Enum.reverse(drop) }
+  end
+
+  @doc """
+  Takes the given keys from the dict.
+  Duplicated keys are preserved in the new keyword list.
+
+  ## Examples
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4]
+      iex> Keyword.take(d, [:a, :c, :e])
+      [a: 1, c: 3]
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4, a: 5]
+      iex> Keyword.take(d, [:a, :c, :e])
+      [a: 1, c: 3, a: 5]
+
+  """
+  def take(dict, keys) do
+    lc { k, _ } = tuple inlist dict, :lists.member(k, keys), do: tuple
+  end
+
+  @doc """
+  Drops the given keys from the dict.
+  Duplicated keys are preserved in the new keyword list.
+
+  ## Examples
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4]
+      iex> Keyword.drop(d, [:b, :d])
+      [a: 1, c: 3]
+
+      iex> d = [a: 1, b: 2, c: 3, d: 4, a: 5]
+      iex> Keyword.drop(d, [:b, :d])
+      [a: 1, c: 3, a: 5]
+
+  """
+  def drop(dict, keys) do
+    lc { k, _ } = tuple inlist dict, not :lists.member(k, keys), do: tuple
+  end
+
+  @doc """
+  Returns the first value associated with `key` in the keyword
+  list as well as the keyword list without `key`.
+
+  All duplicated entries are removed. See `pop_first/3` for
+  removing only the first entry.
+
+  ## Examples
+
+      iex> Keyword.pop [a: 1], :a
+      {1,[]}
+
+      iex> Keyword.pop [a: 1], :b
+      {nil,[a: 1]}
+
+      iex> Keyword.pop [a: 1], :b, 3
+      {3,[a: 1]}
+
+      iex> Keyword.pop [a: 1], :b, 3
+      {3,[a: 1]}
+
+      iex> Keyword.pop [a: 1, a: 2], :a
+      {1,[]}
+
+  """
+  def pop(dict, key, default // nil) do
+    { get(dict, key, default), delete(dict, key) }
+  end
+
+  @doc """
+  Returns the first value associated with `key` in the keyword
+  list as well as the keyword list without that particular ocurrence
+  of `key`.
+
+  Duplicated entries are not removed.
+
+  ## Examples
+
+      iex> Keyword.pop_first [a: 1], :a
+      {1,[]}
+
+      iex> Keyword.pop_first [a: 1], :b
+      {nil,[a: 1]}
+
+      iex> Keyword.pop_first [a: 1], :b, 3
+      {3,[a: 1]}
+
+      iex> Keyword.pop_first [a: 1], :b, 3
+      {3,[a: 1]}
+
+      iex> Keyword.pop_first [a: 1, a: 2], :a
+      {1,[a: 2]}
+
+  """
+  def pop_first(dict, key, default // nil) do
+    { get(dict, key, default), delete_first(dict, key) }
+  end
 end
@@ -12,18 +12,6 @@ defmodule List do

  @compile :inline_list_funcs

-  @doc false
-  def concat(list) when is_list(list) do
-    IO.write "List.concat/1 is deprecated, please use Enum.concat/1 instead\n#{Exception.format_stacktrace}"
-    :lists.append(list)
-  end
-
-  @doc false
-  def concat(list, elements) when is_list(list) and is_list(elements) do
-    IO.write "List.concat/2 is deprecated, please use Enum.concat/2 instead\n#{Exception.format_stacktrace}"
-    list ++ elements
-  end
-
  @doc """
  Deletes the given item from the list. Returns a list without the item.
  If the item occurs more than once in the list, just the first occurrence
@@ -307,7 +295,7 @@ defmodule List do

  """
  def unzip(list) when is_list(list) do
-    :lists.map tuple_to_list(&1), zip(list)
+    :lists.map &tuple_to_list/1, zip(list)
  end

  @doc """
@@ -9,8 +9,6 @@ defprotocol List.Chars do
  by Kernel invokes this protocol.
  """

-  @only [BitString, List, Atom, Number, Record]
-
  def to_char_list(thing)
 end

@@ -38,13 +36,15 @@ defimpl List.Chars, for: List do
  def to_char_list(list), do: list
 end

-defimpl List.Chars, for: Number do
-  @digits 20
-  @limit  :math.pow(10, @digits)
-
-  def to_char_list(thing) when is_integer(thing) do
+defimpl List.Chars, for: Integer do
+  def to_char_list(thing) do
    integer_to_list(thing)
  end
+end
+
+defimpl List.Chars, for: Float do
+  @digits 20
+  @limit  :math.pow(10, @digits)

  def to_char_list(thing) when thing > @limit do
    float_to_list(thing, scientific: @digits)
@@ -2,6 +2,10 @@ defmodule ListDict do
  @moduledoc """
  A Dict implementation that works on lists of two-items tuples.

+  This dictionary is only recommended for keeping a small amount
+  of values. Other dict alternatives are more viable for keeping
+  any other amount than a handful.
+
  For more information about the functions and their APIs, please
  consult the `Dict` module.
  """
@@ -38,28 +42,25 @@ defmodule ListDict do
    length(dict)
  end

-  def has_key?(dict, key) do
-    :lists.keymember(key, 1, dict)
-  end
+  def has_key?(dict, key)
+  def has_key?([{ key, _ }|_], key), do: true
+  def has_key?([{ _, _ }|t], key), do: has_key?(t, key)
+  def has_key?([], _key), do: false

-  def get(dict, key, default // nil) do
-    case :lists.keyfind(key, 1, dict) do
-      { ^key, value } -> value
-      false -> default
-    end
-  end
+  def get(dict, key, default // nil)
+  def get([{ key, value }|_], key, _default), do: value
+  def get([{ _, _ }|t], key, default), do: get(t, key, default)
+  def get([], _key, default), do: default

-  def fetch(dict, key) do
-    case :lists.keyfind(key, 1, dict) do
-      { ^key, value } -> { :ok, value }
-      false -> :error
-    end
-  end
+  def fetch(dict, key)
+  def fetch([{ key, value }|_], key), do: { :ok, value }
+  def fetch([{ _, _ }|t], key), do: fetch(t, key)
+  def fetch([], _key), do: :error

  def fetch!(dict, key) do
-    case :lists.keyfind(key, 1, dict) do
-      { ^key, value } -> value
-      false -> raise(KeyError, key: key)
+    case fetch(dict, key) do
+      { :ok, value } -> value
+      :error -> raise(KeyError, key: key)
    end
  end

@@ -72,26 +73,26 @@ defmodule ListDict do
  end

  def put_new(dict, key, val) do
-    case :lists.keyfind(key, 1, dict) do
-      { ^key, _ } -> dict
+    case has_key?(dict, key) do
+      true  -> dict
      false -> [{key, val}|dict]
    end
  end

-  def delete(dict, key) do
-    lc { k, _ } = tuple inlist dict, key != k, do: tuple
-  end
+  def delete(dict, key)
+  def delete([{ key, _ }|t], key), do: t
+  def delete([{ _, _ } = h|t], key), do: [h|delete(t, key)]
+  def delete([], _key), do: []

-  def merge(dict, enum, callback // fn(_k, _v1, v2) -> v2 end)
-
-  def merge(dict1, dict2, fun) do
-    Enum.reduce dict2, dict1, fn { k, v2 }, acc ->
-      update(acc, k, v2, fn(v1) -> fun.(k, v1, v2) end)
+  def merge(dict, enum, callback // fn(_k, _v1, v2) -> v2 end) do
+    Enum.reduce enum, dict, fn { k, v2 }, acc ->
+      update(acc, k, v2, fn(v1) -> callback.(k, v1, v2) end)
    end
  end

  def split(dict, keys) do
-    acc = { new(), new() }
+    acc = { [], [] }
+
    {take, drop} = Enum.reduce dict, acc, fn({ k, v }, { take, drop }) ->
      if :lists.member(k, keys) do
        { [{k, v}|take], drop }
@@ -99,7 +100,7 @@ defmodule ListDict do
        { take, [{k, v}|drop] }
      end
    end
-    
+
    {Enum.reverse(take), Enum.reverse(drop)}
  end

@@ -111,12 +112,6 @@ defmodule ListDict do
    lc { k, _ } = tuple inlist dict, not :lists.member(k, keys), do: tuple
  end

-  @doc false
-  def update(dict, key, fun) when is_function(fun, 1) do
-    IO.write "ListDict.update/3 is deprecated, please use ListDict.update!/3 instead\n#{Exception.format_stacktrace}"
-    update!(dict, key, fun)
-  end
-
  def update!([{key, value}|dict], key, fun) do
    [{key, fun.(value)}|delete(dict, key)]
  end
@@ -144,7 +139,7 @@ defmodule ListDict do
  def empty(_dict), do: []

  def equal?(dict, other) do
-    :lists.keysort(1, dict) == :lists.keysort(1, other)
+    :lists.keysort(1, dict) === :lists.keysort(1, other)
  end

  def to_list(dict), do: dict
@@ -5,6 +5,7 @@ defmodule Macro do
  This module provides conveniences for working with macros.
  """

+  @typedoc "Abstract Syntax Tree (AST) node"
  @type t :: { t, t } | { t, Keyword.t, t } | atom | number | binary | list

  @doc false
@@ -23,8 +24,7 @@ defmodule Macro do
    [:!, :@, :^, :not, :+, :-, :~~~, :&]
  end

-  @typep precedence :: integer # Higher means binds stronger
-  @spec binary_op_props(atom) :: { :left|:right, precedence }
+  @spec binary_op_props(atom) :: { :left | :right, precedence :: integer }
  defp binary_op_props(o) do
    case o do
      :::                                                       -> {:right, 30}
@@ -42,13 +42,47 @@ defmodule Macro do
      o when o in [:+, :-]                                      -> {:left, 210}
      o when o in [:*, :/]                                      -> {:left, 220}
      o when o in [:<>]                                         -> {:right, 230}
+      o when o in [:++, :--, :**]                               -> {:right, 240}
      :^^^                                                      -> {:left, 250}
      :.                                                        -> {:left, 310}
    end
  end

  @doc """
-  Receives an expresion representing a possible definition
+  Breaks a pipeline expression into a list. Raises if
+  the pipeline is ill-formed.
+  """
+  @spec unpipe(Macro.t) :: [Macro.t]
+  def unpipe({ :|> , _, [left, right] }) do
+    [left|unpipe(right)]
+  end
+
+  def unpipe(other) do
+    [other]
+  end
+
+  @doc """
+  Pipes the given `expr` in to the `call_expr` as the
+  argument in the given `position`.
+  """
+  @spec pipe(Macro.t, Macro.t, integer) :: Macro.t | no_return
+  def pipe(expr, call_args, integer // 0)
+
+  def pipe(expr, { call, line, atom }, integer) when is_atom(atom) do
+    { call, line, List.insert_at([], integer, expr) }
+  end
+
+  def pipe(expr, { call, line, args }, integer) when is_list(args) do
+    { call, line, List.insert_at(args, integer, expr) }
+  end
+
+  def pipe(expr, call_args, _integer) do
+    raise ArgumentError,
+      message: "cannot pipe #{to_string expr} into #{to_string call_args}"
+  end
+
+  @doc """
+  Receives an expression representing a possible definition
  and extracts its arguments. It returns a tuple with the
  function name and the arguments list or `:error` if not
  a valid call syntax.
@@ -89,22 +123,10 @@ defmodule Macro do
      1

  """
-  @spec escape(Macro.t) :: Macro.t
-  @spec escape(Macro.t, Keyword.t) :: Macro.t
+  @spec escape(term) :: Macro.t
+  @spec escape(term, Keyword.t) :: Macro.t
  def escape(expr, opts // []) do
-    :elixir_quote.escape(expr, Keyword.get(opts, :unquote, false)) |> elem(0)
-  end
-
-  @doc false
-  def unescape_binary(chars) do
-    IO.write "Macro.unescape_binary/1 is deprecated, please use Macro.unescape_string/1 instead\n#{Exception.format_stacktrace}"
-    unescape_string(chars)
-  end
-
-  @doc false
-  def unescape_binary(chars, map) do
-    IO.write "Macro.unescape_binary/2 is deprecated, please use Macro.unescape_string/2 instead\n#{Exception.format_stacktrace}"
-    unescape_string(chars, map)
+    elem(:elixir_quote.escape(expr, Keyword.get(opts, :unquote, false)), 0)
  end

  @doc %S"""
@@ -174,7 +196,7 @@ defmodule Macro do

  Using the unescape_map defined above is easy:

-      Macro.unescape_string "example\\n", unescape_map(&1)
+      Macro.unescape_string "example\\n", &unescape_map(&1)

  """
  @spec unescape_string(String.t, (non_neg_integer -> non_neg_integer | false)) :: String.t
@@ -221,7 +243,7 @@ defmodule Macro do

  # Variables
  def to_string({ var, _, atom } = ast, fun) when is_atom(atom) do
-    fun.(ast, atom_to_binary(var, :utf8))
+    fun.(ast, atom_to_binary(var))
  end

  # Aliases
@@ -252,22 +274,17 @@ defmodule Macro do
    fun.(ast, "{" <> Enum.map_join(args, ", ", &to_string(&1, fun)) <> "}")
  end

-  # List containers
-  def to_string({ :[], _, args } = ast, fun) do
-    fun.(ast, "[" <> Enum.map_join(args, ", ", &to_string(&1, fun)) <> "]")
-  end
-
  # Fn keyword
-  def to_string({ :fn, _, [[do: { :->, _, [{_, _, tuple}] } = arrow]] } = ast, fun)
+  def to_string({ :fn, _, [{ :->, _, [{_, _, tuple}] } = arrow] } = ast, fun)
      when not is_tuple(tuple) or elem(tuple, 0) != :__block__ do
    fun.(ast, "fn " <> arrow_to_string(arrow, fun) <> " end")
  end

-  def to_string({ :fn, _, [[do: { :->, _, [_] } = block]] } = ast, fun) do
+  def to_string({ :fn, _, [{ :->, _, [_] } = block] } = ast, fun) do
    fun.(ast, "fn " <> block_to_string(block, fun) <> "\nend")
  end

-  def to_string({ :fn, _, [[do: block]] } = ast, fun) do
+  def to_string({ :fn, _, [block] } = ast, fun) do
    block = adjust_new_lines block_to_string(block, fun), "\n  "
    fun.(ast, "fn\n  " <> block <> "\nend")
  end
@@ -294,16 +311,12 @@ defmodule Macro do
  end

  def to_string({ op, _, [arg] } = ast, fun) when op in unary_ops do
-    fun.(ast, atom_to_binary(op, :utf8) <> to_string(arg, fun))
+    fun.(ast, atom_to_binary(op) <> to_string(arg, fun))
  end

  # Access
  def to_string({ { :., _, [Kernel, :access] }, _, [left, right] } = ast, fun) do
-    fun.(ast, if right != [] and Keyword.keyword?(right) do
-      to_string(left, fun) <> to_string(right, fun)
-    else
-      to_string(left, fun) <> "[" <> to_string(right, fun) <> "]"
-    end)
+    fun.(ast, to_string(left, fun) <> to_string(right, fun))
  end

  # All other calls
@@ -321,11 +334,11 @@ defmodule Macro do
  end

  # Lists
-  def to_string(list = ast, fun) when is_list(list) do
+  def to_string(list, fun) when is_list(list) do
    if Keyword.keyword?(list) do
-      fun.(ast, "[" <> kw_list_to_string(list, fun) <> "]")
+      fun.(list, "[" <> kw_list_to_string(list, fun) <> "]")
    else
-      to_string({ :[], [], list }, fun)
+      fun.(list, "[" <> Enum.map_join(list, ", ", &to_string(&1, fun)) <> "]")
    end
  end

@@ -336,14 +349,14 @@ defmodule Macro do
  defmacrop kw_keywords, do: [:do, :catch, :rescue, :after, :else]

  defp is_kw_blocks?([_|_] = kw) do
-    Enum.all?(kw, match?({x, _} when x in kw_keywords, &1))
+    Enum.all?(kw, &match?({x, _} when x in kw_keywords, &1))
  end
  defp is_kw_blocks?(_), do: false

  defp module_to_string(atom, _fun) when is_atom(atom), do: inspect(atom, raw: true)
  defp module_to_string(other, fun), do: call_to_string(other, fun)

-  defp call_to_string(atom, _fun) when is_atom(atom), do: atom_to_binary(atom, :utf8)
+  defp call_to_string(atom, _fun) when is_atom(atom), do: atom_to_binary(atom)
  defp call_to_string({ :., _, [arg] }, fun),         do: module_to_string(arg, fun) <> "."
  defp call_to_string({ :., _, [left, right] }, fun), do: module_to_string(left, fun) <> "." <> call_to_string(right, fun)
  defp call_to_string(other, fun),                    do: to_string(other, fun)
@@ -375,7 +388,7 @@ defmodule Macro do

  defp kw_block_to_string(key, value, fun) do
    block = adjust_new_lines block_to_string(value, fun), "\n  "
-    atom_to_binary(key, :utf8) <> "\n  " <> block <> "\n"
+    atom_to_binary(key) <> "\n  " <> block <> "\n"
  end

  defp block_to_string({ :->, _, exprs }, fun) do
@@ -518,21 +531,21 @@ defmodule Macro do

  """
  def expand_once(ast, env) do
-    expand_once(ast, env, nil) |> elem(0)
+    elem(expand_once(ast, env, nil), 0)
  end

  defp expand_once({ :__aliases__, _, _ } = original, env, cache) do
-    case :elixir_aliases.expand(original, env.aliases, env.macro_aliases) do
+    case :elixir_aliases.expand(original, env.aliases, env.macro_aliases, env.lexical_tracker) do
      receiver when is_atom(receiver) ->
-        :elixir_tracker.record_alias(receiver, env.module)
+        :elixir_lexical.record_remote(receiver, env.lexical_tracker)
        { receiver, true, cache }
      aliases ->
-        aliases = lc alias inlist aliases, do: (expand_once(alias, env, cache) |> elem(0))
+        aliases = lc alias inlist aliases, do: elem(expand_once(alias, env, cache), 0)

-        case :lists.all(is_atom(&1), aliases) do
+        case :lists.all(&is_atom/1, aliases) do
          true ->
            receiver = :elixir_aliases.concat(aliases)
-            :elixir_tracker.record_alias(receiver, env.module)
+            :elixir_lexical.record_remote(receiver, env.lexical_tracker)
            { receiver, true, cache }
          false -> { original, false, cache }
        end
@@ -611,7 +624,7 @@ defmodule Macro do
  defp to_erl_env(_env, cache), do: cache

  defp is_partial?(args) do
-    :lists.any(match?({ :&, _, [_] }, &1), args)
+    :lists.any(&match?({ :&, _, [_] }, &1), args)
  end

  @doc """
@@ -620,7 +633,7 @@ defmodule Macro do
  expansion works and `expand_all/2` for recursive expansion.
  """
  def expand(tree, env) do
-    expand(tree, env, nil) |> elem(0)
+    elem(expand(tree, env, nil), 0)
  end

  @doc false # Used internally by Elixir
@@ -636,38 +649,6 @@ defmodule Macro do
    { tree, cache }
  end

-  @doc %S"""
-  Receives a AST node and expands it until it no longer represents
-  a macro. Then it expands all of its children recursively.
-
-  The documentation for `expand_once/2` goes into more detail
-  on how expansion works. Keep in mind that `expand_all/2` is
-  naive as it doesn't mutate the environment. Take this example:
-
-      quoted = quote do: __MODULE__
-      Macro.to_string Macro.expand_all(quoted, __ENV__)
-      #=> "nil"
-
-  The example above, works as expected. Outside of a module,
-  `__MODULE__` returns `nil`. Now consider this variation:
-
-      quoted = quote do
-        defmodule Foo, do: __MODULE__
-      end
-      Macro.to_string Macro.expand_all(quoted, __ENV__)
-      #=> "defmodule(Foo) do\n  nil\nend"
-
-  One would expect `__MODULE__` to be expanded to `Foo`
-  but that is not the case since all the expansion is done
-  based on the environment `__ENV__`. This behaviour is on
-  purpose, as the proper expansion would require passing through
-  the whole Elixir compiler by actually executing the code, which
-  is beyond the scope of this function.
-  """
-  def expand_all(tree, env) do
-    expand_all(tree, env, nil) |> elem(0)
-  end
-
  @doc false # Used internally by Elixir
  def expand_all(tree, env, cache) do
    expand_all_until(expand(tree, env, cache), env)
@@ -686,7 +667,7 @@ defmodule Macro do
  end

  defp expand_all_until({ list, cache }, env) when is_list(list) do
-    :lists.mapfoldl(expand_all(&1, env, &2), cache, list)
+    :lists.mapfoldl(&expand_all(&1, env, &2), cache, list)
  end

  defp expand_all_until({ other, cache }, _env) do
@@ -703,7 +684,7 @@ defmodule Macro do
    do_safe_term(terms) || :ok
  end

-  defp do_safe_term({ local, _, terms }) when local in [:{}, :[], :__aliases__] do
+  defp do_safe_term({ local, _, terms }) when local in [:{}, :__aliases__] do
    do_safe_term(terms)
  end

@@ -712,7 +693,7 @@ defmodule Macro do
  end

  defp do_safe_term({ left, right }), do: do_safe_term(left) || do_safe_term(right)
-  defp do_safe_term(terms) when is_list(terms),  do: Enum.find_value(terms, do_safe_term(&1))
+  defp do_safe_term(terms) when is_list(terms),  do: Enum.find_value(terms, &do_safe_term(&1))
  defp do_safe_term(terms) when is_tuple(terms), do: { :unsafe, terms }
  defp do_safe_term(_), do: nil
 end
@@ -34,14 +34,15 @@ defmodule Macro.Env do
  @type macros :: [{ module, [name_arity] }]
  @type context_modules :: [module]
  @type vars :: [{ atom, atom }]
+  @type lexical_tracker :: pid

-  fields = [:module, :file, :line, :function, :aliases, :context, :requires,
-            :functions, :macros, :context_modules, :macro_aliases, :vars]
+  fields = [:module, :file, :line, :function, :aliases, :context, :requires, :functions,
+            :macros, :context_modules, :macro_aliases, :vars, :lexical_tracker]

  types  = quote do: [module: module, file: file, line: line,
    function: name_arity, aliases: aliases, requires: requires,
    functions: functions, macros: macros, context_modules: context_modules,
-    macro_aliases: aliases, vars: vars]
+    macro_aliases: aliases, vars: vars, lexical_tracker: lexical_tracker]

  Record.deffunctions(fields, __MODULE__)
  Record.deftypes(fields, types, __MODULE__)
@@ -55,13 +56,13 @@ defmodule Macro.Env do
  end

  @doc """
-  Returns wether the compilation environment is currently
+  Returns whether the compilation environment is currently
  inside a guard.
  """
  def in_guard?(record), do: context(record) == :guard

  @doc """
-  Returns wether the compilation environment is currently
+  Returns whether the compilation environment is currently
  inside a match clause.
  """
  def in_match?(record), do: context(record) == :match
@@ -29,7 +29,7 @@ defmodule Module do
      When just a module is provided, the function is assumed to be
      `__after_compile__/2`.

-      **Example**
+      ### Example

          defmodule M do
            @after_compile __MODULE__
@@ -44,18 +44,20 @@ defmodule Module do
      A hook that will be invoked before the module is compiled.

      Accepts a module or a tuple `{ <module>, <function/macro atom> }`. The
-      function/macro must take one argument: the module environment. If it\'s a
+      function/macro must take one argument: the module environment. If it's a
      macro, its returned value will be injected at the end of the module definition
      before the compilation starts.

      When just a module is provided, the function/macro is assumed to be
      `__before_compile__/1`.

-      **Example**
+      Note: differently from `@after_compile`, the callback function/macro must
+      be placed in a separate module (because when the callback is invoked,
+      the current module does not yet exist).

-          defmodule M do
-            @before_compile __MODULE__
+      ### Example

+          defmodule A do
            defmacro __before_compile__(_env) do
              quote do
                def hello, do: "world"
@@ -63,11 +65,15 @@ defmodule Module do
            end
          end

+          defmodule B do
+            @before_compile A
+          end
+
  * `@behaviour`   (notice the british spelling)

      Specify an OTP or user-defined behaviour.

-      **Example**
+      ### Example

          defmodule M do
            @behaviour gen_event
@@ -85,7 +91,7 @@ defmodule Module do
      See http://www.erlang.org/doc/man/compile.html for the list of supported
      options.

-      **Example**
+      ### Example

            defmodule M do
              @compile { :inline, myfun: 1 }
@@ -106,7 +112,7 @@ defmodule Module do

      Can be invoked more than once.

-      **Example**
+      ### Example

            defmodule M do
              @doc "Hello world"
@@ -129,7 +135,7 @@ defmodule Module do

      Accepts a string. Can be used more than once.

-      **Example**
+      ### Example

            defmodule M do
              @doc "Hello world"
@@ -147,7 +153,7 @@ defmodule Module do
      `@moduledoc false` will make the module invisible to the
      documentation extraction tools like ExDoc.

-      **Example**
+      ### Example

            defmodule M do
              @moduledoc """
@@ -183,7 +189,7 @@ defmodule Module do
      function (i.e. `env.function` returns the current function), the hook
      can only be a function, not a macro.

-      **Example**
+      ### Example

            defmodule H do
              def on_def(_env, kind, name, args, guards, body) do
@@ -216,7 +222,7 @@ defmodule Module do
      must have arity 0 (no arguments) and has to return `:ok`, otherwise the
      loading of the module will be aborted.

-      **Example**
+      ### Example

            defmodule M do
              @on_load :load_check
@@ -238,7 +244,7 @@ defmodule Module do

      Specify the module version. Accepts any valid Elixir value.

-      **Example**
+      ### Example

            defmodule M do
              @vsn "1.0"
@@ -477,10 +483,11 @@ defmodule Module do
  end

  @doc """
-  Attaches documentation to a given function. It expects
-  the module the function belongs to, the line (a non negative
+  Attaches documentation to a given function or type. It expects
+  the module the function/type belongs to, the line (a non negative
  integer), the kind (def or defmacro), a tuple representing
-  the function and its arity and the documentation, which should
+  the function and its arity, the function signature (the signature
+  should be omitted for types) and the documentation, which should
  be either a binary or a boolean.

  ## Examples
@@ -491,12 +498,14 @@ defmodule Module do
      end

  """
-  def add_doc(_module, _line, kind, _tuple, _signature, doc) when kind in [:defp, :defmacrop] do
+  def add_doc(module, line, kind, tuple, signature // [], doc)
+
+  def add_doc(_module, _line, kind, _tuple, _signature, doc) when kind in [:defp, :defmacrop, :typep] do
    if doc, do: { :error, :private_doc }, else: :ok
  end

  def add_doc(module, line, kind, tuple, signature, doc) when
-      kind in [:def, :defmacro] and (is_binary(doc) or is_boolean(doc) or doc == nil) do
+      kind in [:def, :defmacro, :type, :opaque] and (is_binary(doc) or is_boolean(doc) or doc == nil) do
    assert_not_compiled!(:add_doc, module)
    table = docs_table_for(module)

@@ -5,15 +5,11 @@
 # ## Implementation
 #
 # The implementation uses the digraph module to track
-# all dependencies. The graph starts with three main
-# vertices:
+# all dependencies. The graph starts with one main vertice:
 #
 # * `:local` - points to local functions
-# * `:import` - points to imported modules
-# * `:warn` - points to imported modules that should be warned
-# * `:remote` - points to remote modules
 #
-# Besides those, we have can the following vertices:
+# We also have can the following vertices:
 #
 # * `Module` - a module that was invoked via an import or remotely
 # * `{ name, arity }` - a local function/arity pair
@@ -24,9 +20,7 @@
 # as described below:
 #
 # * `Module`
-#   * in neighbours: `:import`, `:remote`, `:warn`,
-#     `{ :import, name, arity }` and `{ :remote, name arity }`
-#   * out neighbours: `:warn`
+#   * in neighbours:  `{ :import, name, arity }` and `{ :remote, name arity }`
 #
 # * `{ name, arity }`
 #   * in neighbours: `:local`, `{ name, arity }`
@@ -92,15 +86,6 @@ defmodule Module.DispatchTracker do
    :digraph.out_neighbours(d, { name, arity }) |> only_tuples
  end

-  @doc """
-  Returns all the modules which were imported.
-  """
-  @spec imports(ref) :: [module]
-  def imports(ref) do
-    d = :gen_server.call(to_pid(ref), :digraph, @timeout)
-    :digraph.out_neighbours(d, :import)
-  end
-
  @doc """
  Returns all imported modules that had the given
  `{ name, arity }` invoked.
@@ -111,24 +96,6 @@ defmodule Module.DispatchTracker do
    :digraph.out_neighbours(d, { :import, name, arity })
  end

-  @doc """
-  Returns all the aliases defined in the given module.
-  """
-  @spec aliases(ref) :: [module]
-  def aliases(ref) do
-    d = :gen_server.call(to_pid(ref), :digraph, @timeout)
-    :digraph.out_neighbours(d, :alias)
-  end
-
-  @doc """
-  Returns all the modules which were remotely dispatched to.
-  """
-  @spec remotes(ref) :: [module]
-  def remotes(ref) do
-    d = :gen_server.call(to_pid(ref), :digraph, @timeout)
-    :digraph.out_neighbours(d, :remote)
-  end
-
  @doc """
  Returns all modules that had the given `{ name, arity }`
  invoked remotely.
@@ -157,7 +124,7 @@ defmodule Module.DispatchTracker do
    neighbours = (lc { _, _ } = t inlist neighbours, do: t) |> :ordsets.from_list
    remaining  = :ordsets.subtract(neighbours, vertices)
    vertices   = :ordsets.union(neighbours, vertices)
-    :lists.foldl(reduce_reachable(d, &1, &2), vertices, remaining)
+    :lists.foldl(&reduce_reachable(d, &1, &2), vertices, remaining)
  end

  defp to_pid(pid) when is_pid(pid),  do: pid
@@ -206,12 +173,6 @@ defmodule Module.DispatchTracker do
    :gen_server.cast(pid, { :add_local, from, to })
  end

-  # Adds an alias.
-  @doc false
-  def add_alias(pid, module) when is_atom(module) do
-    :gen_server.cast(pid, { :add_alias, module })
-  end
-
  # Adds a remote dispatch to the given target.
  @doc false
  def add_remote(pid, function, module, target) when is_atom(module) and is_tuple(target) do
@@ -224,40 +185,14 @@ defmodule Module.DispatchTracker do
    :gen_server.cast(pid, { :add_external, :import, function, module, target })
  end

-  # Associates a module with a warn. This adds the given
-  # module and associates it with the `:import` vertex
-  # permanently, even if warn is false.
-  @doc false
-  def add_warnable(pid, module, warn, line) when is_atom(module) and is_boolean(warn) do
-    :gen_server.cast(pid, { :add_warnable, module, warn, line })
-  end
-
-  # Collect all unused imports where warn has been set to true.
-  def collect_unused_imports(pid) do
-    d = :gen_server.call(pid, :digraph, @timeout)
-    warnable = :digraph.out_neighbours(d, :warn)
-
-    lc mod inlist warnable, not has_imports?(d, mod), line = get_warn_line(d, mod) do
-      { mod, line }
-    end
-  end
-
-  defp get_warn_line(d, mod) do
-    [edge] = :digraph.out_edges(d, mod)
-    { ^edge, ^mod, :warn, line } = :digraph.edge(d, edge)
-    line
-  end
-
-  defp has_imports?(d, mod) do
-    Enum.any?(:digraph.in_neighbours(d, mod), match?({ :import, _, _ }, &1))
-  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
    pid = to_pid(pid)
    add_definition(pid, kind, tuple)
@@ -282,7 +217,7 @@ defmodule Module.DispatchTracker do
  @doc false
  def collect_unused_locals(pid, private) do
    reachable = reachable(pid)
-    :lists.foldl(collect_unused_locals(&1, &2, reachable), [], private)
+    :lists.foldl(&collect_unused_locals(&1, &2, reachable), [], private)
  end

  defp collect_unused_locals({ tuple, kind, 0 }, acc, reachable) do
@@ -322,10 +257,6 @@ defmodule Module.DispatchTracker do
  def init([]) do
    d = :digraph.new([:protected])
    :digraph.add_vertex(d, :local)
-    :digraph.add_vertex(d, :alias)
-    :digraph.add_vertex(d, :import)
-    :digraph.add_vertex(d, :remote)
-    :digraph.add_vertex(d, :warn)
    { :ok, d }
  end

@@ -353,30 +284,11 @@ defmodule Module.DispatchTracker do
    { :noreply, d }
  end

-  def handle_cast({ :add_alias, module }, d) do
-    :digraph.add_vertex(d, module)
-    replace_edge!(d, :alias, module)
-    { :noreply, d }
-  end
-
  def handle_cast({ :add_external, kind, function, module, { name, arity } }, d) do
    handle_import_or_remote(d, kind, function, module, name, arity)
    { :noreply, d }
  end

-  def handle_cast({ :add_warnable, module, warn, line }, d) do
-    :digraph.add_vertex(d, module)
-    replace_edge!(d, :import, module)
-
-    if warn do
-      :digraph.add_edge(d, :warn, module, line)
-      :digraph.add_edge(d, module, :warn, line)
-    else
-      :digraph.del_path(d, :warn, module)
-    end
-    { :noreply, d }
-  end
-
  def handle_cast({ :add_definition, kind, tuple }, d) do
    handle_add_definition(d, kind, tuple)
    { :noreply, d }
@@ -414,7 +326,6 @@ defmodule Module.DispatchTracker do

  defp handle_import_or_remote(d, kind, function, module, name, arity) do
    :digraph.add_vertex(d, module)
-    replace_edge!(d, kind, module)

    tuple = { kind, name, arity }
    :digraph.add_vertex(d, tuple)
@@ -156,12 +156,12 @@ defmodule OptionParser do
        :boolean in kinds ->
          { nil, value in [true, "true"] }
        :integer in kinds ->
-          case String.to_integer(value) do
+          case Integer.parse(value) do
            { value, "" } -> { nil, value }
            _ -> { option, value }
          end
        :float in kinds ->
-          case String.to_float(value) do
+          case Float.parse(value) do
            { value, "" } -> { nil, value }
            _ -> { option, value }
          end
@@ -304,11 +304,11 @@ defmodule Process do
  end

  @doc """
-  Sets the group leader of Pid to GroupLeader. Typically, this is used when a processes
+  Sets the group leader of `pid` to `leader`. Typically, this is used when a processes
  started from a certain shell should have another group leader than `:init`.
  """
-  @spec group_leader(leader :: pid, pid) :: true
-  def group_leader(leader, pid) do
+  @spec group_leader(pid, leader :: pid) :: true
+  def group_leader(pid, leader) do
    :erlang.group_leader(leader, pid)
  end

@@ -1,58 +1,93 @@
 defmodule Protocol do
  @moduledoc false

-  # We need to use :lists because Enum is not available yet
-  require :lists, as: L
-
-  @doc """
-  Handle `defprotocol`. It will define a function for each
-  protocol plus two extra functions:
-
-  * `__protocol__/1` - returns the protocol name when :name is given,
-                       and a keyword 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
-  """
+  # Callback for defprotocol.
+  @doc false
  def defprotocol(name, [do: block]) do
    quote do
      defmodule unquote(name) do
        # We don't allow function definition inside protocols
        import Kernel, except: [
-          defmacrop: 1, defmacrop: 2, defmacrop: 4,
-          defmacro: 1, defmacro: 2, defmacro: 4,
-          defp: 1, defp: 2, defp: 4,
-          def: 1, def: 2, def: 4
+          defmacrop: 1, defmacrop: 2, defmacro: 1, defmacro: 2,
+          defp: 1, defp: 2, def: 1, def: 2
        ]

        # Import the new dsl that holds the new def
        import Protocol.DSL, only: :macros

+        # Compile with debug info for consolidation
+        @compile :debug_info
+
        # Set up a clear slate to store defined functions
        @functions []
+        @fallback_to_any false
+
+        # Deprecated
        @only nil
        @except nil

        # Invoke the user given block
        unquote(block)

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

-  @doc """
-  Implement the given protocol for the given module.
-  It also defines a `__impl__` function which
-  returns the protocol being implemented.
-  """
+  defp after_defprotocol do
+    quote unquote: false do
+      { arg, bodies, rec } = Protocol.impl_for(__MODULE__)
+
+      @spec impl_for(term) :: module | nil
+      Kernel.def impl_for(data)
+
+      lc { guard, body } inlist bodies do
+        Kernel.def impl_for(unquote(arg)) when unquote(guard), do: unquote(body)
+      end
+
+      @spec impl_for!(term) :: module | no_return
+      Kernel.def impl_for!(data) do
+        impl_for(data) || raise(Protocol.UndefinedError, protocol: __MODULE__, value: data)
+      end
+
+      # Handle special Record type
+      Kernel.defp rec_impl_for(unquote(arg)), do: unquote(rec)
+
+      # Handle special Any type
+      if @fallback_to_any do
+        Kernel.defp any_impl_for do
+          try do
+            __MODULE__.Any.__impl__(:name)
+          catch
+            :error, :undef, [[{ __MODULE__.Any, :__impl__, [:name], _ }|_]|_] ->
+              nil
+          end
+        end
+      else
+        Kernel.defp any_impl_for, do: nil
+      end
+
+      # Inline both helpers
+      @compile { :inline, any_impl_for: 0, rec_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, consolidated: false]
+
+      @doc false
+      Kernel.def __protocol__(:name),      do: __MODULE__
+      Kernel.def __protocol__(:functions), do: unquote(:lists.sort(@functions))
+    end
+  end
+
+  # Callback for defimpl.
+  @doc false
  def defimpl(protocol, opts) do
    do_defimpl(protocol, :lists.keysort(1, opts))
  end
@@ -76,6 +111,10 @@ defmodule Protocol do

        unquote(block)

+        Module.register_attribute(__MODULE__, :impl, persist: true)
+        @impl [protocol: @protocol, for: @for]
+
+        @doc false
        def __impl__(:name),     do: __MODULE__
        def __impl__(:protocol), do: @protocol
        def __impl__(:for),      do: @for
@@ -100,203 +139,88 @@ defmodule Protocol do
    end
  end

-  # 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.
+  # Builtin types.
  @doc false
-  def impl_for(conversions, fallback, returns_nil, env) do
-    contents = lc kind inlist conversions do
-      each_impl_for(kind, conversions, fallback)
-    end
-
-    if returns_nil do
-      contents = contents ++ [quote do
-        defp __raw_impl__(_) do
-          nil
-        end
-      end]
-    end
-
-    Module.eval_quoted env.module, contents, [], env.location
+  def builtin do
+    [ Tuple, Atom, List, BitString, Integer, Float,
+      Function, PID, Port, Reference, Any ]
  end

-  # Defines meta information about the protocol and internal callbacks.
+  # Implements the function that detects the protocol and
+  # returns the module to dispatch to.
  @doc false
-  def meta(functions, conversions, fallback, returns_nil, env) do
-    any     = L.keyfind(Any, 1, conversions) != false
-    records = L.keyfind(Record, 1, conversions) != false
+  def impl_for(current) do
+    arg = quote(do: arg)
+    all = [Record|builtin]

-    meta = quote location: :keep do
-      unless Kernel.Typespec.defines_type?(__MODULE__, :t, 0) do
-        @type t :: unquote(generate_type(conversions, any))
-      end
-
-      @doc false
-      def __protocol__(:name),      do: __MODULE__
-      def __protocol__(:functions), do: unquote(:lists.sort(functions))
-    end
-
-    impl_for = cond do
-      records and fallback ->
-        quote location: :keep do
-          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
-                catch
-                  :error, :undef, [[{ ^target, :__impl__, [], _ }|_]|_] ->
-                    unquote(fallback)
-                end
-              other ->
-                other
-            end
-          end
-        end
-      records ->
-        quote location: :keep do
-          def __impl_for__(arg) do
-            case __raw_impl__(arg) do
-              __MODULE__.Record ->
-                Module.concat(__MODULE__, :erlang.element(1, arg))
-              other ->
-                other
-            end
-          end
-        end
-      true ->
-        quote location: :keep do
-          def __impl_for__(arg), do: __raw_impl__(arg)
-        end
-    end
-
-    impl_bang = if returns_nil do
-      quote do
-        def __impl_for__!(arg) do
-          __impl_for__(arg) || raise(Protocol.UndefinedError, protocol: __MODULE__, value: arg)
-        end
-      end
-    else
-      quote do
-        def __impl_for__!(arg), do: __impl_for__(arg)
-      end
-    end
-
-    Module.eval_quoted env.module, [meta, impl_for, impl_bang], [], env.location
+    { arg,
+      lc(mod inlist all, do: impl_for(current, mod, arg)),
+      rec_impl_for(current, arg) }
  end

-  # Returns the default conversions according to the given
-  # only/except options.
-  @doc false
-  def conversions_for(module, only, except) do
-    kinds = all_types
+  defp rec_impl_for(current, arg) do
+    fallback = impl_for(current, Tuple, arg) |> elem(1)

-    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
-
-    # If any is not in the list and we don't implement all
-    # protocols, we need to handle nil cases.
-    returns_nil = L.keyfind(Any, 1, conversions) == false and length(conversions) < 10
-    { conversions, fallback, returns_nil }
-  end
-
-  ## Helpers
-
-  defp generate_type(_conversions, true) do
-    quote(do: any)
-  end
-
-  defp generate_type(conversions, false) do
-    or_function     = fn({ _, _, x }, acc) -> { :|, [], [acc, x] } end
-    { _, _, first } = hd(conversions)
-    :lists.foldl(or_function, first, tl(conversions))
-  end
-
-  defp all_types do
-    [ { Record,    :is_record,    quote do: tuple },
-      { Tuple,     :is_tuple,     quote do: tuple },
-      { Atom,      :is_atom,      quote do: atom },
-      { List,      :is_list,      quote do: list },
-      { BitString, :is_bitstring, quote do: <<>> },
-      { Number,    :is_number,    quote do: number },
-      { Function,  :is_function,  quote do: (... -> any) },
-      { PID,       :is_pid,       quote do: pid },
-      { Port,      :is_port,      quote do: port },
-      { Reference, :is_reference, quote do: reference },
-      { Any,       :is_any,       quote do: any } ]
-  end
-
-  # Returns a quoted expression that allows to check
-  # if the first item in the tuple is a 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
-
-  # We don't have a fallback, so we assume what was given
-  # as a record is indeed a record
-  defp each_impl_for({ _, :is_record, _ }, _conversions, nil) do
-    quote do
-      defp __raw_impl__(arg) when is_record(arg) do
-        __MODULE__.Record
+      target = Module.concat(unquote(current), unquote(arg))
+      try do
+        target.__impl__(:name)
+      catch
+        :error, :undef, [[{ ^target, :__impl__, [:name], _ }|_]|_] ->
+          unquote(fallback)
      end
    end
  end

-  # Specially handle records in the case we have fallbacks.
-  defp each_impl_for({ _, :is_record, _ }, conversions, fallback) do
-    quote do
-      defp __raw_impl__(arg) when is_record(arg) do
-        first = :erlang.element(1, arg)
-        case unquote(is_builtin?(conversions)) do
-          true  -> unquote(fallback)
-          false ->
-            case atom_to_list(first) do
-              'Elixir.' ++ _ -> __MODULE__.Record
-              _              -> unquote(fallback)
-            end
-        end
+  defp impl_for(current, Record, arg) do
+    fallback = impl_for(current, Tuple, arg) |> elem(1)
+
+    dispatch = quote do
+      atom = :erlang.element(1, unquote(arg))
+
+      case not(atom in unquote(builtin)) and match?('Elixir.' ++ _, atom_to_list(atom)) do
+        true  -> rec_impl_for(atom)
+        false -> unquote(fallback)
      end
    end
+
+    quote do
+      { is_record(unquote(arg)), unquote(dispatch) }
+    end
  end

-  # Special case any as we don't need to generate a guard.
-  defp each_impl_for({ _, :is_any, _ }, _, _) do
+  defp impl_for(current, Tuple, arg),     do: impl_with_fallback(Tuple, :is_tuple, current, arg)
+  defp impl_for(current, Atom, arg),      do: impl_with_fallback(Atom, :is_atom, current, arg)
+  defp impl_for(current, List, arg),      do: impl_with_fallback(List, :is_list, current, arg)
+  defp impl_for(current, BitString, arg), do: impl_with_fallback(BitString, :is_bitstring, current, arg)
+  defp impl_for(current, Integer, arg),   do: impl_with_fallback(Integer, :is_integer, current, arg)
+  defp impl_for(current, Float, arg),     do: impl_with_fallback(Float, :is_float, current, arg)
+  defp impl_for(current, Function, arg),  do: impl_with_fallback(Function, :is_function, current, arg)
+  defp impl_for(current, PID, arg),       do: impl_with_fallback(PID, :is_pid, current, arg)
+  defp impl_for(current, Port, arg),      do: impl_with_fallback(Port, :is_port, current, arg)
+  defp impl_for(current, Reference, arg), do: impl_with_fallback(Reference, :is_reference, current, arg)
+
+  defp impl_for(_current, Any, _arg) do
+    { true, quote(do: any_impl_for) }
+  end
+
+  # Defines an implementation with fallback to the given module.
+  defp impl_with_fallback(mod, guard, current, arg) do
    quote do
-      defp __raw_impl__(_) do
-        __MODULE__.Any
-      end
+      { unquote(guard)(unquote(arg)),
+        unquote(with_fallback(Module.concat(current, mod))) }
    end
  end

-  # Generate all others protocols.
-  defp each_impl_for({ kind, fun, _ }, _, _) do
+  # Tries to dispatch to a given target, fallbacks to the
+  # given `fallback` implementation if the target does not exist.
+  defp with_fallback(target) when is_atom(target) do
    quote do
-      defp __raw_impl__(arg) when unquote(fun)(arg) do
-        __MODULE__.unquote(kind)
+      try do
+        unquote(target).__impl__(:name)
+      catch
+        :error, :undef, [[{ unquote(target), :__impl__, [:name], _ }|_]|_] ->
+          any_impl_for
      end
    end
  end
@@ -305,36 +229,45 @@ end
 defmodule Protocol.DSL do
  @moduledoc false

-  # We need to use :lists because Enum is not available yet
-  require :lists, as: L
-
  @doc false
-  def args_and_body(module, name, arity) do
-    # 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>>), [], __MODULE__ }
-    end
+  defmacro def({ _, _, args }) when args == [] or is_atom(args) do
+    raise ArgumentError, message: "protocol functions expect at least one argument"
+  end

-    { conversions, fallback, returns_nil } = conversions_for(module)
-    clauses = [default_clause(name, args)]
+  defmacro def({ name, _, args }) when is_atom(name) and is_list(args) do
+    arity = length(args)

-    if returns_nil do
-      clauses = [nil_clause()|clauses]
-    end
+    type_args = lc _ inlist :lists.seq(2, arity), do: quote(do: term)
+    type_args = [quote(do: t) | type_args]

-    if L.keyfind(Record, 1, conversions) do
-      clauses = [record_clause(name, args, fallback)|clauses]
-    end
+    call_args = lc i inlist :lists.seq(2, arity),
+                  do: { binary_to_atom(<<?x, i + 64>>), [], __MODULE__ }
+    call_args = [quote(do: t) | call_args]

-    body =
-      quote do
-        case __raw_impl__(xA), do: unquote({ :->, [], clauses })
+    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

-    { args, body }
+      # Convert the spec to callback if possible,
+      # otherwise generate a dummy callback
+      Protocol.DSL.callback_from_spec(__MODULE__, name, arity) ||
+        @callback unquote(name)(unquote_splicing(type_args)) :: term
+    end
+  end
+
+  defmacro def(_) do
+    raise ArgumentError, message: "invalid args for def inside defprotocol"
  end

  @doc false
@@ -349,84 +282,4 @@ defmodule Protocol.DSL do

    found != []
  end
-
-  defp conversions_for(module) do
-    only   = Module.get_attribute(module, :only)
-    except = Module.get_attribute(module, :except)
-    Protocol.conversions_for(module, only, except)
-  end
-
-  defp default_clause(name, args) do
-    { [quote do: other],
-      [],
-      quote(do: apply(other, unquote(name), [unquote_splicing(args)])) }
-  end
-
-  defp nil_clause() do
-    { [nil],
-      [],
-      quote(do: raise(Protocol.UndefinedError, protocol: __MODULE__, value: xA)) }
-  end
-
-  defp record_clause(name, args, nil) do
-    { [quote(do: __MODULE__.Record)],
-      [],
-      quote(do: Module.concat(__MODULE__, :erlang.element(1, xA)).unquote(name)(unquote_splicing(args))) }
-  end
-
-  defp record_clause(name, args, fallback) do
-    arity = length(args)
-
-    { [quote(do: __MODULE__.Record)],
-      [],
-      quote do
-        target = Module.concat(__MODULE__, :erlang.element(1, xA))
-        try do
-          target.unquote(name)(unquote_splicing(args))
-        catch
-          :error, :undef, [[{ ^target, name, args, _ }|_]|_] when
-              name == unquote(name) and length(args) == unquote(arity) ->
-            apply unquote(fallback), name, [unquote_splicing(args)]
-        end
-      end }
-  end
-
-  defmacro def(expression) do
-    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) ->
-        :ok
-      _ ->
-        raise ArgumentError, message: "invalid args for defprotocol"
-    end
-
-    arity = length(args)
-
-    type_args = lc _ inlist :lists.seq(2, arity), do: quote(do: term)
-    type_args = [quote(do: t) | type_args]
-
-    meta = 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))
-
-      # Convert the spec to callback if possible,
-      # otherwise generate a dummy callback
-      Protocol.DSL.callback_from_spec(__MODULE__, name, arity) ||
-        @callback unquote(name)(unquote_splicing(type_args)) :: term
-    end
-
-    impl = quote bind_quoted: [name: name, arity: arity] do
-      { args, body } = Protocol.DSL.args_and_body(__MODULE__, name, arity)
-      Kernel.def unquote(name)(unquote_splicing(args)), do: unquote(body)
-    end
-
-    [meta, impl]
-  end
 end
@@ -0,0 +1,266 @@
+defmodule Protocol.Consolidation do
+  @moduledoc """
+  Module responsible for consolidating protocols and helpers for
+  extracting protocols and implementations from code paths for
+  consolidation.
+  """
+
+  @doc """
+  Extract all protocols from the given paths.
+
+  The paths can be either a char list or a string. Internally
+  they are worked on as char lists, so passing them as lists
+  avoid extra conversion.
+
+  ## Examples
+
+      # Get Elixir's ebin and retrieve all protocols
+      iex> path = :code.lib_dir(:elixir, :ebin)
+      iex> mods = Protocol.Consolidation.extract_protocols([path])
+      iex> Enumerable in mods
+      true
+
+  """
+  @spec extract_protocols([char_list | String.t]) :: [atom]
+  def extract_protocols(paths) do
+    extract_matching_by_attribute paths, 'Elixir.',
+      fn module, attributes ->
+        case attributes[:protocol] do
+          [fallback_to_any: _, consolidated: _] -> module
+          _ -> nil
+        end
+      end
+  end
+
+  @doc """
+  Extract all types implemented for the given protocol from
+  the given paths.
+
+  The paths can be either a char list or a string. Internally
+  they are worked on as char lists, so passing them as lists
+  avoid extra conversion.
+
+  ## Examples
+
+      # Get Elixir's ebin and retrieve all protocols
+      iex> path = :code.lib_dir(:elixir, :ebin)
+      iex> mods = Protocol.Consolidation.extract_impls(Enumerable, [path])
+      iex> List in mods
+      true
+
+  """
+  @spec extract_impls(module, [char_list | String.t]) :: [atom]
+  def extract_impls(protocol, paths) when is_atom(protocol) do
+    prefix = atom_to_list(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
+    lc path inlist paths,
+       file inlist 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_char_list(path))
+
+  defp extract_from_file(path, file, prefix, callback) do
+    if :lists.prefix(prefix, file) and Path.extname(file) == '.beam' do
+      extract_from_beam(Path.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
+
+  defmacrop if_ok(expr, call) do
+    quote do
+      case unquote(expr) do
+        { :ok, var } -> unquote(Macro.pipe(quote(do: var), call))
+        other -> other
+      end
+    end
+  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.
+
+  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:
+
+      Enumerable.__info__(:attributes)[:protocol]
+
+  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.
+  """
+  @spec apply_to(module, [module]) ::
+    { :ok, binary } |
+    { :error, :not_a_protocol } |
+    { :error, :no_beam_info }
+  def apply_to(protocol, types) when is_atom(protocol) do
+    ensure_protocol(protocol)
+    |> if_ok(change_debug_info types)
+    |> if_ok(compile)
+  end
+
+  # Ensure the given module is loaded and is a protocol.
+  defp ensure_protocol(protocol) do
+    case :beam_lib.chunks(beam_file(protocol), [:abstract_code, :attributes]) do
+      { :ok, { ^protocol, [abstract_code: { _raw, abstract_code },
+                           attributes: attributes] } } ->
+        case attributes[:protocol] do
+          [fallback_to_any: any, consolidated: _] ->
+            { :ok, { protocol, any, abstract_code } }
+          _ ->
+            { :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
+      :non_existing -> module
+      file -> file
+    end
+  end
+
+  # Change the debug information to the optimized
+  # impl_for/1 dispatch version.
+  defp change_debug_info({ protocol, any, code }, types) do
+    types   = if any, do: types, else: List.delete(types, Any)
+    records = types -- Protocol.builtin
+    builtin = Protocol.builtin -- (Protocol.builtin -- types)
+    builtin = if records != [], do: [Record|builtin], else: builtin
+    change_impl_for(code, protocol, builtin, records, false, [])
+  end
+
+  defp change_impl_for([{ :attribute, line, :protocol, _ }|t], protocol, builtin, records, _, acc) do
+    attr = [fallback_to_any: Any in builtin, consolidated: true]
+    change_impl_for(t, protocol, builtin, records, true,
+                    [{ :attribute, line, :protocol, attr }|acc])
+  end
+
+  defp change_impl_for([{ :function, line, :impl_for, 1, _ }|t], protocol, builtin, records, is_protocol, acc) do
+    clauses = lc type inlist builtin, do: clause_for(type, protocol, line)
+
+    unless Any in builtin do
+      clauses = clauses ++ [fallback_clause_for(nil, protocol, line)]
+    end
+
+    change_impl_for(t, protocol, builtin, records, is_protocol,
+                    [{ :function, line, :impl_for, 1, clauses }|acc])
+  end
+
+  defp change_impl_for([{ :function, line, :rec_impl_for, 1, _ }|t], protocol, builtin, records, is_protocol, acc) do
+    fallback = if Tuple in builtin, do: Module.concat(protocol, Tuple)
+    clauses  = lc type inlist records, do: record_clause_for(type, protocol, line)
+    clauses  = clauses ++ [fallback_clause_for(fallback, protocol, line)]
+
+    change_impl_for(t, protocol, builtin, records, is_protocol,
+                    [{ :function, line, :rec_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 clause_for(Tuple, protocol, line),     do: builtin_clause_for(Tuple, :is_tuple, protocol, line)
+  defp clause_for(Atom, protocol, line),      do: builtin_clause_for(Atom, :is_atom, protocol, line)
+  defp clause_for(List, protocol, line),      do: builtin_clause_for(List, :is_list, protocol, line)
+  defp clause_for(BitString, protocol, line), do: builtin_clause_for(BitString, :is_bitstring, protocol, line)
+  defp clause_for(Integer, protocol, line),   do: builtin_clause_for(Integer, :is_integer, protocol, line)
+  defp clause_for(Float, protocol, line),     do: builtin_clause_for(Float, :is_float, protocol, line)
+  defp clause_for(Function, protocol, line),  do: builtin_clause_for(Function, :is_function, protocol, line)
+  defp clause_for(PID, protocol, line),       do: builtin_clause_for(PID, :is_pid, protocol, line)
+  defp clause_for(Port, protocol, line),      do: builtin_clause_for(Port, :is_port, protocol, line)
+  defp clause_for(Reference, protocol, line), do: builtin_clause_for(Reference, :is_reference, protocol, line)
+
+  defp clause_for(Any, protocol, line) do
+    {:clause, line, [{:var, line, :_}], [],
+      [{ :atom, line, Module.concat(protocol, Any) }]}
+  end
+
+  defp clause_for(Record, _protocol, line) do
+    {:clause, line, [{:var, line, :x}],
+      [[{:op, line, :andalso,
+          {:call, line,
+            {:remote, line, {:atom, line, :erlang}, {:atom, line, :is_tuple}},
+            [{:var, line, :x}]},
+          {:call, line,
+            {:remote, line, {:atom, line, :erlang}, {:atom, line, :is_atom}},
+            [{:call, line,
+              {:remote, line, {:atom, line, :erlang}, {:atom, line, :element}},
+              [{:integer, line, 1}, {:var, line, :x}]
+            }]},
+      }]],
+      [{:call, line,
+          {:atom, line, :rec_impl_for},
+          [{:call, line,
+            {:remote, line, {:atom, line, :erlang}, {:atom, line, :element}},
+            [{:integer, line, 1}, {:var, line, :x}]}]}]}
+  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, Module.concat(protocol, mod)}]}
+  end
+
+  defp record_clause_for(other, protocol, line) do
+    {:clause, line, [{:atom, line, other}], [],
+      [{:atom, line, Module.concat(protocol, other)}]}
+  end
+
+  defp fallback_clause_for(value, _protocol, line) do
+    {:clause, line, [{:var, line, :_}], [],
+      [{ :atom, line, value }]}
+  end
+
+  # Finally compile the module and emit its bytecode.
+  defp compile({ protocol, code }) do
+    opts = if Code.compiler_options[:debug_info], do: [:debug_info], else: []
+    { :ok, ^protocol, binary, _warnings } = :compile.forms(code, [:return|opts])
+    { :ok, binary }
+  end
+end
@@ -17,21 +17,21 @@ defprotocol Range.Iterator do
 end

 defimpl Enumerable, for: Range do
-  def reduce(Range[first: first] = range, acc, fun) do
+  def reduce(first .. _ = range, acc, fun) do
    Range.Iterator.reduce(first, range, acc, fun)
  end

-  def member?(Range[first: first, last: last], value) do
-    value in first..last
+  def member?(first .. last, value) do
+    first <= value and value <= last
  end

-  def count(Range[first: first] = range) do
+  def count(first .. _ = range) do
    Range.Iterator.count(first, range)
  end
 end

-defimpl Range.Iterator, for: Number do
-  def reduce(first, Range[last: last], acc, fun) when is_integer(first) and is_integer(last) do
+defimpl Range.Iterator, for: Integer do
+  def reduce(first, Range[last: last], acc, fun) when is_integer(last) do
    reducer = if last >= first do
      fn(acc, fun) -> do_reducer_up(first, last, acc, fun) end
    else
@@ -56,11 +56,11 @@ defimpl Range.Iterator, for: Number do
    do_reducer_down(counter - 1, last, fun.(counter, acc), fun)
  end

-  def count(first, Range[last: last]) when is_integer(first) and is_integer(last) and last >= first do
+  def count(first, Range[last: last]) when is_integer(last) and last >= first do
    last - first + 1
  end

-  def count(first, Range[last: last]) when is_integer(first) and is_integer(last) do
+  def count(first, Range[last: last]) when is_integer(last) do
    first - last + 1
  end
 end
@@ -1,19 +1,19 @@
 defmodule Record do
  @moduledoc %S"""
-  Convenience functions for working with Records.
+  Functions for working with Records.

  A record is a tagged tuple which contains one or more elements
  where the first element is an atom. We can manually create a record
  by simply defining such a tuple:

-      iex> record = { User, "josé", 25 }
+      iex> record = { User, "José", 25 }
      iex> is_record(record, User)
      true

  However, manually constructing tuples can be quite error prone.
-  In case we need to add a new field to our User, it would require
+  If we need to add a new field to our User, it would require
  us to carefully change all places where the tuple is used.
-  Furthermore, as more and more items are added to the tuple, they
+  Furthermore, as more items are added to the tuple, they
  lose semantic value.

  This module solves these problems by allowing us to name each
@@ -38,7 +38,7 @@ defmodule Record do
  In the example above, `defrecordp` is going to generate a set of
  macros named `user` that allows us to create, update and match
  on a record. Our record is going to have two fields, a `name` with
-  default value of "José" and `age` of 25.
+  default value of "José" and `age` with default value 25.

  Let's see some examples:

@@ -75,10 +75,7 @@ defmodule Record do
  As the name says, `defrecordp` is useful when you don't want to
  expose the record definition. The `user` macro used above, for
  example, is only available inside the `User` module and nowhere else.
-  You can find more information in `Kernel.defrecordp/2` docs.
-
-  In general, though, records are used as part of a module's public
-  interface. For such use cases, Elixir provides record modules.
+  You can find more information in `Kernel.defrecordp/3` docs.

  ## defrecord

@@ -97,7 +94,7 @@ defmodule Record do
      user()        #=> User[name: "José", age: 25]
      user(age: 26) #=> User[name: "José", age: 26]

-  Notice that now, since the record definition is accessible, Elixir
+  Notice that now since the record definition is accessible, Elixir
  shows the record nicely formatted, no longer as a simple tuple. We
  can get the raw formatting by passing `raw: true` to `inspect`:

@@ -112,9 +109,9 @@ defmodule Record do
      User[]        #=> User[name: "José", age: 25]
      User[age: 26] #=> User[name: "José", age: 26]

-  The macro name is replaced by the module name and the parenthesis
-  are replaced by brackets. When the shortcut syntax is used, there
-  is no need to import the record.
+  The macro name is replaced by the module name and the parentheses
+  are replaced by brackets. When this syntax is used, there is no
+  need to import the record.

  Before we sum up the differences between `defrecord` and
  `defrecordp`, there is one last functionality introduced by
@@ -123,12 +120,12 @@ defmodule Record do
  ## Runtime access

  All the functionality discussed above happens at compilation time.
-  This means that both `user(user, age: 26)` and `User[user, age: 26]`
-  will be transformed into a simple tuple operation at compile time.
+  This means that both `user(age: 26)` and `User[age: 26]` are expanded
+  into a tuple at compile time.

  However, there are some situations where we want to set or update
-  fields dynamically. `defrecord` (and `defrecord` only) supports
-  it out of the box:
+  fields dynamically. `defrecord` (and not `defrecordp` ) supports
+  this behaviour out of the box:

      defrecord User, name: "José", age: 25

@@ -138,14 +135,23 @@ defmodule Record do
      user.update(age: 26)
      #=> User[name: "Hello", age: 26]

-  All the calls above happen at runtime. It gives Elixir
-  records flexibility at the cost of performance since
-  there is more work happening at runtime.
+  All the calls above happen at runtime. It gives Elixir records
+  flexibility at the cost of performance since there is more work
+  happening at runtime.

-  To sum up, `defrecordp` should be used when you don't want
-  to expose the record information while `defrecord` should be used
-  whenever you want to share a record within your code or with other
-  libraries or whenever you need to dynamically set or update fields.
+  The above calls (`new` and `update`) can accept both atom and string
+  keys for field names, however not both at the same time. This feature
+  allows to "sanitize" untrusted dictionaries and initialize/update
+  records without using `Kernel.binary_to_existing_atom/1`.
+
+  To sum up, `defrecordp` should be used when you don't want to expose
+  the record information while `defrecord` should be used whenever you
+  want to share a record within your code or with other libraries or
+  whenever you need to dynamically set or update fields.
+
+  The standard library contains excellent examples of both use cases,
+  with [`HashDict`](HashDict.html) being implemented with `defrecordp` 
+  and [`Range`](Range.html) with `defrecord`.

  You can learn more about records in the `Kernel.defrecord/3` docs. Now
  let's discuss the usefulness of combining records with protocols.
@@ -170,22 +176,30 @@ defmodule Record do
        end
      end

-  Now we can explicitly convert our WeekDate:
+  Now we can explicitly convert our `WeekDate`:

      to_string WeekDate[year: 2013, week: 26, week_day: 4]
      "2013-W26-4"

-  A protocol can be implemented for any record defined via `defrecord`.
+  A protocol can be implemented for any record, whether
+  generated with `defrecordp` or `defrecord`.
  """

  @type t :: tuple

  @doc """
-  Extract record information from an Erlang file and
-  return the fields as a list of tuples.
+  Extract record information from an Erlang file. 
+  
+  Returns the fields as a list of tuples.

  ## Examples

+      > Record.extract(:file_info, from_lib: "kernel/include/file.hrl")
+      [size: :undefined, type: :undefined, access: :undefined, atime: :undefined,
+         mtime: :undefined, ctime: :undefined, mode: :undefined, links: :undefined,
+          major_device: :undefined, minor_device: :undefined, inode: :undefined,
+           uid: :undefined, gid: :undefined]
+
      defrecord FileInfo, Record.extract(:file_info, from_lib: "kernel/include/file.hrl")

  """
@@ -194,8 +208,9 @@ defmodule Record do
  end

  @doc """
-  Imports a public record definition as a set of private macros,
-  as defined by `Kernel.defrecordp/2`. This is useful when one
+  Import a public record definition as a set of private macros.
+
+  Macros defined as in `Kernel.defrecordp/3`. This is useful when one
  desires to manipulate a record via a set of macros instead
  of the regular access syntax.

@@ -231,14 +246,14 @@ defmodule Record do
      unquoted_fields = unquote(fields)

      defmodule unquote(name) do
-        import Elixir.Record.DSL
+        import Record.DSL

        @record_fields []
        @record_types  []

-        Elixir.Record.deffunctions(unquoted_fields, __ENV__)
+        Record.deffunctions(unquoted_fields, __ENV__)
        value = unquote(block)
-        Elixir.Record.deftypes(@record_fields, @record_types, __ENV__)
+        Record.deftypes(@record_fields, @record_types, __ENV__)
        value
      end
    end
@@ -280,8 +295,9 @@ defmodule Record do
  end

  @doc """
-  Defines record functions skipping the module definition.
-  This is called directly by `defrecord`. It expects the record
+  Define record functions skipping the module definition.
+
+  This is called directly by `Kernel.defrecord/3`. It expects the record
  values, a set of options and the module environment.

  ## Examples
@@ -308,7 +324,7 @@ defmodule Record do

    contents = [quote(do: @record_fields unquote(escaped))|contents]

-    # Special case for bootstraping purposes
+    # Special case for bootstrapping purposes
    if env == Macro.Env do
      Module.eval_quoted(env, contents, [], [])
    else
@@ -317,7 +333,7 @@ defmodule Record do
  end

  @doc """
-  Defines types and specs for the record.
+  Define types and specs for the record.
  """
  def deftypes(values, types, env) do
    types  = types || []
@@ -339,8 +355,10 @@ defmodule Record do
  end

  @doc """
-  Defines macros for manipulating records. This is called
-  directly by `defrecordp`. It expects the macro name, the
+  Define macros for manipulating records. 
+  
+  This is called
+  directly by `Kernel.defrecordp/3`. It expects the macro name, the
  record values and the environment.

  ## Examples
@@ -414,7 +432,7 @@ defmodule Record do
  @doc false
  def access(atom, fields, keyword, caller) do
    unless is_keyword(keyword) do
-      raise ArgumentError, message: "expected contents inside brackets to be a Keyword"
+      raise ArgumentError, message: "expected contents inside brackets to be a keyword list, got: #{inspect keyword}"
    end

    in_match = caller.in_match?
@@ -627,9 +645,8 @@ defmodule Record do
    # an ordered dict of options (opts) and it will try to fetch
    # the given key from the ordered dict, falling back to the
    # default value if one does not exist.
-    selective = lc { k, v } inlist values do
-      quote do: Keyword.get(opts, unquote(k), unquote(v))
-    end
+    atom_selective   = lc { k, v } inlist values, do: initialize_lookup(k, v)
+    string_selective = lc { k, v } inlist values, do: initialize_lookup(atom_to_binary(k), v)

    quote do
      @doc false
@@ -637,7 +654,17 @@ defmodule Record do

      @doc false
      def new([]), do: { __MODULE__, unquote_splicing(defaults) }
-      def new(opts) when is_list(opts), do: { __MODULE__, unquote_splicing(selective) }
+      def new([{key, _}|_] = opts) when is_atom(key), do: { __MODULE__, unquote_splicing(atom_selective) }
+      def new([{key, _}|_] = opts) when is_binary(key), do: { __MODULE__, unquote_splicing(string_selective) }
+    end
+  end
+
+  defp initialize_lookup(k, v) do
+    quote do
+      case :lists.keyfind(unquote(k), 1, opts) do
+        false -> unquote(v)
+        {_, v} -> v
+      end
    end
  end

@@ -728,15 +755,14 @@ defmodule Record do
  # Define an updater method that receives a
  # keyword list and updates the record.
  defp updater(values) do
-    fields =
-      lc {key, _default} inlist values do
-        index = find_index(values, key, 1)
-        quote do
-          Keyword.get(keywords, unquote(key), elem(record, unquote(index)))
-        end
-      end
+    atom_fields =
+      lc {key, _default} inlist values, do: updater_lookup(key, key, values)

-    contents = quote do: { __MODULE__, unquote_splicing(fields) }
+    string_fields =
+      lc {key, _default} inlist values, do: updater_lookup(atom_to_binary(key), key, values)
+
+    atom_contents = quote do: { __MODULE__, unquote_splicing(atom_fields) }
+    string_contents = quote do: { __MODULE__, unquote_splicing(string_fields) }

    quote do
      @doc false
@@ -744,8 +770,22 @@ defmodule Record do
        record
      end

-      def update(keywords, record) do
-        unquote(contents)
+      def update([{key, _}|_] = keywords, record) when is_atom(key) do
+        unquote(atom_contents)
+      end
+      def update([{key, _}|_] = keywords, record) when is_binary(key) do
+        unquote(string_contents)
+      end
+    end
+  end
+
+  defp updater_lookup(k, key, values) do
+    v = find_index(values, key, 1)
+
+    quote do
+      case :lists.keyfind(unquote(k), 1, keywords) do
+        false -> elem(record, unquote(v))
+        {_, value} -> value
      end
    end
  end
@@ -768,6 +808,7 @@ defmodule Record do
  defp core_specs(values) do
    types   = lc { _, _, spec } inlist values, do: spec
    options = if values == [], do: [], else: [options_specs(values)]
+    values_specs = if values == [], do: [], else: values_specs(values)

    quote do
      unless Kernel.Typespec.defines_type?(__MODULE__, :t, 0) do
@@ -775,7 +816,7 @@ defmodule Record do
      end

      unless Kernel.Typespec.defines_type?(__MODULE__, :options, 0) do
-        @type options :: unquote(options)
+        @type options :: unquote(options) | [{String.t, unquote(values_specs)}]
      end

      @spec new :: t
@@ -793,6 +834,11 @@ defmodule Record do
      { :|, [], [{ k, v }, acc] }
    end, { k, v }, t
  end
+  defp values_specs([{ _, _, v }|t]) do
+    :lists.foldl fn { _, _, v }, acc ->
+      { :|, [], [v, acc] }
+    end, v, t
+  end

  defp accessor_specs([{ :__exception__, _, _ }|t], 1, acc) do
    accessor_specs(t, 2, acc)
@@ -814,7 +860,7 @@ defmodule Record do

  ## Helpers

-  defp is_keyword(list) when is_list(list), do: :lists.all(is_keyword_tuple(&1), list)
+  defp is_keyword(list) when is_list(list), do: :lists.all(&is_keyword_tuple/1, list)
  defp is_keyword(_), do: false

  defp is_keyword_tuple({ x, _ }) when is_atom(x), do: true
@@ -870,6 +916,7 @@ defmodule Record.DSL do

  @doc """
  Defines the type for each field in the record.
+
  Expects a keyword list.
  """
  defmacro record_type(opts) when is_list(opts) do
@@ -19,7 +19,7 @@ defmodule Record.Extractor do
  def retrieve(name, from_lib: file) when is_binary(file) do
    [app|path] = :filename.split(String.to_char_list!(file))

-    case :code.lib_dir(app) do
+    case :code.lib_dir(list_to_atom(app)) do
      { :error, _ } ->
        raise ArgumentError, message: "lib file #{file} could not be found"
      libpath ->
@@ -88,4 +88,4 @@ defmodule Record.Extractor do
    { :value, record, _ } = :erl_eval.expr(record_ast, [])
    record
  end
-end
+end
@@ -1,22 +1,21 @@
 defmodule Regex do
  @moduledoc %S"""
-  Regular expressions for Elixir built on top of the re module
+  Regular expressions for Elixir built on top of the `re` module
  in the Erlang Standard Library. More information can be found
-  in the re documentation: http://www.erlang.org/doc/man/re.html
+  in the [`re` documentation](http://www.erlang.org/doc/man/re.html).

-  Regular expressions in Elixir can be created using Regex.compile!
+  Regular expressions in Elixir can be created using `Regex.compile!`
  or using the special form with `%r`:

      # A simple regular expressions that matches foo anywhere in the string
      %r/foo/

-      # A regular expression with case insensitive options and handling for unicode chars
-      %r/foo/iu
+      # A regular expression with case insensitive options
+      %r/foo/i

-  The re module provides several options, the ones available in Elixir, followed by
+  The `re` module provides several options, the ones available in Elixir, followed by
  their shortcut in parenthesis, are:

-  * `unicode` (u) - enable unicode specific patterns like \p
  * `caseless` (i) - add case insensitivity
  * `dotall` (s) - causes dot to match newlines and also set newline to anycrlf.
    The new line setting can be overridden by setting `(*CR)` or `(*LF)` or
@@ -27,8 +26,8 @@ defmodule Regex do
    allow `#` to delimit comments
  * `firstline` (f) - forces the unanchored pattern to match before or at the first
    newline, though the matched text may continue over the newline
-  * `ungreedy` (r) - invert the "greediness" of the regexp
-  * `groups` (g) - compile with info about groups available
+  * `ungreedy` (r) - inverts the "greediness" of the regexp
+  * `groups` (g) - compiles with info about groups available

  The options not available are:

@@ -44,7 +43,7 @@ defmodule Regex do
  """

  defrecordp :regex, Regex, [:re_pattern, :source, :options, :groups]
-  @type t :: { Regex, term, binary, binary, [atom] }
+  @type t :: { Regex, term, binary, binary, [atom] | nil }

  defexception CompileError, message: "regex could not be compiled"

@@ -53,12 +52,20 @@ defmodule Regex do

  The given options can either be a binary with the characters
  representing the same regex options given to the `%r` sigil,
-  or a list of options, as expected by the Erlang `re` docs.
+  or a list of options, as expected by the [Erlang `re` docs](http://www.erlang.org/doc/man/re.html).

  It returns `{ :ok, regex }` in case of success,
  `{ :error, reason }` otherwise.
+
+  ## Examples
+
+      iex> Regex.compile("foo")
+      {:ok, %r"foo"}
+      iex> Regex.compile("*foo")
+      {:error, {'nothing to repeat', 0}}
+
  """
-  @spec compile(binary, binary | [term]) :: t
+  @spec compile(binary, binary | [term]) :: { :ok, t } | { :error, any }
  def compile(source, options // "")

  def compile(source, options) when is_binary(options) do
@@ -67,7 +74,9 @@ defmodule Regex do
        { :error, { :invalid_option, rest } }

      translated_options ->
-        compile(source, translated_options, options)
+        # Always use the unicode option, we don't have a latin1 legacy like
+        # Erlang.
+        compile(source, [:unicode|translated_options], options)
    end
  end

@@ -154,15 +163,15 @@ defmodule Regex do

  ## Examples

-      iex> Regex.captures(%r/c(?<foo>d)/g, "abcd")
+      iex> Regex.named_captures(%r/c(?<foo>d)/g, "abcd")
      [foo: "d"]
-      iex> Regex.captures(%r/a(?<foo>b)c(?<bar>d)/g, "abcd")
+      iex> Regex.named_captures(%r/a(?<foo>b)c(?<bar>d)/g, "abcd")
      [foo: "b", bar: "d"]
-      iex> Regex.captures(%r/a(?<foo>b)c(?<bar>d)/g, "efgh")
+      iex> Regex.named_captures(%r/a(?<foo>b)c(?<bar>d)/g, "efgh")
      nil

  """
-  def captures(regex(groups: groups) = regex, string, options // []) do
+  def named_captures(regex(groups: groups) = regex, string, options // []) do
    options = Keyword.put_new(options, :capture, :groups)
    results = run(regex, string, options)
    if results, do: Enum.zip(groups, results)
@@ -249,13 +258,14 @@ defmodule Regex do

    options = [{ :capture, captures, return }, :global]
    case :re.run(string, compiled, options) do
+      :match -> []
      :nomatch -> []
      { :match, results } -> results
    end
  end

  @doc """
-  Split the given target into the number of parts specified.
+  Splits the given target into the number of parts specified.
  If no number of parts is given, it defaults to `:infinity`.

  ## Examples
@@ -265,6 +275,10 @@ defmodule Regex do
      ["a","b-c"]
      iex> Regex.split(%r/-/, "abc")
      ["abc"]
+      iex> Regex.split(%r//, "abc")
+      ["a", "b", "c", ""]
+      iex> Regex.split(%r//, "abc", trim: true)
+      ["a", "b", "c"]
  """

  def split(regex, string, options // [])
@@ -354,7 +368,10 @@ defmodule Regex do
  defp return_for(element) when is_binary(element), do: :binary
  defp return_for(element) when is_list(element),   do: :list

-  defp translate_options(<<?u, t :: binary>>), do: [:unicode|translate_options(t)]
+  defp translate_options(<<?u, t :: binary>>) do
+    IO.write "The /u flag for regular expressions is no longer needed\n#{Exception.format_stacktrace}"
+    translate_options(t)
+  end
  defp translate_options(<<?i, t :: binary>>), do: [:caseless|translate_options(t)]
  defp translate_options(<<?x, t :: binary>>), do: [:extended|translate_options(t)]
  defp translate_options(<<?f, t :: binary>>), do: [:firstline|translate_options(t)]
@@ -15,6 +15,21 @@ defmodule Set do
  For simplicity's sake, in the examples below every time
  `new` is used, it implies one of the module-specific
  calls like above.
+
+  ## Protocols
+
+  Sets are required to implement the `Enumerable` protocol,
+  allowing one to write:
+
+      Enum.each(set, fn k ->
+        IO.inspect k
+      end)
+
+  ## Match
+
+  Sets are required to implement all operations
+  using the match (`===`) operator. Any deviation from
+  this behaviour should be avoided and explicitly documented.
  """

  use Behaviour
@@ -8,7 +8,7 @@ defmodule Stream do

      iex> range = 1..5
      1..5
-      iex> Enum.map range, &1 * 2
+      iex> Enum.map range, &(&1 * 2)
      [2,4,6,8,10]

  In the example above, as we mapped over the range, the elements being
@@ -16,8 +16,8 @@ defmodule Stream do
  module allows us to map the range, without triggering its enumeration:

      iex> range = 1..3
-      iex> stream = Stream.map(range, &1 * 2)
-      iex> Enum.map(stream, &1 + 1)
+      iex> stream = Stream.map(range, &(&1 * 2))
+      iex> Enum.map(stream, &(&1 + 1))
      [3,5,7]

  Notice we started with a range and then we created a stream that is
@@ -34,9 +34,9 @@ defmodule Stream do
  example:

      1..3 |>
-        Enum.map(IO.inspect(&1)) |>
-        Enum.map(&1 * 2) |>
-        Enum.map(IO.inspect(&1))
+        Enum.map(&IO.inspect(&1)) |>
+        Enum.map(&(&1 * 2)) |>
+        Enum.map(&IO.inspect(&1))
      1
      2
      3
@@ -50,9 +50,9 @@ defmodule Stream do
  was iterated three times. Let's see an example with streams:

      stream = 1..3 |>
-        Stream.map(IO.inspect(&1)) |>
-        Stream.map(&1 * 2) |>
-        Stream.map(IO.inspect(&1))
+        Stream.map(&IO.inspect(&1)) |>
+        Stream.map(&(&1 * 2)) |>
+        Stream.map(&IO.inspect(&1))
      Enum.to_list(stream)
      1
      2
@@ -81,8 +81,8 @@ defmodule Stream do

  This module also allows us to create streams from any enumerable:

-      iex> stream = Stream.map([1,2,3], &1 * 2)
-      iex> Enum.map(stream, &1 + 1)
+      iex> stream = Stream.map([1,2,3], &(&1 * 2))
+      iex> Enum.map(stream, &(&1 + 1))
      [3,5,7]

  By simply passing a list (which is an enumerable) as the first argument
@@ -187,7 +187,7 @@ defmodule Stream do
  """
  @spec cycle(Enumerable.t) :: t
  def cycle(enumerable) do
-    do_cycle(enumerable, &1, &2)
+    &do_cycle(enumerable, &1, &2)
  end

  defp do_cycle(enumerable, acc, fun) do
@@ -225,7 +225,7 @@ defmodule Stream do

  ## Examples

-      iex> stream = Stream.drop_while(1..10, &1 <= 5)
+      iex> stream = Stream.drop_while(1..10, &(&1 <= 5))
      iex> Enum.to_list(stream)
      [6,7,8,9,10]

@@ -271,7 +271,7 @@ defmodule Stream do

  ## Examples

-      iex> Stream.iterate(0, &1+1) |> Enum.take(5)
+      iex> Stream.iterate(0, &(&1+1)) |> Enum.take(5)
      [0,1,2,3,4]

  """
@@ -325,12 +325,30 @@ defmodule Stream do
  def flat_map(enumerable, f) do
    Lazy[enumerable: enumerable,
         fun: fn(f1) ->
-           fn(entry, acc) ->
-             Enumerable.reduce(f.(entry), acc, f1)
-           end
+           fn(entry, acc) -> do_flat_map(f.(entry), acc, f1) end
         end]
  end

+  defp do_flat_map(Lazy[] = lazy, acc, f1) do
+    try do
+      Enumerable.reduce(lazy, acc, fn x, y ->
+        try do
+          f1.(x, y)
+        catch
+          { :stream_lazy, nesting, rest } ->
+            throw({ :stream_flat_map, nesting, rest })
+        end
+      end)
+    catch
+      { :stream_flat_map, nesting, rest } ->
+        throw({ :stream_lazy, nesting, rest })
+    end
+  end
+
+  defp do_flat_map(enum, acc, f1) do
+    Enumerable.reduce(enum, acc, f1)
+  end
+
  @doc """
  Creates a stream that will reject elements according to
  the given function on enumeration.
@@ -352,7 +370,6 @@ defmodule Stream do
         end]
  end

-
  @doc """
  Returns a stream generated by calling `generator_fun` repeatedly.

@@ -365,7 +382,7 @@ defmodule Stream do
  @spec repeatedly((() -> element)) :: t
  def repeatedly(generator_fun)
  when is_function(generator_fun, 0) do
-    do_repeatedly(generator_fun, &1, &2)
+    &do_repeatedly(generator_fun, &1, &2)
  end

  defp do_repeatedly(generator_fun, acc, fun) do
@@ -388,7 +405,7 @@ defmodule Stream do

  """
  @spec take(Enumerable.t, non_neg_integer) :: t
-  def take(_enumerable, 0), do: Lazy[enumerable: [], fun: & &1]
+  def take(_enumerable, 0), do: Lazy[enumerable: [], fun: &(&1)]

  def take(enumerable, n) when n > 0 do
    Lazy[enumerable: enumerable,
@@ -407,7 +424,7 @@ defmodule Stream do

  ## Examples

-      iex> stream = Stream.take_while(1..100, &1 <= 5)
+      iex> stream = Stream.take_while(1..100, &(&1 <= 5))
      iex> Enum.to_list(stream)
      [1,2,3,4,5]

@@ -427,6 +444,31 @@ defmodule Stream do
         acc: true]
  end

+  @doc """
+  Emit a sequence of values and accumulators. Successive values are generated by
+  calling `next_fun` with the previous accumulator.
+
+  If the return value is nil iteration ends.
+
+  ## Examples
+
+      iex> Stream.unfold(5, fn 0 -> nil; n -> {n, n-1} end) |> Enum.to_list()
+      [5, 4, 3, 2, 1]
+  """
+  @spec unfold(acc, (acc -> { element, acc } | nil)) :: t
+  def unfold(acc, f) do
+    fn acc1, f1 ->
+      do_unfold(acc, f, acc1, f1)
+    end
+  end
+
+  defp do_unfold(gen_acc, gen_fun, acc, fun) do
+    case gen_fun.(gen_acc) do
+      nil                -> acc
+      { v, new_gen_acc } -> do_unfold(new_gen_acc, gen_fun, fun.(v, acc), fun)
+    end
+  end
+
  @doc """
  Creates a stream where each item in the enumerable will
  be accompanied by its index.
@@ -1,3 +1,5 @@
+import Kernel, except: [length: 1]
+
 defmodule String do
  @moduledoc %S"""
  A String in Elixir is a UTF-8 encoded binary.
@@ -5,7 +7,7 @@ defmodule String do
  ## String and binary operations

  The functions in this module act according to the
-  Unicode Standard, version 6.2.0. For example,
+  Unicode Standard, version 6.3.0. For example,
  `capitalize/1`, `downcase/1`, `strip/1` are provided by this
  module.

@@ -16,7 +18,7 @@ defmodule String do
  * `Kernel.binary_part/3` - retrieves part of the binary
  * `Kernel.bit_size/1` and `Kernel.byte_size/1` - size related functions
  * `Kernel.is_bitstring/1` and `Kernel.is_binary/1` - type checking function
-  * Plus a number of conversion functions, like `Kernel.binary_to_atom/2`,
+  * Plus a number of conversion functions, like `Kernel.binary_to_atom/1`,
    `Kernel.binary_to_integer/2`, `Kernel.binary_to_term/1` and their inverses,
    like `Kernel.integer_to_binary/2`

@@ -30,10 +32,14 @@ defmodule String do
  For example, the character "é" is represented with two
  bytes:

-      iex> string = "é"
-      ...> byte_size(string)
+      iex> byte_size("é")
      2

+  However, this module returns the proper length:
+
+      iex> String.length("é")
+      1
+
  Furthermore, this module also presents the concept of
  graphemes, which are multiple characters that may be
  "perceived as a single character" by readers. For example,
@@ -43,6 +49,8 @@ defmodule String do
      iex> string = "\x{0065}\x{0301}"
      ...> byte_size(string)
      3
+      iex> String.length(string)
+      1

  Although the example above is made of two characters, it is
  perceived by users as one.
@@ -57,6 +65,11 @@ defmodule String do
  Standard, but does not contain any of the locale specific
  behaviour.

+  More information about graphemes can be found in the [Unicode
+  Standard Annex #29](http://www.unicode.org/reports/tr29/).
+  This current Elixir version implements Extended Grapheme Cluster
+  algorithm.
+
  ## Integer codepoints

  Although codepoints could be represented as integers, this
@@ -139,7 +152,7 @@ defmodule String do
  def printable?(_),    do: false

  @doc """
-  Splits a string on substrings at each Unicode whitespace
+  Divides a string into substrings at each Unicode whitespace
  occurrence with leading and trailing whitespace ignored.

  ## Examples
@@ -155,7 +168,7 @@ defmodule String do
  @spec split(t) :: [t]
  defdelegate split(binary), to: String.Unicode

-  @doc """
+  @doc %S"""
  Divides a string into substrings based on a pattern,
  returning a list of these substrings. The pattern can
  be a string, a list of strings or a regular expression.
@@ -168,6 +181,8 @@ defmodule String do

  ## Examples

+  Splitting with a string pattern:
+
      iex> String.split("a,b,c", ",")
      ["a", "b", "c"]
      iex> String.split("a,b,c", ",", global: false)
@@ -175,15 +190,30 @@ defmodule String do
      iex> String.split(" a b c ", " ", trim: true)
      ["a", "b", "c"]

+  A list of patterns:
+
      iex> String.split("1,2 3,4", [" ", ","])
      ["1", "2", "3", "4"]

+  A regular expression:
+
      iex> String.split("a,b,c", %r{,})
      ["a", "b", "c"]
      iex> String.split("a,b,c", %r{,}, global: false)
      ["a", "b,c"]
-      iex> String.split("a,b", %r{\\.})
-      ["a,b"]
+      iex> String.split(" a b c ", %r{\s}, trim: true)
+      ["a", "b", "c"]
+
+  Splitting on empty patterns returns codepoints:
+
+      iex> String.split("abc", %r{})
+      ["a", "b", "c", ""]
+      iex> String.split("abc", "")
+      ["a", "b", "c", ""]
+      iex> String.split("abc", "", trim: true)
+      ["a", "b", "c"]
+      iex> String.split("abc", "", global: false)
+      ["a", "bc"]

  """
  @spec split(t, t | [t] | Regex.t) :: [t]
@@ -192,6 +222,8 @@ defmodule String do

  def split("", _pattern, _options), do: [""]

+  def split(binary, "", options), do: split(binary, %r"", options)
+
  def split(binary, pattern, options) when is_regex(pattern) do
    Regex.split(pattern, binary, options)
  end
@@ -435,13 +467,13 @@ defmodule String do
  end

  defp do_justify(subject, len, padding, type) when is_integer(padding) do
-    subject_len = String.length(subject)
+    subject_len = length(subject)

    cond do
      subject_len >= len ->
        subject
      subject_len < len ->
-        fill = String.duplicate(<<padding :: utf8>>, len - subject_len)
+        fill = duplicate(<<padding :: utf8>>, len - subject_len)

        case type do
          :left  -> subject <> fill
@@ -523,11 +555,11 @@ defmodule String do
  """
  @spec reverse(t) :: t
  def reverse(string) do
-    do_reverse(String.Unicode.next_grapheme(string), [])
+    do_reverse(next_grapheme(string), [])
  end

  defp do_reverse({grapheme, rest}, acc) do
-    do_reverse(String.Unicode.next_grapheme(rest), [grapheme|acc])
+    do_reverse(next_grapheme(rest), [grapheme|acc])
  end

  defp do_reverse(:no_grapheme, acc), do: iolist_to_binary(acc)
@@ -584,6 +616,7 @@ defmodule String do
      { "j", "osé" }

  """
+  @compile { :inline, next_codepoint: 1 }
  @spec next_codepoint(t) :: {codepoint, t} | :no_codepoint
  defdelegate next_codepoint(string), to: String.Unicode

@@ -642,30 +675,10 @@ defmodule String do
  def valid_character?(<<_ :: utf8>> = codepoint), do: valid?(codepoint)
  def valid_character?(_), do: false

-  @doc %S"""
-  Checks whether `str` is a valid codepoint.
-
-  Note that the empty string is considered invalid, as are
-  strings containing multiple codepoints.
-
-  ## Examples
-
-      iex> String.valid_codepoint?("a")
-      true
-      iex> String.valid_codepoint?("ø")
-      true
-      iex> String.valid_codepoint?(<<0xffff :: 16>>)
-      false
-      iex> String.valid_codepoint?("asdf")
-      false
-
-  """
-  @spec valid_codepoint?(codepoint) :: boolean
-  def valid_codepoint?(<<_ :: utf8>>), do: true
-  def valid_codepoint?(_), do: false
-
  @doc """
-  Returns unicode graphemes in the string.
+  Returns unicode graphemes in the string as per Extended Grapheme
+  Cluster algorithm outlined in the [Unicode Standard Annex #29,
+  Unicode Text Segmentation](http://www.unicode.org/reports/tr29/).

  ## Examples

@@ -674,7 +687,7 @@ defmodule String do

  """
  @spec graphemes(t) :: [grapheme]
-  defdelegate graphemes(string), to: String.Unicode
+  defdelegate graphemes(string), to: String.Graphemes

  @doc """
  Returns the next grapheme in a String.
@@ -689,8 +702,9 @@ defmodule String do
      { "j", "osé" }

  """
+  @compile { :inline, next_grapheme: 1 }
  @spec next_grapheme(t) :: { grapheme, t } | :no_grapheme
-  defdelegate next_grapheme(string), to: String.Unicode
+  defdelegate next_grapheme(string), to: String.Graphemes

  @doc """
  Returns the first grapheme from an utf8 string,
@@ -782,7 +796,7 @@ defmodule String do
  end

  def at(string, position) when position < 0 do
-    real_pos = do_length(next_grapheme(string)) - abs(position)
+    real_pos = length(string) - abs(position)
    case real_pos >= 0 do
      true  -> do_at(next_grapheme(string), real_pos, 0)
      false -> nil
@@ -827,7 +841,7 @@ defmodule String do
  @spec slice(t, integer, integer) :: grapheme | nil

  def slice(string, start, 0) do
-    case abs(start) <= String.length(string) do
+    case abs(start) <= length(string) do
      true -> ""
      false -> nil
    end
@@ -838,13 +852,72 @@ defmodule String do
  end

  def slice(string, start, len) when start < 0 and len >= 0 do
-    real_start_pos = do_length(next_grapheme(string)) - abs(start)
+    real_start_pos = length(string) - abs(start)
    case real_start_pos >= 0 do
      true -> do_slice(next_grapheme(string), real_start_pos, real_start_pos + len - 1, 0, "")
      false -> nil
    end
  end

+  @doc """
+  Returns a substring from the offset given by the start of the
+  range to the offset given by the end of the range.
+
+  If the start of the range is not a valid offset for the given
+  string or if the range is in reverse order, returns `nil`.
+
+  ## Examples
+
+      iex> String.slice("elixir", 1..3)
+      "lix"
+      iex> String.slice("elixir", 1..10)
+      "lixir"
+      iex> String.slice("elixir", 10..3)
+      nil
+
+      iex> String.slice("elixir", -4..-1)
+      "ixir"
+      iex> String.slice("elixir", 2..-1)
+      "ixir"
+      iex> String.slice("elixir", -4..6)
+      "ixir"
+      iex> String.slice("elixir", -1..-4)
+      nil
+      iex> String.slice("elixir", -10..-7)
+      nil
+
+      iex> String.slice("a", 0..1500)
+      "a"
+      iex> String.slice("a", 1..1500)
+      ""
+      iex> String.slice("a", 2..1500)
+      nil
+
+  """
+  @spec slice(t, Range.t) :: t | nil
+
+  def slice(string, range)
+
+  def slice(string, first..last) when first >= 0 and last >= 0 do
+    do_slice(next_grapheme(string), first, last, 0, "")
+  end
+
+  def slice(string, first..last) do
+    total = length(string)
+
+    if first < 0 do
+      first = total + first
+    end
+
+    if last < 0 do
+      last = total + last
+    end
+
+    if first > 0 do
+      do_slice(next_grapheme(string), first, last, 0, "")
+    end
+  end
+
  defp do_slice(_, start_pos, last_pos, _, _) when start_pos > last_pos do
    nil
  end
@@ -872,64 +945,6 @@ defmodule String do
    end
  end

-  @doc """
-  Converts a string to an integer. If successful, returns a
-  tuple of the form `{integer, remainder of string}`. If unsuccessful,
-  returns `:error`.
-
-  ## Examples
-
-      iex> String.to_integer("34")
-      {34,""}
-      iex> String.to_integer("34.5")
-      {34,".5"}
-      iex> String.to_integer("three")
-      :error
-
-  """
-  @spec to_integer(t) :: {integer, t} | :error
-
-  def to_integer(string) do
-    {result, remainder} = :string.to_integer(:binary.bin_to_list(string))
-    case result do
-      :error -> :error
-      _ -> {result, :binary.list_to_bin(remainder)}
-    end
-  end
-
-  @doc """
-  Converts a string to a float. If successful, returns a
-  tuple of the form `{float, remainder of string}`.
-  If unsuccessful, returns `:error`.
-
-  ## Examples
-
-      iex> String.to_float("34")
-      {34.0,""}
-      iex> String.to_float("34.25")
-      {34.25,""}
-      iex> String.to_float("56.5xyz")
-      {56.5,"xyz"}
-      iex> String.to_float("pi")
-      :error
-
-  """
-  @spec to_float(t) :: {integer, t} | :error
-
-  def to_float(string) do
-    charlist = :binary.bin_to_list(string)
-    {result, remainder} = :string.to_float(charlist)
-    case result do
-      :error ->
-        {int_result, int_remainder} = :string.to_integer(charlist)
-        case int_result do
-          :error -> :error
-          _ -> {:erlang.float(int_result), :binary.list_to_bin(int_remainder)}
-        end
-      _ -> {result, :binary.list_to_bin(remainder)}
-    end
-  end
-
  @doc """
  Returns `true` if `string` starts with any of the prefixes given, otherwise
  `false`. `prefixes` can be either a single prefix or a list of prefixes.
@@ -947,7 +962,7 @@ defmodule String do
  @spec starts_with?(t, t | [t]) :: boolean

  def starts_with?(string, prefixes) when is_list(prefixes) do
-    Enum.any?(prefixes, do_starts_with(string, &1))
+    Enum.any?(prefixes, &do_starts_with(string, &1))
  end

  def starts_with?(string, prefix) do
@@ -983,7 +998,7 @@ defmodule String do
  @spec ends_with?(t, t | [t]) :: boolean

  def ends_with?(string, suffixes) when is_list(suffixes) do
-    Enum.any?(suffixes, do_ends_with(string, &1))
+    Enum.any?(suffixes, &do_ends_with(string, &1))
  end

  def ends_with?(string, suffix) do
@@ -1022,7 +1037,7 @@ defmodule String do
  @spec contains?(t, t | [t]) :: boolean

  def contains?(string, matches) when is_list(matches) do
-    Enum.any?(matches, do_contains(string, &1))
+    Enum.any?(matches, &do_contains(string, &1))
  end

  def contains?(string, match) do
@@ -14,8 +14,6 @@ defprotocol String.Chars do
  as `"foo" <> to_string(bar)`.
  """

-  @only [BitString, List, Number, Atom, Record]
-
  def to_string(thing)
 end

@@ -29,7 +27,7 @@ defimpl String.Chars, for: Atom do
  end

  def to_string(atom) do
-    atom_to_binary(atom, :utf8)
+    atom_to_binary(atom)
  end
 end

@@ -67,14 +65,19 @@ defimpl String.Chars, for: List do
  def to_string(char_list), do: String.from_char_list!(char_list)
 end

-defimpl String.Chars, for: Number do
+defimpl String.Chars, for: Integer do
  @doc """
-  Simply converts the number (integer or a float) to a binary.
+  Simply converts the integer to a string.
  """
-  def to_string(thing) when is_integer(thing) do
+  def to_string(thing) do
    integer_to_binary(thing)
  end
+end

+defimpl String.Chars, for: Float do
+  @doc """
+  Simply converts the float to a string.
+  """
  def to_string(thing) do
    iolist_to_binary(:io_lib_format.fwrite_g(thing))
  end
@@ -9,8 +9,8 @@ defmodule System do
    message: "could not get a current working directory, the current location is not accessible"

  @moduledoc """
-  The System module provides access to some variables used or
-  maintained by the VM and to functions that interact strongly
+  The System module provides access to variables used or
+  maintained by the VM and to functions that interact directly
  with the VM or the host system.
  """

@@ -57,13 +57,17 @@ defmodule System do
  end

  @doc """
+  Elixir version information.
+
  Returns Elixir's version as binary.
  """
  @spec version() :: String.t
  def version, do: get_version

  @doc """
-  Returns a keywords list with version, git tag info and date.
+  Elixir build information.
+
+  Returns a keyword list with Elixir version, git tag info and compilation date.
  """
  @spec build_info() :: Keyword.t
  def build_info do
@@ -71,7 +75,9 @@ defmodule System do
  end

  @doc """
-  Returns the list of command-line arguments passed to the program.
+  List command line arguments.
+
+  Returns the list of command line arguments passed to the program.
  """
  @spec argv() :: [String.t]
  def argv do
@@ -79,15 +85,19 @@ defmodule System do
  end

  @doc """
-  Changes the list of command-line arguments. Use it with caution,
-  as it destory any previous argv information.
+  Modify command line arguments.
+
+  Changes the list of command line arguments. Use it with caution,
+  as it destroys any previous argv information.
  """
  @spec argv([String.t]) :: :ok
-  def argv(argv) do
-    :elixir_code_server.cast({ :argv, argv })
+  def argv(args) do
+    :elixir_code_server.cast({ :argv, args })
  end

  @doc """
+  Current working directory.
+
  Returns the current working directory or `nil` if one
  is not available.
  """
@@ -99,6 +109,8 @@ defmodule System do
  end

  @doc """
+  Current working directory, exception on error.
+
  Returns the current working directory or raises `System.NoAccessCwdError`.
  """
  def cwd! do
@@ -106,8 +118,10 @@ defmodule System do
  end

  @doc """
-  Returns the user home (platform independent).
-  It returns `nil` if no user home is set.
+  User home directory.
+
+  Returns the user home directory (platform independent).
+  Returns `nil` if no user home is set.
  """
  def user_home do
    case :os.type() do
@@ -117,6 +131,8 @@ defmodule System do
  end

  @doc """
+  User home directory, exception on error.
+
  Same as `user_home/0` but raises `System.NoHomeError`
  instead of returning `nil` if no user home is set.
  """
@@ -139,8 +155,10 @@ defmodule System do
  end

  @doc %S"""
+  Writable temporary directory.
+
  Returns a writable temporary directory.
-  It searches for directories in the following order:
+  Searches for directories in the following order:

  1. The directory named by the TMPDIR environment variable
  2. The directory named by the TEMP environment variable
@@ -159,7 +177,9 @@ defmodule System do
  end

  @doc """
-  Same as `tmp_dir` but raises `System.NoTmpDirError`
+  Writable temporary directory, exception on error.
+
+  Same as `tmp_dir/0` but raises `System.NoTmpDirError`
  instead of returning `nil` if no temp dir is set.
  """
  def tmp_dir! do
@@ -189,18 +209,22 @@ defmodule System do
  end

  @doc """
+  Register a program exit handler function.
+
  Registers a function that will be invoked
  at the end of program execution. Useful for
-  invoking a hook in a "script" mode.
+  invoking a hook in "script" mode.

-  The function must expect the exit status code
-  as argument.
+  The function must receive the exit status code
+  as an argument.
  """
  def at_exit(fun) when is_function(fun, 1) do
    :elixir_code_server.cast { :at_exit, fun }
  end

  @doc """
+  Execute a system command.
+
  Executes `command` in a command shell of the target OS,
  captures the standard output of the command and returns
  the result as a binary.
@@ -222,6 +246,8 @@ defmodule System do
  end

  @doc """
+  Locate an executable on the system.
+
  This function looks up an executable program given
  its name using the environment variable PATH on Unix
  and Windows. It also considers the proper executable
@@ -248,6 +274,8 @@ defmodule System do
  end

  @doc """
+  System environment variables.
+
  Returns a list of all environment variables. Each variable is given as a
  `{name, value}` tuple where both `name` and `value` are strings.
  """
@@ -261,6 +289,8 @@ defmodule System do
  end

  @doc """
+  Environment variable value.
+
  Returns the value of the environment variable
  `varname` as a binary, or `nil` if the environment
  variable is undefined.
@@ -274,6 +304,8 @@ defmodule System do
  end

  @doc """
+  Erlang VM process identifier.
+
  Returns the process identifier of the current Erlang emulator
  in the format most commonly used by the operating system environment.

@@ -283,6 +315,8 @@ defmodule System do
  def get_pid, do: iolist_to_binary(:os.getpid)

  @doc """
+  Set an environment variable value.
+
  Sets a new `value` for the environment variable `varname`.
  """
  @spec put_env(binary, binary) :: :ok
@@ -292,6 +326,8 @@ defmodule System do
  end

  @doc """
+  Set multiple environment variables.
+
  Sets a new value for each environment variable corresponding
  to each key in `dict`.
  """
@@ -301,22 +337,24 @@ defmodule System do
  end

  @doc """
-  Gets Elixir's stacktrace.
+  Last exception stacktrace.

-  Notice the Erlang VM (and therefore this function) does not
+  Note that the Erlang VM (and therefore this function) does not
  return the current stacktrace but rather the stacktrace of the
  latest exception.
  """
  def stacktrace do
-    filter_stacktrace :erlang.get_stacktrace
+    :erlang.get_stacktrace
  end

  @doc """
-  Halts the Erlang runtime system where the first argument status must be a
+  Halt the Erlang runtime system.
+
+  Halts the Erlang runtime system where the argument `status` must be a
  non-negative integer, the atom `:abort` or a binary.

  * If an integer, the runtime system exits with the integer value which
-    is returned to the Operating System;
+    is returned to the operating system;

  * If `:abort`, the runtime system aborts producing a core dump, if that is
    enabled in the operating system;
@@ -347,9 +385,4 @@ defmodule System do
  def halt(status) when is_binary(status) do
    :erlang.halt(:binary.bin_to_list(status))
  end
-
-  ## Helpers
-
-  defp filter_stacktrace([{ Kernel, :raise, _, _ }|t]), do: t
-  defp filter_stacktrace(t), do: t
 end
@@ -0,0 +1,60 @@
+defmodule Tuple do
+  @moduledoc """
+  Functions for working with tuples.
+  """
+
+  @doc """
+  Create a new tuple.
+
+  Creates a tuple of size `size` containing the
+  given `data` at every position.
+
+  ## Examples
+
+      iex> Tuple.duplicate(:hello, 3)
+      { :hello, :hello, :hello }
+
+  """
+  @spec duplicate(term, non_neg_integer) :: tuple
+  def duplicate(data, size) do
+    :erlang.make_tuple(size, data)
+  end
+
+  @doc """
+  Insert an element into a tuple.
+
+  Inserts `value` into `tuple` at the given zero-based `index`.
+  Raises an `ArgumentError` if `index` is greater than the
+  length of `tuple`.
+
+  ## Examples
+
+      iex> tuple = { :bar, :baz }
+      ...> Tuple.insert_at(tuple, 0, :foo)
+      { :foo, :bar, :baz }
+
+  """
+  @spec insert_at(tuple, non_neg_integer, term) :: tuple
+  def insert_at(tuple, index, term) do
+    :erlang.insert_element(index + 1, tuple, term)
+  end
+
+  @doc """
+  Remove an element from a tuple.
+
+  Deletes the element at the zero-based `index` from `tuple`.
+  Raises an `ArgumentError` if `index` is greater than 
+  or equal to the length of `tuple`.
+
+  ## Examples
+
+      iex> tuple = { :foo, :bar, :baz }
+      ...> Tuple.delete_at(tuple, 0)
+      { :bar, :baz }
+
+  """
+  @spec delete_at(tuple, non_neg_integer) :: tuple
+  def delete_at(tuple, index) do
+    :erlang.delete_element(index + 1, tuple)
+  end
+end
@@ -54,7 +54,7 @@ defmodule URI do
  that implements the `String.Chars` protocol (i.e. can be converted
  to a binary).
  """
-  def encode_query(l), do: Enum.map_join(l, "&", pair(&1))
+  def encode_query(l), do: Enum.map_join(l, "&", &pair/1)

  @doc """
  Given a query string of the form "key1=value1&key=value2...", produces an
@@ -137,6 +137,7 @@ defmodule URI do
  def decode(<<>>), do: <<>>

  defp hex2dec(n) when n in ?A..?F, do: n - ?A + 10
+  defp hex2dec(n) when n in ?a..?f, do: n - ?a + 10
  defp hex2dec(n) when n in ?0..?9, do: n - ?0

  defp check_plus(?+), do: 32
@@ -1,15 +1,13 @@
-defmodule Mix.Version do
+defmodule Version do
  @moduledoc %S"""
-  This module provides functions for parsing and matching
-  versions with requirements.
+  Functions for parsing and matching versions against requirements.

-  A version is a string or a `Mix.Version.Schema` generated
-  after parsing via `Mix.Version.parse/1`. A requirement is
-  a string that follows a specific format.
+  A version is a string in a specific format or a `Version.Schema` 
+  generated after parsing via `Version.parse/1`.

-  `Mix.Version` parsing and requirements follows
+  `Version` parsing and requirements follow
  [SemVer 2.0 schema](http://semver.org/) and you will get
-  the most of Mix' version system by following it. In order
+  the most of Mix's version system by following it. In order
  to support integration with projects that may
  follow different versioning schemas, Elixir won't choke
  on unknown versions, however you won't be able to use
@@ -33,7 +31,7 @@ defmodule Mix.Version do

  Requirements allow you to specify which versions of a given
  dependency you are willing to work against. It supports common
-  operators like `>=`, `<=`, `>`, `==` and friends that would
+  operators like `>=`, `<=`, `>`, `==` and friends that 
  work as one would expect:

      # Only version 2.0.0
@@ -54,8 +52,8 @@ defmodule Mix.Version do

  """

-  @type t :: String.t | Mix.Version.Schema.t
-  @type requirement :: String.t | Mix.Version.Requirement.t
+  @type t :: String.t | Version.Schema.t
+  @type requirement :: String.t | Version.Requirement.t

  @type matchable :: { major :: String.t | non_neg_integer,
                       minor :: non_neg_integer | nil,
@@ -79,11 +77,22 @@ defmodule Mix.Version do
  end

  @doc """
-  Checks if the given version matches the specification.
+  Check if the given version matches the specification.
+
+  Returns `true` if `version` satisfies `requirement`, `false` otherwise.
+  Raises a `Version.InvalidRequirement` exception if `requirement` is not parseable. 
+
+  ## Examples
+
+      iex> Version.match?("2.0", ">1.0")
+      true
+      iex> Version.match?("2.0", "==1.0")
+      false
+
  """
  @spec match?(t, requirement) :: boolean
  def match?(version, requirement) when is_binary(requirement) do
-    case Mix.Version.Parser.parse_requirement(requirement) do
+    case Version.Parser.parse_requirement(requirement) do
      { :ok, req } ->
        match?(version, req)
      { :error, reason } ->
@@ -105,24 +114,38 @@ defmodule Mix.Version do
  end

  @doc """
-  Checks if a version string is compatible with [semver](http://semver.org/).
+  Check if a version string is compatible with [semver](http://semver.org/).
+
+  ## Examples
+
+      iex> Version.valid?("2.0")
+      true
+      iex> Version.valid?("invalid")
+      false
+
  """
  @spec valid?(String.t | Schema.t) :: boolean
  def valid?(string) when is_binary(string) do
-    Mix.Version.Parser.valid_version?(string)
+    Version.Parser.valid_version?(string)
  end

-  def valid?(Mix.Version.Schema[major: nil]), do: false
-  def valid?(Mix.Version.Schema[]),           do: true
+  def valid?(Version.Schema[major: nil]), do: false
+  def valid?(Version.Schema[]),           do: true

  @doc """
-  Parse a version into a matchable value.
+  Parse a version string into a `Version.Schema`.
+
+  ## Examples
+
+      > Version.parse("2.0.1-alpha1")
+      #Version.Schema<2.0.1-alpha1>
+
  """
-  @spec parse(String.t) :: { :ok, Schema.t } | { :error, term }
+  @spec parse(String.t) :: Schema.t
  def parse(string) when is_binary(string) do
-    case Mix.Version.Parser.parse_version(string) do
+    case Version.Parser.parse_version(string) do
      { :ok, matchable } -> from_matchable(matchable).source(string).build(get_build(string))
-      { :error, _ } -> Mix.Version.Schema[source: string]
+      { :error, _ } -> Version.Schema[source: string]
    end
  end

@@ -137,19 +160,25 @@ defmodule Mix.Version do
  end

  @doc """
-  Get the matchable representation.
+  Convert a version to a `Version.matchable`
+
+  ## Examples
+
+      iex> Version.to_matchable("2.0.1-alpha.1")
+      {2, 0, 1, ["alpha", 1]}
+
  """
-  @spec to_matchable(String.t | Schema.t) :: Mix.Version.matchable
+  @spec to_matchable(String.t | Schema.t) :: Version.matchable
  def to_matchable(Schema[major: nil, source: source]) do
    { source, nil, nil, [] }
  end

-  def to_matchable(Mix.Version.Schema[major: major, minor: minor, patch: patch, pre: nil]) do
+  def to_matchable(Version.Schema[major: major, minor: minor, patch: patch, pre: nil]) do
    { major, minor, patch, [] }
  end

-  def to_matchable(Mix.Version.Schema[major: major, minor: minor, patch: patch, pre: pre]) do
-    { major, minor, patch, Mix.Version.Parser.parse_pre(pre) }
+  def to_matchable(Version.Schema[major: major, minor: minor, patch: patch, pre: pre]) do
+    { major, minor, patch, Version.Parser.parse_pre(pre) }
  end

  def to_matchable(string) do
@@ -157,11 +186,17 @@ defmodule Mix.Version do
  end

  @doc """
-  Convert a matchable to a `Mix.Version`.
+  Convert a matchable to a `Version.Schema`.
+
+  ## Examples
+
+      > Version.from_matchable({2, 0, 1, ["alpha", 1]})
+      #Version.Schema<2.0.1-alpha.1>
+
  """
-  @spec from_matchable(Mix.Version.matchable) :: Schema.t
+  @spec from_matchable(Version.matchable) :: Schema.t
  def from_matchable({ source, nil, nil, nil }) when is_binary(source) do
-    Mix.Version.Schema[source: source]
+    Version.Schema[source: source]
  end

  def from_matchable({ major, minor, patch, pre }) do
@@ -184,7 +219,7 @@ defmodule Mix.Version do
      end
    end

-    Mix.Version.Schema[major: major, minor: minor, patch: patch, pre: pre, source: source]
+    Version.Schema[major: major, minor: minor, patch: patch, pre: pre, source: source]
  end

  defmodule Parser.DSL do
@@ -251,12 +286,12 @@ defmodule Mix.Version do
    end

    deflexer acc do
-      Enum.filter(Enum.reverse(acc), &1 != :' ')
+      Enum.filter(Enum.reverse(acc), &(&1 != :' '))
    end

    @version_regex %r/^(\d+)(?:\.(\d+)(?:\.(\d+))?)?(?:\-([^\s]+))?(?:\+[^\d]+)?$/

-    @spec parse_requirement(String.t) :: { :ok, Mix.Version.Requirement.t } | { :error, binary | atom }
+    @spec parse_requirement(String.t) :: { :ok, Version.Requirement.t } | { :error, binary | atom }
    def parse_requirement(source) do
      lexed = lexer(source, [])

@@ -280,7 +315,7 @@ defmodule Mix.Version do
    defp nillify(""), do: nil
    defp nillify(o),  do: o

-    @spec parse_version(String.t) :: { :ok, Mix.Version.matchable } | { :error, :invalid_version }
+    @spec parse_version(String.t) :: { :ok, Version.matchable } | { :error, :invalid_version }
    def parse_version(string) when is_binary(string) do
      if valid_version?(string) do
        destructure [_, major, minor, patch, pre], Regex.run(@version_regex, string)
@@ -364,7 +399,7 @@ defmodule Mix.Version do
    end

    defp approximate(version) do
-      Mix.Version.from_matchable(case Regex.run(@version_regex, version) do
+      Version.from_matchable(case Regex.run(@version_regex, version) do
        [_, major] ->
          { binary_to_integer(major) + 1, 0, 0, [] }

@@ -387,19 +422,19 @@ defmodule Mix.Version do
    end

    defp to_condition([:'==', version | _]) do
-      version = Mix.Version.to_matchable(version)
+      version = Version.to_matchable(version)

      { :'==', :'$_', { :const, version } }
    end

    defp to_condition([:'!=', version | _]) do
-      version = Mix.Version.to_matchable(version)
+      version = Version.to_matchable(version)

      { :'/=', :'$_', { :const, version } }
    end

    defp to_condition([:'~>', version | _]) do
-      from = Mix.Version.parse(version)
+      from = Version.parse(version)
      to   = approximate(version)

      { :andalso, to_condition([:'>=', to_string(from)]),
@@ -407,7 +442,7 @@ defmodule Mix.Version do
    end

    defp to_condition([:'>', version | _]) do
-      { major, minor, patch, pre } = Mix.Version.to_matchable(version)
+      { major, minor, patch, pre } = Version.to_matchable(version)

      { :andalso, { :not, { :is_binary, :'$1' } },
                  { :orelse, { :'>', {{ :'$1', :'$2', :'$3' }},
@@ -423,7 +458,7 @@ defmodule Mix.Version do
    end

    defp to_condition([:'>=', version | _]) do
-      matchable = Mix.Version.to_matchable(version)
+      matchable = Version.to_matchable(version)

      { :orelse, { :andalso, { :not, { :is_binary, :'$1' } },
                             { :'==', :'$_', { :const, matchable } } },
@@ -431,7 +466,7 @@ defmodule Mix.Version do
    end

    defp to_condition([:'<', version | _]) do
-      { major, minor, patch, pre } = Mix.Version.to_matchable(version)
+      { major, minor, patch, pre } = Version.to_matchable(version)

      { :andalso, { :not, { :is_binary, :'$1' } },
                  { :orelse, { :'<', {{ :'$1', :'$2', :'$3' }},
@@ -447,7 +482,7 @@ defmodule Mix.Version do
    end

    defp to_condition([:'<=', version | _]) do
-      matchable = Mix.Version.to_matchable(version)
+      matchable = Version.to_matchable(version)

      { :orelse, { :andalso, { :not, { :is_binary, :'$1' } },
                             { :'==', :'$_', { :const, matchable } } },
@@ -468,26 +503,26 @@ defmodule Mix.Version do
  end
 end

-defimpl String.Chars, for: Mix.Version.Schema do
-  def to_string(Mix.Version.Schema[source: source]) do
+defimpl String.Chars, for: Version.Schema do
+  def to_string(Version.Schema[source: source]) do
    source
  end
 end

-defimpl Inspect, for: Mix.Version.Schema do
+defimpl Inspect, for: Version.Schema do
  def inspect(self, _opts) do
-    "#Mix.Version.Schema<" <> to_string(self) <> ">"
+    "#Version.Schema<" <> to_string(self) <> ">"
  end
 end

-defimpl String.Chars, for: Mix.Version.Requirement do
+defimpl String.Chars, for: Version.Requirement do
  def to_string({ _, source, _ }) do
    source
  end
 end

-defimpl Inspect, for: Mix.Version.Requirement do
+defimpl Inspect, for: Version.Requirement do
  def inspect({ _, source, _ }, _opts) do
-    "#Mix.Version.Requirement<" <> source <> ">"
+    "#Version.Requirement<" <> source <> ">"
  end
 end
@@ -1,420 +0,0 @@
-LATIN CAPITAL LETTER A WITH MACRON AND GRAVE;0100 0300
-LATIN SMALL LETTER A WITH MACRON AND GRAVE;0101 0300
-LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW;0045 0329
-LATIN SMALL LETTER E WITH VERTICAL LINE BELOW;0065 0329
-LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW AND GRAVE;00C8 0329
-LATIN SMALL LETTER E WITH VERTICAL LINE BELOW AND GRAVE;00E8 0329
-LATIN CAPITAL LETTER E WITH VERTICAL LINE BELOW AND ACUTE;00C9 0329
-LATIN SMALL LETTER E WITH VERTICAL LINE BELOW AND ACUTE;00E9 0329
-LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND MACRON;00CA 0304
-LATIN SMALL LETTER E WITH CIRCUMFLEX AND MACRON;00EA 0304
-LATIN CAPITAL LETTER E WITH CIRCUMFLEX AND CARON;00CA 030C
-LATIN SMALL LETTER E WITH CIRCUMFLEX AND CARON;00EA 030C
-LATIN CAPITAL LETTER I WITH MACRON AND GRAVE;012A 0300
-LATIN SMALL LETTER I WITH MACRON AND GRAVE;012B 0300
-LATIN SMALL LETTER I WITH DOT ABOVE AND ACUTE;0069 0307 0301
-LATIN SMALL LETTER NG WITH TILDE ABOVE;006E 0360 0067
-LATIN CAPITAL LETTER O WITH VERTICAL LINE BELOW;004F 0329
-LATIN SMALL LETTER O WITH VERTICAL LINE BELOW;006F 0329
-LATIN CAPITAL LETTER O WITH VERTICAL LINE BELOW AND GRAVE;00D2 0329
-LATIN SMALL LETTER O WITH VERTICAL LINE BELOW AND GRAVE;00F2 0329
-LATIN CAPITAL LETTER O WITH VERTICAL LINE BELOW AND ACUTE;00D3 0329
-LATIN SMALL LETTER O WITH VERTICAL LINE BELOW AND ACUTE;00F3 0329
-LATIN CAPITAL LETTER S WITH VERTICAL LINE BELOW;0053 0329
-LATIN SMALL LETTER S WITH VERTICAL LINE BELOW;0073 0329
-LATIN CAPITAL LETTER U WITH MACRON AND GRAVE;016A 0300
-LATIN SMALL LETTER U WITH MACRON AND GRAVE;016B 0300
-LATIN CAPITAL LETTER A WITH OGONEK AND ACUTE;0104 0301
-LATIN SMALL LETTER A WITH OGONEK AND ACUTE;0105 0301
-LATIN CAPITAL LETTER A WITH OGONEK AND TILDE;0104 0303
-LATIN SMALL LETTER A WITH OGONEK AND TILDE;0105 0303
-LATIN CAPITAL LETTER E WITH OGONEK AND ACUTE;0118 0301
-LATIN SMALL LETTER E WITH OGONEK AND ACUTE;0119 0301
-LATIN CAPITAL LETTER E WITH OGONEK AND TILDE;0118 0303
-LATIN SMALL LETTER E WITH OGONEK AND TILDE;0119 0303
-LATIN CAPITAL LETTER E WITH DOT ABOVE AND ACUTE;0116 0301
-LATIN SMALL LETTER E WITH DOT ABOVE AND ACUTE;0117 0301
-LATIN CAPITAL LETTER E WITH DOT ABOVE AND TILDE;0116 0303
-LATIN SMALL LETTER E WITH DOT ABOVE AND TILDE;0117 0303
-LATIN SMALL LETTER I WITH DOT ABOVE AND GRAVE;0069 0307 0300
-LATIN SMALL LETTER I WITH DOT ABOVE AND TILDE;0069 0307 0303
-LATIN CAPITAL LETTER I WITH OGONEK AND ACUTE;012E 0301
-LATIN SMALL LETTER I WITH OGONEK AND DOT ABOVE AND ACUTE;012F 0307 0301
-LATIN CAPITAL LETTER I WITH OGONEK AND TILDE;012E 0303
-LATIN SMALL LETTER I WITH OGONEK AND DOT ABOVE AND TILDE;012F 0307 0303
-LATIN CAPITAL LETTER J WITH TILDE;004A 0303
-LATIN SMALL LETTER J WITH DOT ABOVE AND TILDE;006A 0307 0303
-LATIN CAPITAL LETTER L WITH TILDE;004C 0303
-LATIN SMALL LETTER L WITH TILDE;006C 0303
-LATIN CAPITAL LETTER M WITH TILDE;004D 0303
-LATIN SMALL LETTER M WITH TILDE;006D 0303
-LATIN CAPITAL LETTER R WITH TILDE;0052 0303
-LATIN SMALL LETTER R WITH TILDE;0072 0303
-LATIN CAPITAL LETTER U WITH OGONEK AND ACUTE;0172 0301
-LATIN SMALL LETTER U WITH OGONEK AND ACUTE;0173 0301
-LATIN CAPITAL LETTER U WITH OGONEK AND TILDE;0172 0303
-LATIN SMALL LETTER U WITH OGONEK AND TILDE;0173 0303
-LATIN CAPITAL LETTER U WITH MACRON AND ACUTE;016A 0301
-LATIN SMALL LETTER U WITH MACRON AND ACUTE;016B 0301
-LATIN CAPITAL LETTER U WITH MACRON AND TILDE;016A 0303
-LATIN SMALL LETTER U WITH MACRON AND TILDE;016B 0303
-LATIN SMALL LETTER AE WITH GRAVE;00E6 0300
-LATIN SMALL LETTER OPEN O WITH GRAVE;0254 0300
-LATIN SMALL LETTER OPEN O WITH ACUTE;0254 0301
-LATIN SMALL LETTER TURNED V WITH GRAVE;028C 0300
-LATIN SMALL LETTER TURNED V WITH ACUTE;028C 0301
-LATIN SMALL LETTER SCHWA WITH GRAVE;0259 0300
-LATIN SMALL LETTER SCHWA WITH ACUTE;0259 0301
-LATIN SMALL LETTER HOOKED SCHWA WITH GRAVE;025A 0300
-LATIN SMALL LETTER HOOKED SCHWA WITH ACUTE;025A 0301
-BENGALI LETTER KHINYA;0995 09CD 09B7
-TAMIL CONSONANT K;  0B95 0BCD
-TAMIL CONSONANT NG; 0B99 0BCD
-TAMIL CONSONANT C;  0B9A 0BCD
-TAMIL CONSONANT NY; 0B9E 0BCD
-TAMIL CONSONANT TT; 0B9F 0BCD
-TAMIL CONSONANT NN; 0BA3 0BCD
-TAMIL CONSONANT T;  0BA4 0BCD
-TAMIL CONSONANT N;  0BA8 0BCD
-TAMIL CONSONANT P;  0BAA 0BCD
-TAMIL CONSONANT M;  0BAE 0BCD
-TAMIL CONSONANT Y;  0BAF 0BCD
-TAMIL CONSONANT R;  0BB0 0BCD
-TAMIL CONSONANT L;  0BB2 0BCD
-TAMIL CONSONANT V;  0BB5 0BCD
-TAMIL CONSONANT LLL;0BB4 0BCD
-TAMIL CONSONANT LL; 0BB3 0BCD
-TAMIL CONSONANT RR; 0BB1 0BCD
-TAMIL CONSONANT NNN;0BA9 0BCD
-TAMIL CONSONANT J;  0B9C 0BCD
-TAMIL CONSONANT SH; 0BB6 0BCD
-TAMIL CONSONANT SS; 0BB7 0BCD
-TAMIL CONSONANT S;  0BB8 0BCD
-TAMIL CONSONANT H;  0BB9 0BCD
-TAMIL CONSONANT KSS;0B95 0BCD 0BB7 0BCD
-TAMIL SYLLABLE KAA; 0B95 0BBE
-TAMIL SYLLABLE KI;  0B95 0BBF
-TAMIL SYLLABLE KII; 0B95 0BC0
-TAMIL SYLLABLE KU;  0B95 0BC1
-TAMIL SYLLABLE KUU; 0B95 0BC2
-TAMIL SYLLABLE KE;  0B95 0BC6
-TAMIL SYLLABLE KEE; 0B95 0BC7
-TAMIL SYLLABLE KAI; 0B95 0BC8
-TAMIL SYLLABLE KO;  0B95 0BCA
-TAMIL SYLLABLE KOO; 0B95 0BCB
-TAMIL SYLLABLE KAU; 0B95 0BCC
-TAMIL SYLLABLE NGAA; 0B99 0BBE
-TAMIL SYLLABLE NGI;  0B99 0BBF
-TAMIL SYLLABLE NGII; 0B99 0BC0
-TAMIL SYLLABLE NGU;  0B99 0BC1
-TAMIL SYLLABLE NGUU; 0B99 0BC2
-TAMIL SYLLABLE NGE;  0B99 0BC6
-TAMIL SYLLABLE NGEE; 0B99 0BC7
-TAMIL SYLLABLE NGAI; 0B99 0BC8
-TAMIL SYLLABLE NGO;  0B99 0BCA
-TAMIL SYLLABLE NGOO; 0B99 0BCB
-TAMIL SYLLABLE NGAU; 0B99 0BCC
-TAMIL SYLLABLE CI;  0B9A 0BBF
-TAMIL SYLLABLE CII; 0B9A 0BC0
-TAMIL SYLLABLE CU;  0B9A 0BC1
-TAMIL SYLLABLE CUU; 0B9A 0BC2
-TAMIL SYLLABLE CE;  0B9A 0BC6
-TAMIL SYLLABLE CEE; 0B9A 0BC7
-TAMIL SYLLABLE CAI; 0B9A 0BC8
-TAMIL SYLLABLE CO;  0B9A 0BCA
-TAMIL SYLLABLE COO; 0B9A 0BCB
-TAMIL SYLLABLE CAU; 0B9A 0BCC
-TAMIL SYLLABLE NYAA; 0B9E 0BBE
-TAMIL SYLLABLE NYI;  0B9E 0BBF
-TAMIL SYLLABLE NYII; 0B9E 0BC0
-TAMIL SYLLABLE NYU;  0B9E 0BC1
-TAMIL SYLLABLE NYUU; 0B9E 0BC2
-TAMIL SYLLABLE NYE;  0B9E 0BC6
-TAMIL SYLLABLE NYEE; 0B9E 0BC7
-TAMIL SYLLABLE NYAI; 0B9E 0BC8
-TAMIL SYLLABLE NYO;  0B9E 0BCA
-TAMIL SYLLABLE NYOO; 0B9E 0BCB
-TAMIL SYLLABLE NYAU; 0B9E 0BCC
-TAMIL SYLLABLE TTAA; 0B9F 0BBE
-TAMIL SYLLABLE TTI;  0B9F 0BBF
-TAMIL SYLLABLE TTII; 0B9F 0BC0
-TAMIL SYLLABLE TTU;  0B9F 0BC1
-TAMIL SYLLABLE TTUU; 0B9F 0BC2
-TAMIL SYLLABLE TTE;  0B9F 0BC6
-TAMIL SYLLABLE TTEE; 0B9F 0BC7
-TAMIL SYLLABLE TTAI; 0B9F 0BC8
-TAMIL SYLLABLE TTO;  0B9F 0BCA
-TAMIL SYLLABLE TTOO; 0B9F 0BCB
-TAMIL SYLLABLE TTAU; 0B9F 0BCC
-TAMIL SYLLABLE NNAA; 0BA3 0BBE
-TAMIL SYLLABLE NNI;  0BA3 0BBF
-TAMIL SYLLABLE NNII; 0BA3 0BC0
-TAMIL SYLLABLE NNU;  0BA3 0BC1
-TAMIL SYLLABLE NNUU; 0BA3 0BC2
-TAMIL SYLLABLE NNE;  0BA3 0BC6
-TAMIL SYLLABLE NNEE; 0BA3 0BC7
-TAMIL SYLLABLE NNAI; 0BA3 0BC8
-TAMIL SYLLABLE NNO;  0BA3 0BCA
-TAMIL SYLLABLE NNOO; 0BA3 0BCB
-TAMIL SYLLABLE NNAU; 0BA3 0BCC
-TAMIL SYLLABLE TAA; 0BA4 0BBE
-TAMIL SYLLABLE TI;  0BA4 0BBF
-TAMIL SYLLABLE TII; 0BA4 0BC0
-TAMIL SYLLABLE TU;  0BA4 0BC1
-TAMIL SYLLABLE TUU; 0BA4 0BC2
-TAMIL SYLLABLE TE;  0BA4 0BC6
-TAMIL SYLLABLE TEE; 0BA4 0BC7
-TAMIL SYLLABLE TAI; 0BA4 0BC8
-TAMIL SYLLABLE TO;  0BA4 0BCA
-TAMIL SYLLABLE TOO; 0BA4 0BCB
-TAMIL SYLLABLE TAU; 0BA4 0BCC
-TAMIL SYLLABLE NAA; 0BA8 0BBE
-TAMIL SYLLABLE NI;  0BA8 0BBF
-TAMIL SYLLABLE NII; 0BA8 0BC0
-TAMIL SYLLABLE NU;  0BA8 0BC1
-TAMIL SYLLABLE NUU; 0BA8 0BC2
-TAMIL SYLLABLE NE;  0BA8 0BC6
-TAMIL SYLLABLE NEE; 0BA8 0BC7
-TAMIL SYLLABLE NAI; 0BA8 0BC8
-TAMIL SYLLABLE NO;  0BA8 0BCA
-TAMIL SYLLABLE NOO; 0BA8 0BCB
-TAMIL SYLLABLE NAU; 0BA8 0BCC
-TAMIL SYLLABLE PAA; 0BAA 0BBE
-TAMIL SYLLABLE PI;  0BAA 0BBF
-TAMIL SYLLABLE PII; 0BAA 0BC0
-TAMIL SYLLABLE PU;  0BAA 0BC1
-TAMIL SYLLABLE PUU; 0BAA 0BC2
-TAMIL SYLLABLE PE;  0BAA 0BC6
-TAMIL SYLLABLE PEE; 0BAA 0BC7
-TAMIL SYLLABLE PAI; 0BAA 0BC8
-TAMIL SYLLABLE PO;  0BAA 0BCA
-TAMIL SYLLABLE POO; 0BAA 0BCB
-TAMIL SYLLABLE PAU; 0BAA 0BCC
-TAMIL SYLLABLE MAA; 0BAE 0BBE
-TAMIL SYLLABLE MI;  0BAE 0BBF
-TAMIL SYLLABLE MII; 0BAE 0BC0
-TAMIL SYLLABLE MU;  0BAE 0BC1
-TAMIL SYLLABLE MUU; 0BAE 0BC2
-TAMIL SYLLABLE ME;  0BAE 0BC6
-TAMIL SYLLABLE MEE; 0BAE 0BC7
-TAMIL SYLLABLE MAI; 0BAE 0BC8
-TAMIL SYLLABLE MO;  0BAE 0BCA
-TAMIL SYLLABLE MOO; 0BAE 0BCB
-TAMIL SYLLABLE MAU; 0BAE 0BCC
-TAMIL SYLLABLE YAA; 0BAF 0BBE
-TAMIL SYLLABLE YI;  0BAF 0BBF
-TAMIL SYLLABLE YII; 0BAF 0BC0
-TAMIL SYLLABLE YU;  0BAF 0BC1
-TAMIL SYLLABLE YUU; 0BAF 0BC2
-TAMIL SYLLABLE YE;  0BAF 0BC6
-TAMIL SYLLABLE YEE; 0BAF 0BC7
-TAMIL SYLLABLE YAI; 0BAF 0BC8
-TAMIL SYLLABLE YO;  0BAF 0BCA
-TAMIL SYLLABLE YOO; 0BAF 0BCB
-TAMIL SYLLABLE YAU; 0BAF 0BCC
-TAMIL SYLLABLE RAA; 0BB0 0BBE
-TAMIL SYLLABLE RI;  0BB0 0BBF
-TAMIL SYLLABLE RII; 0BB0 0BC0
-TAMIL SYLLABLE RU;  0BB0 0BC1
-TAMIL SYLLABLE RUU; 0BB0 0BC2
-TAMIL SYLLABLE RE;  0BB0 0BC6
-TAMIL SYLLABLE REE; 0BB0 0BC7
-TAMIL SYLLABLE RAI; 0BB0 0BC8
-TAMIL SYLLABLE RO;  0BB0 0BCA
-TAMIL SYLLABLE ROO; 0BB0 0BCB
-TAMIL SYLLABLE RAU; 0BB0 0BCC
-TAMIL SYLLABLE LAA; 0BB2 0BBE
-TAMIL SYLLABLE LI;  0BB2 0BBF
-TAMIL SYLLABLE LII; 0BB2 0BC0
-TAMIL SYLLABLE LU;  0BB2 0BC1
-TAMIL SYLLABLE LUU; 0BB2 0BC2
-TAMIL SYLLABLE LE;  0BB2 0BC6
-TAMIL SYLLABLE LEE; 0BB2 0BC7
-TAMIL SYLLABLE LAI; 0BB2 0BC8
-TAMIL SYLLABLE LO;  0BB2 0BCA
-TAMIL SYLLABLE LOO; 0BB2 0BCB
-TAMIL SYLLABLE LAU; 0BB2 0BCC
-TAMIL SYLLABLE VAA; 0BB5 0BBE
-TAMIL SYLLABLE VI;  0BB5 0BBF
-TAMIL SYLLABLE VII; 0BB5 0BC0
-TAMIL SYLLABLE VU;  0BB5 0BC1
-TAMIL SYLLABLE VUU; 0BB5 0BC2
-TAMIL SYLLABLE VE;  0BB5 0BC6
-TAMIL SYLLABLE VEE; 0BB5 0BC7
-TAMIL SYLLABLE VAI; 0BB5 0BC8
-TAMIL SYLLABLE VO;  0BB5 0BCA
-TAMIL SYLLABLE VOO; 0BB5 0BCB
-TAMIL SYLLABLE VAU; 0BB5 0BCC
-TAMIL SYLLABLE LLLAA; 0BB4 0BBE
-TAMIL SYLLABLE LLLI;  0BB4 0BBF
-TAMIL SYLLABLE LLLII; 0BB4 0BC0
-TAMIL SYLLABLE LLLU;  0BB4 0BC1
-TAMIL SYLLABLE LLLUU; 0BB4 0BC2
-TAMIL SYLLABLE LLLE;  0BB4 0BC6
-TAMIL SYLLABLE LLLEE; 0BB4 0BC7
-TAMIL SYLLABLE LLLAI; 0BB4 0BC8
-TAMIL SYLLABLE LLLO;  0BB4 0BCA
-TAMIL SYLLABLE LLLOO; 0BB4 0BCB
-TAMIL SYLLABLE LLLAU; 0BB4 0BCC
-TAMIL SYLLABLE LLAA; 0BB3 0BBE
-TAMIL SYLLABLE LLI;  0BB3 0BBF
-TAMIL SYLLABLE LLII; 0BB3 0BC0
-TAMIL SYLLABLE LLU;  0BB3 0BC1
-TAMIL SYLLABLE LLUU; 0BB3 0BC2
-TAMIL SYLLABLE LLE;  0BB3 0BC6
-TAMIL SYLLABLE LLEE; 0BB3 0BC7
-TAMIL SYLLABLE LLAI; 0BB3 0BC8
-TAMIL SYLLABLE LLO;  0BB3 0BCA
-TAMIL SYLLABLE LLOO; 0BB3 0BCB
-TAMIL SYLLABLE LLAU; 0BB3 0BCC
-TAMIL SYLLABLE RRAA; 0BB1 0BBE
-TAMIL SYLLABLE RRI;  0BB1 0BBF
-TAMIL SYLLABLE RRII; 0BB1 0BC0
-TAMIL SYLLABLE RRU;  0BB1 0BC1
-TAMIL SYLLABLE RRUU; 0BB1 0BC2
-TAMIL SYLLABLE RRE;  0BB1 0BC6
-TAMIL SYLLABLE RREE; 0BB1 0BC7
-TAMIL SYLLABLE RRAI; 0BB1 0BC8
-TAMIL SYLLABLE RRO;  0BB1 0BCA
-TAMIL SYLLABLE RROO; 0BB1 0BCB
-TAMIL SYLLABLE RRAU; 0BB1 0BCC
-TAMIL SYLLABLE NNNAA; 0BA9 0BBE
-TAMIL SYLLABLE NNNI;  0BA9 0BBF
-TAMIL SYLLABLE NNNII; 0BA9 0BC0
-TAMIL SYLLABLE NNNU;  0BA9 0BC1
-TAMIL SYLLABLE NNNUU; 0BA9 0BC2
-TAMIL SYLLABLE NNNE;  0BA9 0BC6
-TAMIL SYLLABLE NNNEE; 0BA9 0BC7
-TAMIL SYLLABLE NNNAI; 0BA9 0BC8
-TAMIL SYLLABLE NNNO;  0BA9 0BCA
-TAMIL SYLLABLE NNNOO; 0BA9 0BCB
-TAMIL SYLLABLE NNNAU; 0BA9 0BCC
-TAMIL SYLLABLE JAA; 0B9C 0BBE
-TAMIL SYLLABLE JI;  0B9C 0BBF
-TAMIL SYLLABLE JII; 0B9C 0BC0
-TAMIL SYLLABLE JU;  0B9C 0BC1
-TAMIL SYLLABLE JUU; 0B9C 0BC2
-TAMIL SYLLABLE JE;  0B9C 0BC6
-TAMIL SYLLABLE JEE; 0B9C 0BC7
-TAMIL SYLLABLE JAI; 0B9C 0BC8
-TAMIL SYLLABLE JO;  0B9C 0BCA
-TAMIL SYLLABLE JOO; 0B9C 0BCB
-TAMIL SYLLABLE JAU; 0B9C 0BCC
-TAMIL SYLLABLE SHAA; 0BB6 0BBE
-TAMIL SYLLABLE SHI;  0BB6 0BBF
-TAMIL SYLLABLE SHII; 0BB6 0BC0
-TAMIL SYLLABLE SHU;  0BB6 0BC1
-TAMIL SYLLABLE SHUU; 0BB6 0BC2
-TAMIL SYLLABLE SHE;  0BB6 0BC6
-TAMIL SYLLABLE SHEE; 0BB6 0BC7
-TAMIL SYLLABLE SHAI; 0BB6 0BC8
-TAMIL SYLLABLE SHO;  0BB6 0BCA
-TAMIL SYLLABLE SHOO; 0BB6 0BCB
-TAMIL SYLLABLE SHAU; 0BB6 0BCC
-TAMIL SYLLABLE SSAA; 0BB7 0BBE
-TAMIL SYLLABLE SSI;  0BB7 0BBF
-TAMIL SYLLABLE SSII; 0BB7 0BC0
-TAMIL SYLLABLE SSU;  0BB7 0BC1
-TAMIL SYLLABLE SSUU; 0BB7 0BC2
-TAMIL SYLLABLE SSE;  0BB7 0BC6
-TAMIL SYLLABLE SSEE; 0BB7 0BC7
-TAMIL SYLLABLE SSAI; 0BB7 0BC8
-TAMIL SYLLABLE SSO;  0BB7 0BCA
-TAMIL SYLLABLE SSOO; 0BB7 0BCB
-TAMIL SYLLABLE SSAU; 0BB7 0BCC
-TAMIL SYLLABLE SAA; 0BB8 0BBE
-TAMIL SYLLABLE SI;  0BB8 0BBF
-TAMIL SYLLABLE SII; 0BB8 0BC0
-TAMIL SYLLABLE SU;  0BB8 0BC1
-TAMIL SYLLABLE SUU; 0BB8 0BC2
-TAMIL SYLLABLE SE;  0BB8 0BC6
-TAMIL SYLLABLE SEE; 0BB8 0BC7
-TAMIL SYLLABLE SAI; 0BB8 0BC8
-TAMIL SYLLABLE SO;  0BB8 0BCA
-TAMIL SYLLABLE SOO; 0BB8 0BCB
-TAMIL SYLLABLE SAU; 0BB8 0BCC
-TAMIL SYLLABLE HAA; 0BB9 0BBE
-TAMIL SYLLABLE HI;  0BB9 0BBF
-TAMIL SYLLABLE HII; 0BB9 0BC0
-TAMIL SYLLABLE HU;  0BB9 0BC1
-TAMIL SYLLABLE HUU; 0BB9 0BC2
-TAMIL SYLLABLE HE;  0BB9 0BC6
-TAMIL SYLLABLE HEE; 0BB9 0BC7
-TAMIL SYLLABLE HAI; 0BB9 0BC8
-TAMIL SYLLABLE HO;  0BB9 0BCA
-TAMIL SYLLABLE HOO; 0BB9 0BCB
-TAMIL SYLLABLE HAU; 0BB9 0BCC
-TAMIL SYLLABLE KSSA;  0B95 0BCD 0BB7
-TAMIL SYLLABLE KSSAA; 0B95 0BCD 0BB7 0BBE
-TAMIL SYLLABLE KSSI;  0B95 0BCD 0BB7 0BBF
-TAMIL SYLLABLE KSSII; 0B95 0BCD 0BB7 0BC0
-TAMIL SYLLABLE KSSU;  0B95 0BCD 0BB7 0BC1
-TAMIL SYLLABLE KSSUU; 0B95 0BCD 0BB7 0BC2
-TAMIL SYLLABLE KSSE;  0B95 0BCD 0BB7 0BC6
-TAMIL SYLLABLE KSSEE; 0B95 0BCD 0BB7 0BC7
-TAMIL SYLLABLE KSSAI; 0B95 0BCD 0BB7 0BC8
-TAMIL SYLLABLE KSSO;  0B95 0BCD 0BB7 0BCA
-TAMIL SYLLABLE KSSOO; 0B95 0BCD 0BB7 0BCB
-TAMIL SYLLABLE KSSAU; 0B95 0BCD 0BB7 0BCC
-TAMIL SYLLABLE SHRII; 0BB6 0BCD 0BB0 0BC0
-SINHALA CONSONANT SIGN YANSAYA;0DCA 200D 0DBA
-SINHALA CONSONANT SIGN RAKAARAANSAYA;0DCA 200D 0DBB
-SINHALA CONSONANT SIGN REPAYA;0DBB 0DCA 200D
-GEORGIAN LETTER U-BRJGU;10E3 0302
-KHMER CONSONANT SIGN COENG KA;17D2 1780
-KHMER CONSONANT SIGN COENG KHA;17D2 1781
-KHMER CONSONANT SIGN COENG KO;17D2 1782
-KHMER CONSONANT SIGN COENG KHO;17D2 1783
-KHMER CONSONANT SIGN COENG NGO;17D2 1784
-KHMER CONSONANT SIGN COENG CA;17D2 1785
-KHMER CONSONANT SIGN COENG CHA;17D2 1786
-KHMER CONSONANT SIGN COENG CO;17D2 1787
-KHMER CONSONANT SIGN COENG CHO;17D2 1788
-KHMER CONSONANT SIGN COENG NYO;17D2 1789
-KHMER CONSONANT SIGN COENG DA;17D2 178A
-KHMER CONSONANT SIGN COENG TTHA;17D2 178B
-KHMER CONSONANT SIGN COENG DO;17D2 178C
-KHMER CONSONANT SIGN COENG TTHO;17D2 178D
-KHMER CONSONANT SIGN COENG NA;17D2 178E
-KHMER CONSONANT SIGN COENG TA;17D2 178F
-KHMER CONSONANT SIGN COENG THA;17D2 1790
-KHMER CONSONANT SIGN COENG TO;17D2 1791
-KHMER CONSONANT SIGN COENG THO;17D2 1792
-KHMER CONSONANT SIGN COENG NO;17D2 1793
-KHMER CONSONANT SIGN COENG BA;17D2 1794
-KHMER CONSONANT SIGN COENG PHA;17D2 1795
-KHMER CONSONANT SIGN COENG PO;17D2 1796
-KHMER CONSONANT SIGN COENG PHO;17D2 1797
-KHMER CONSONANT SIGN COENG MO;17D2 1798
-KHMER CONSONANT SIGN COENG YO;17D2 1799
-KHMER CONSONANT SIGN COENG RO;17D2 179A
-KHMER CONSONANT SIGN COENG LO;17D2 179B
-KHMER CONSONANT SIGN COENG VO;17D2 179C
-KHMER CONSONANT SIGN COENG SHA;17D2 179D
-KHMER CONSONANT SIGN COENG SSA;17D2 179E
-KHMER CONSONANT SIGN COENG SA;17D2 179F
-KHMER CONSONANT SIGN COENG HA;17D2 17A0
-KHMER CONSONANT SIGN COENG LA;17D2 17A1
-KHMER VOWEL SIGN COENG QA;17D2 17A2
-KHMER INDEPENDENT VOWEL SIGN COENG QU;17D2 17A7
-KHMER INDEPENDENT VOWEL SIGN COENG RY;17D2 17AB
-KHMER INDEPENDENT VOWEL SIGN COENG RYY;17D2 17AC
-KHMER INDEPENDENT VOWEL SIGN COENG QE;17D2 17AF
-KHMER VOWEL SIGN OM;17BB 17C6
-KHMER VOWEL SIGN AAM;17B6 17C6
-HIRAGANA LETTER BIDAKUON NGA;304B 309A
-HIRAGANA LETTER BIDAKUON NGI;304D 309A
-HIRAGANA LETTER BIDAKUON NGU;304F 309A
-HIRAGANA LETTER BIDAKUON NGE;3051 309A
-HIRAGANA LETTER BIDAKUON NGO;3053 309A
-KATAKANA LETTER BIDAKUON NGA;30AB 309A
-KATAKANA LETTER BIDAKUON NGI;30AD 309A
-KATAKANA LETTER BIDAKUON NGU;30AF 309A
-KATAKANA LETTER BIDAKUON NGE;30B1 309A
-KATAKANA LETTER BIDAKUON NGO;30B3 309A
-KATAKANA LETTER AINU CE;30BB 309A
-KATAKANA LETTER AINU TU;30C4 309A
-KATAKANA LETTER AINU TO;30C8 309A
-KATAKANA LETTER AINU P;31F7 309A
-MODIFIER LETTER EXTRA-HIGH EXTRA-LOW CONTOUR TONE BAR;02E5 02E9
-MODIFIER LETTER EXTRA-LOW EXTRA-HIGH CONTOUR TONE BAR;02E9 02E5
@@ -24,4 +24,4 @@
            {verbose, false}
           ]}.

-{require_otp_vsn,"(R16B).*"}.
+{require_otp_vsn,"(R16B|R17A).*"}.
@@ -2,9 +2,8 @@
 -behaviour(application).
 -export([main/1, start_cli/0,
  scope_for_eval/1, scope_for_eval/2,
-  eval/2, eval/3, eval/4,
-  eval_quoted/2, eval_quoted/3, eval_quoted/4,
-  eval_forms/3, translate_forms/3]).
+  eval/2, eval/3, eval/4, eval_forms/3,
+  eval_quoted/2, eval_quoted/3, eval_quoted/4]).
 -include("elixir.hrl").

 %% Top level types
@@ -124,17 +123,16 @@ eval_quoted(Tree, Binding, Line, #elixir_scope{} = S) when is_integer(Line) ->
 %% Handle forms evaluation internally, it is an
 %% internal API not meant for external usage.

-translate_forms(Tree, Binding, Opts) when is_list(Opts) ->
-  translate_forms(Tree, Binding, scope_for_eval(Opts));
-
-translate_forms(Tree, Binding, #elixir_scope{} = Scope) ->
-  elixir_translator:translate(Tree, elixir_scope:vars_from_binding(Scope, Binding)).
+eval_forms(Tree, Binding, Opts) when is_list(Opts) ->
+  eval_forms(Tree, Binding, scope_for_eval(Opts));

 eval_forms(Tree, Binding, Scope) ->
-  { ParseTree, NewScope } = translate_forms(Tree, Binding, Scope),
-  case ParseTree of
-    [] -> { nil, Binding, NewScope };
+  { ParsedBinding, ParsedScope } = elixir_scope:load_binding(Binding, Scope, nil),
+  { Exprs, NewScope } = elixir_translator:translate(Tree, ParsedScope),
+  case Exprs of
+    [] ->
+      { nil, Binding, NewScope };
    _  ->
-      {value, Value, NewBinding} = erl_eval:exprs(ParseTree, elixir_scope:binding_for_eval(Binding, nil)),
-      {Value, elixir_scope:binding_from_vars(NewScope, NewBinding), NewScope }
+      { value, Value, NewBinding } = erl_eval:exprs(Exprs, ParsedBinding),
+      { Value, elixir_scope:dump_binding(NewBinding, NewScope), NewScope }
  end.
@@ -1,11 +1,13 @@
 -module(elixir_aliases).
 -export([nesting_alias/2, last/1, concat/1, safe_concat/1,
-  format_error/1, ensure_loaded/3, ensure_loaded/4, expand/3, store/4]).
+  format_error/1, ensure_loaded/3, ensure_loaded/4, expand/4, store/5]).
 -include("elixir.hrl").

 %% Store an alias in the given scope
-store(_Meta, New, New, S) -> S;
-store(Meta, New, Old, S) ->
+store(_Meta, New, New, _TKV, S) -> S;
+store(Meta, New, Old, TKV, S) ->
+  record_warn(Meta, New, TKV, S),
+
  SA = S#elixir_scope{
    aliases=orddict:store(New, Old, S#elixir_scope.aliases)
  },
@@ -19,47 +21,58 @@ store(Meta, New, Old, S) ->
      SA
  end.

+record_warn(Meta, Ref, Opts, S) ->
+  Warn =
+    case lists:keyfind(warn, 1, Opts) of
+      { warn, false } -> false;
+      { warn, true } -> true;
+      false -> not lists:keymember(context, 1, Meta)
+    end,
+  elixir_lexical:record_alias(Ref, ?line(Meta), Warn, S#elixir_scope.lexical_tracker).
+
 %% Expand an alias. It returns an atom (meaning that there
 %% was an expansion) or a list of atoms.

-expand({ '__aliases__', Meta, _ } = Alias, Aliases, MacroAliases) ->
+expand({ '__aliases__', Meta, _ } = Alias, Aliases, MacroAliases, LexicalTracker) ->
  case lists:keyfind(alias, 1, Meta) of
    { alias, false } ->
-      expand(Alias, MacroAliases);
+      expand(Alias, MacroAliases, LexicalTracker);
    { alias, Atom } when is_atom(Atom) ->
-      case expand(Alias, MacroAliases) of
+      case expand(Alias, MacroAliases, LexicalTracker) of
        OtherAtom when is_atom(OtherAtom) -> OtherAtom;
        OtherAliases when is_list(OtherAliases) -> Atom
      end;
    false ->
-      expand(Alias, Aliases)
+      expand(Alias, Aliases, LexicalTracker)
  end.

-expand({ '__aliases__', _Meta, [H] }, Aliases) when H /= 'Elixir' ->
-  case expand_one(H, Aliases) of
+expand({ '__aliases__', _Meta, [H] }, Aliases, LexicalTracker) when H /= 'Elixir' ->
+  case expand_one(H, Aliases, LexicalTracker) of
    false -> [H];
    Atom  -> Atom
  end;

-expand({ '__aliases__', _Meta, [H|T] }, Aliases) when is_atom(H) ->
+expand({ '__aliases__', _Meta, [H|T] }, Aliases, LexicalTracker) when is_atom(H) ->
  case H of
    'Elixir' ->
      concat(T);
    _ ->
-      case expand_one(H, Aliases) of
+      case expand_one(H, Aliases, LexicalTracker) of
        false -> [H|T];
        Atom  -> concat([Atom|T])
      end
  end;

-expand({ '__aliases__', _Meta, List }, _Aliases) ->
+expand({ '__aliases__', _Meta, List }, _Aliases, _LexicalTracker) ->
  List.

-expand_one(H, Aliases) ->
+expand_one(H, Aliases, LexicalTracker) ->
  Lookup = list_to_atom("Elixir." ++ atom_to_list(H)),
  case lookup(Lookup, Aliases) of
    Lookup -> false;
-    Else   -> Else
+    Else ->
+      elixir_lexical:record_alias(Lookup, LexicalTracker),
+      Else
  end.

 %% Ensure a module is loaded before its usage.
@@ -4,14 +4,13 @@
  handle_info/2, terminate/2, code_change/3]).
 -behavior(gen_server).
 -record(elixir_code_server, {
+  compilation_status=[],
  argv=[],
-  compilation_status=ok,
  loaded=[],
  at_exit=[],
-  pool=[],
-  counter=0,
+  pool={[],0},
  compiler_options=[{docs,true},{debug_info,true},{warnings_as_errors,false}],
-  waiting=[]
+  erl_compiler_options=nil
 }).

 call(Args) ->
@@ -28,7 +27,9 @@ get_timeout() ->
 start_link() ->
  { ok, _ } = gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).

-init(_args) ->
+init(_Args) ->
+  code:ensure_loaded('Elixir.Module.DispatchTracker'),
+  code:ensure_loaded('Elixir.Kernel.LexicalTracker'),
  { ok, #elixir_code_server{} }.

 handle_call({ acquire, Path }, From, Config) ->
@@ -59,16 +60,27 @@ handle_call(argv, _From, Config) ->
 handle_call(compiler_options, _From, Config) ->
  { reply, Config#elixir_code_server.compiler_options, Config };

-handle_call(compilation_status, _From, Config) ->
-  { reply, Config#elixir_code_server.compilation_status, Config };
+handle_call({ compilation_status, CompilerPid }, _From, Config) ->
+  CompilationStatusList    = Config#elixir_code_server.compilation_status,
+  CompilationStatusListNew = orddict:erase(CompilerPid, CompilationStatusList),
+  CompilationStatus        = orddict:fetch(CompilerPid, CompilationStatusList),
+  { reply, CompilationStatus, Config#elixir_code_server{compilation_status=CompilationStatusListNew} };

 handle_call(retrieve_module_name, _From, Config) ->
  case Config#elixir_code_server.pool of
-    [H|T] ->
-      { reply, module_tuple(H), Config#elixir_code_server{pool=T} };
-    [] ->
-      Counter = Config#elixir_code_server.counter,
-      { reply, module_tuple(Counter), Config#elixir_code_server{counter=Counter+1} }
+    { [H|T], Counter } ->
+      { reply, module_tuple(H), Config#elixir_code_server{pool={T,Counter}} };
+    { [], Counter } ->
+      { reply, module_tuple(Counter), Config#elixir_code_server{pool={[],Counter+1}} }
+  end;
+
+handle_call(erl_compiler_options, _From, Config) ->
+  case Config#elixir_code_server.erl_compiler_options of
+    nil ->
+      Opts = erl_compiler_options(),
+      { reply, Opts, Config#elixir_code_server{erl_compiler_options=Opts} };
+    Opts ->
+      { reply, Opts, Config }
  end;

 handle_call(_Request, _From, Config) ->
@@ -84,14 +96,18 @@ handle_cast({ compiler_options, Options }, Config) ->
  Final = orddict:merge(fun(_,_,V) -> V end, Config#elixir_code_server.compiler_options, Options),
  { noreply, Config#elixir_code_server{compiler_options=Final} };

-handle_cast(register_warning, Config) ->
+handle_cast({ register_warning, CompilerPid }, Config) ->
+  CompilationStatusCurrent = Config#elixir_code_server.compilation_status,
+  CompilationStatusNew     = orddict:store(CompilerPid, error, CompilationStatusCurrent),
  case orddict:find(warnings_as_errors, Config#elixir_code_server.compiler_options) of
-    { ok, true } -> { noreply, Config#elixir_code_server{compilation_status=error} };
+    { ok, true } -> { noreply, Config#elixir_code_server{compilation_status=CompilationStatusNew} };
    _ -> { noreply, Config }
  end;

-handle_cast(reset_warnings, Config) ->
-  { noreply, Config#elixir_code_server{compilation_status=ok} };
+handle_cast({ reset_warnings, CompilerPid }, Config) ->
+  CompilationStatusCurrent = Config#elixir_code_server.compilation_status,
+  CompilationStatusNew     = orddict:store(CompilerPid, ok, CompilationStatusCurrent),
+  { noreply, Config#elixir_code_server{compilation_status=CompilationStatusNew} };

 handle_cast({ loaded, Path }, Config) ->
  Current = Config#elixir_code_server.loaded,
@@ -112,8 +128,8 @@ handle_cast({ unload_files, Files }, Config) ->
  Unloaded = lists:foldl(fun(File, Acc) -> orddict:erase(File, Acc) end, Current, Files),
  { noreply, Config#elixir_code_server{loaded=Unloaded} };

-handle_cast({ return_module_name, I }, #elixir_code_server{pool=Pool} = Config) ->
-  { noreply, Config#elixir_code_server{pool=[I|Pool]} };
+handle_cast({ return_module_name, H }, #elixir_code_server{pool={T,Counter}} = Config) ->
+  { noreply, Config#elixir_code_server{pool={[H|T],Counter}} };

 handle_cast(_Request, Config) ->
  { noreply, Config }.
@@ -127,4 +143,24 @@ terminate(_Reason, _Config) ->
 code_change(_Old, Config, _Extra) ->
  { ok, Config }.

-module_tuple(I) -> { list_to_atom("elixir_compiler_" ++ integer_to_list(I)), I }.
+module_tuple(I) -> { list_to_atom("elixir_compiler_" ++ integer_to_list(I)), I }.
+
+erl_compiler_options() ->
+  Key = "ERL_COMPILER_OPTIONS",
+  case os:getenv(Key) of
+    false -> [];
+    Str when is_list(Str) ->
+      case erl_scan:string(Str) of
+        {ok,Tokens,_} ->
+          case erl_parse:parse_term(Tokens ++ [{dot, 1}]) of
+            {ok,List} when is_list(List) -> List;
+            {ok,Term} -> [Term];
+            {error,_Reason} ->
+              io:format("Ignoring bad term in ~ts\n", [Key]),
+              []
+          end;
+        {error, {_,_,_Reason}, _} ->
+          io:format("Ignoring bad term in ~ts\n", [Key]),
+          []
+      end
+  end.
@@ -1,6 +1,6 @@
 -module(elixir_compiler).
 -export([get_opts/0, get_opt/1, get_opt/2, string/2, quoted/2, file/1, file_to_path/2]).
-export([core/0, module/3, eval_forms/4, format_error/1]).
+-export([core/0, module/4, eval_forms/4, format_error/1]).
 -include("elixir.hrl").

 %% Public API
@@ -18,7 +18,7 @@ get_opt(Key, Dict) ->
 get_opts() ->
  elixir_code_server:call(compiler_options).

-%% Compiles the given string.
+%% Compilation entry points.

 string(Contents, File) when is_list(Contents), is_binary(File) ->
  Forms = elixir_translator:'forms!'(Contents, 1, File, []),
@@ -29,34 +29,34 @@ quoted(Forms, File) when is_binary(File) ->

  try
    put(elixir_compiled, []),
-    eval_forms(Forms, 1, [], elixir:scope_for_eval([{file,File}])),
+    elixir_lexical:run(File, fun
+      (Pid) ->
+        Scope = elixir:scope_for_eval([{file,File}]),
+        eval_forms(Forms, 1, [], Scope#elixir_scope{lexical_tracker=Pid})
+    end),
    lists:reverse(get(elixir_compiled))
  after
    put(elixir_compiled, Previous)
  end.

-%% Compile a file, return a tuple of module names and binaries.
-
 file(Relative) when is_binary(Relative) ->
  File = filename:absname(Relative),
  { ok, Bin } = file:read_file(File),
  string(elixir_utils:characters_to_list(Bin), File).

-%% Compiles a file to the given path (directory).
-
 file_to_path(File, Path) when is_binary(File), is_binary(Path) ->
  Lists = file(File),
  [binary_to_path(X, Path) || X <- Lists],
  Lists.

-%% Evaluates the contents/forms by compiling them to an Erlang module.
+%% Evaluation

 eval_forms(Forms, Line, Vars, S) ->
  { Module, I } = retrieve_module_name(),
  { Exprs, FS } = elixir_translator:translate(Forms, S),

-  Fun  = module_form_fun(S#elixir_scope.module),
-  Form = module_form(Fun, Exprs, Line, S#elixir_scope.file, Module, Vars),
+  Fun  = eval_fun(S#elixir_scope.module),
+  Form = eval_mod(Fun, Exprs, Line, S#elixir_scope.file, Module, Vars),
  Args = [X || { _, _, _, X } <- Vars],

  %% Pass { native, false } to speed up bootstrap
@@ -79,88 +79,10 @@ eval_forms(Forms, Line, Vars, S) ->
    Res
  end), FS }.

-%% Internal API
+eval_fun(nil) -> '__FILE__';
+eval_fun(_)   -> '__MODULE__'.

-%% Compile the module by forms based on the scope information
-%% executes the callback in case of success. This automatically
-%% handles errors and warnings. Used by this module and elixir_module.
-module(Forms, File, Callback) ->
-  Options = case get_opt(debug_info) of
-    true -> [debug_info];
-    _ -> []
-  end,
-  module(Forms, File, Options, false, Callback).
-
-module(Forms, File, RawOptions, Bootstrap, Callback) when
-    is_binary(File), is_list(Forms), is_list(RawOptions), is_boolean(Bootstrap), is_function(Callback) ->
-  { Options, SkipNative } = compile_opts(Forms, RawOptions),
-  Listname = elixir_utils:characters_to_list(File),
-
-  case compile:noenv_forms([no_auto_import()|Forms], [return,{source,Listname}|Options]) of
-    {ok, ModuleName, Binary, RawWarnings} ->
-      Warnings = case SkipNative of
-        true  -> [{?MODULE,[{0,?MODULE,{skip_native,ModuleName}}]}|RawWarnings];
-        false -> RawWarnings
-      end,
-      format_warnings(Bootstrap, Warnings),
-      code:load_binary(ModuleName, Listname, Binary),
-      Callback(ModuleName, Binary);
-    {error, Errors, Warnings} ->
-      format_warnings(Bootstrap, Warnings),
-      format_errors(Errors)
-  end.
-
-%% Compile core files for bootstrap.
-%% Invoked from the Makefile.
-
-core() ->
-  application:start(elixir),
-  elixir_code_server:cast({ compiler_options, [{docs,false},{internal,true}] }),
-  [core_file(File) || File <- core_main()].
-
-%% HELPERS
-
-compile_opts(Forms, Options) ->
-  EnvOptions = env_default_opts(),
-  SkipNative = lists:member(native, EnvOptions) and contains_on_load(Forms),
-  case SkipNative or lists:member([{native,false}], Options) of
-    true  -> { Options ++ lists:delete(native, EnvOptions), SkipNative };
-    false -> { Options ++ EnvOptions, SkipNative }
-  end.
-
-env_default_opts() ->
-  Key = "ERL_COMPILER_OPTIONS",
-  case os:getenv(Key) of
-    false -> [];
-    Str when is_list(Str) ->
-      case erl_scan:string(Str) of
-        {ok,Tokens,_} ->
-          case erl_parse:parse_term(Tokens ++ [{dot, 1}]) of
-            {ok,List} when is_list(List) -> List;
-            {ok,Term} -> [Term];
-            {error,_Reason} ->
-              io:format("Ignoring bad term in ~ts\n", [Key]),
-              []
-          end;
-        {error, {_,_,_Reason}, _} ->
-          io:format("Ignoring bad term in ~ts\n", [Key]),
-          []
-      end
-  end.
-
-contains_on_load([{ attribute, _, on_load, _ }|_]) -> true;
-contains_on_load([_|T]) -> contains_on_load(T);
-contains_on_load([]) -> false.
-
-no_auto_import() ->
-  Bifs = [{ Name, Arity } || { Name, Arity } <- erlang:module_info(exports), erl_internal:bif(Name, Arity)],
-  { attribute, 0, compile, { no_auto_import, Bifs } }.
-
-module_form_fun(nil) -> '__FILE__';
-module_form_fun(_)   -> '__MODULE__'.
-
-module_form(Fun, Exprs, Line, File, Module, Vars) when
-    is_binary(File), is_integer(Line), is_list(Exprs), is_atom(Module) ->
+eval_mod(Fun, Exprs, Line, File, Module, Vars) when is_binary(File), is_integer(Line) ->
  Cons = lists:foldr(fun({ _, _, Var, _ }, Acc) ->
    { cons, Line, { var, Line, Var }, Acc }
  end, { nil, Line }, Vars),
@@ -180,22 +102,68 @@ module_form(Fun, Exprs, Line, File, Module, Vars) when
    ] }
  ].

-%% Generate module names from code server.
-
 retrieve_module_name() ->
  elixir_code_server:call(retrieve_module_name).

 return_module_name(I) ->
  elixir_code_server:cast({ return_module_name, I }).

-%% Receives a module Binary and outputs it in the given path.
+%% INTERNAL API

-binary_to_path({ModuleName, Binary}, CompilePath) ->
-  Path = filename:join(CompilePath, atom_to_list(ModuleName) ++ ".beam"),
-  ok = file:write_file(Path, Binary),
-  Path.
+%% Compile the module by forms based on the scope information
+%% executes the callback in case of success. This automatically
+%% handles errors and warnings. Used by this module and elixir_module.
+module(Forms, File, Opts, Callback) ->
+  Final =
+    case (get_opt(debug_info) == true) orelse
+         lists:member(debug_info, Opts) of
+      true  -> [debug_info];
+      false -> []
+    end,
+  module(Forms, File, Final, false, Callback).

-%% CORE FILES COMPILATION
+module(Forms, File, RawOptions, Bootstrap, Callback) when
+    is_binary(File), is_list(Forms), is_list(RawOptions), is_boolean(Bootstrap), is_function(Callback) ->
+  { Options, SkipNative } = compiler_options(Forms, RawOptions),
+  Listname = elixir_utils:characters_to_list(File),
+
+  case compile:noenv_forms([no_auto_import()|Forms], [return,{source,Listname}|Options]) of
+    {ok, ModuleName, Binary, RawWarnings} ->
+      Warnings = case SkipNative of
+        true  -> [{?MODULE,[{0,?MODULE,{skip_native,ModuleName}}]}|RawWarnings];
+        false -> RawWarnings
+      end,
+      format_warnings(Bootstrap, Warnings),
+      code:load_binary(ModuleName, Listname, Binary),
+      Callback(ModuleName, Binary);
+    {error, Errors, Warnings} ->
+      format_warnings(Bootstrap, Warnings),
+      format_errors(Errors)
+  end.
+
+compiler_options(Forms, Options) ->
+  EnvOptions = elixir_code_server:call(erl_compiler_options),
+  SkipNative = lists:member(native, EnvOptions) and contains_on_load(Forms),
+  case SkipNative or lists:member([{native,false}], Options) of
+    true  -> { Options ++ lists:delete(native, EnvOptions), SkipNative };
+    false -> { Options ++ EnvOptions, SkipNative }
+  end.
+
+contains_on_load([{ attribute, _, on_load, _ }|_]) -> true;
+contains_on_load([_|T]) -> contains_on_load(T);
+contains_on_load([]) -> false.
+
+no_auto_import() ->
+  Bifs = [{ Name, Arity } || { Name, Arity } <- erlang:module_info(exports), erl_internal:bif(Name, Arity)],
+  { attribute, 0, compile, { no_auto_import, Bifs } }.
+
+
+%% CORE HANDLING
+
+core() ->
+  application:start(elixir),
+  elixir_code_server:cast({ compiler_options, [{docs,false},{internal,true}] }),
+  [core_file(File) || File <- core_main()].

 core_file(File) ->
  try
@@ -225,6 +193,7 @@ core_main() ->
    <<"lib/elixir/lib/inspect/algebra.ex">>,
    <<"lib/elixir/lib/inspect.ex">>,
    <<"lib/elixir/lib/range.ex">>,
+    <<"lib/elixir/lib/regex.ex">>,
    <<"lib/elixir/lib/string.ex">>,
    <<"lib/elixir/lib/string/chars.ex">>,
    <<"lib/elixir/lib/io.ex">>,
@@ -234,9 +203,15 @@ core_main() ->
    <<"lib/elixir/lib/kernel/error_handler.ex">>,
    <<"lib/elixir/lib/kernel/parallel_compiler.ex">>,
    <<"lib/elixir/lib/kernel/record_rewriter.ex">>,
+    <<"lib/elixir/lib/kernel/lexical_tracker.ex">>,
    <<"lib/elixir/lib/module/dispatch_tracker.ex">>
  ].

+binary_to_path({ModuleName, Binary}, CompilePath) ->
+  Path = filename:join(CompilePath, atom_to_list(ModuleName) ++ ".beam"),
+  ok = file:write_file(Path, Binary),
+  Path.
+
 %% ERROR HANDLING

 format_error({ skip_native, Module }) ->
@@ -8,9 +8,7 @@
  lookup_definition/2,
  delete_definition/2,
  wrap_definition/6,
-  wrap_definition/8,
  store_definition/7,
-  store_definition/9,
  store_each/8,
  unwrap_stored_definitions/2,
  format_error/1]).
@@ -72,25 +70,17 @@ delete_definition(Module, Tuple) ->
 %% before evaluating the function body), we would see both definitions.

 wrap_definition(Kind, Meta, Call, Expr, CheckClauses, S) ->
-  do_wrap_definition(Kind, Meta, CheckClauses, [
-    Call, Expr, elixir_scope:serialize(S)
+  Line = ?line(Meta),
+  ?wrap_call(Line, ?MODULE, store_definition, [
+    {atom, Line, Kind},
+    {integer, Line, Line},
+    {atom, Line, CheckClauses},
+    {var, Line, '_@MODULE'},
+    Call,
+    Expr,
+    elixir_scope:serialize(S)
  ]).

-wrap_definition(Kind, Meta, Name, Args, Guards, Expr, CheckClauses, S) ->
-  do_wrap_definition(Kind, Meta, CheckClauses, [
-    Name, Args, Guards, Expr, elixir_scope:serialize(S)
-  ]).
-
-do_wrap_definition(Kind, Meta, CheckClauses, Extra) ->
-  Line   = ?line(Meta),
-  Invoke =
-    [{atom, Line, Kind},
-     {integer, Line, Line},
-     {atom, Line, CheckClauses},
-     {var, Line, '_@MODULE'}] ++ Extra,
-
-  ?wrap_call(Line, ?MODULE, store_definition, Invoke).
-
 % Invoked by the wrap definition with the function abstract tree.
 % Each function is then added to the function table.

@@ -139,10 +129,7 @@ store_definition(Kind, Line, CheckClauses, Module, Name, Args, Guards, Body, #el
  [store_each(false, Kind, File, Location, Table, CTable, 0,
    default_function_for(Kind, Name, Default)) || Default <- Defaults],

-  { Name, Arity };
-
-store_definition(Kind, Line, CheckClauses, Module, Name, Args, Guards, Body, RawS) ->
-  store_definition(Kind, Line, CheckClauses, Module, Name, Args, Guards, Body, elixir_scope:deserialize(RawS)).
+  { Name, Arity }.

 %% @on_definition

@@ -1,7 +1,7 @@
 % Holds the logic responsible for defining overridable functions and handling super.
 -module(elixir_def_overridable).
 -export([store_pending/1, is_defined/2, ensure_defined/4,
-  assign_args/3, name/2, store/3, format_error/1]).
+  name/2, store/3, format_error/1]).
 -include("elixir.hrl").

 overridable(Module) ->
@@ -25,19 +25,6 @@ ensure_defined(Meta, Module, Tuple, S) ->
    _    -> elixir_errors:form_error(Meta, S#elixir_scope.file, ?MODULE, { no_super, Module, Tuple })
  end.

-%% Assign pseudo variables to the given vars.
-
-assign_args(Line, Args, S) when is_integer(Line) ->
-  { FArgs, _ } = lists:mapfoldl(fun(X, Acc) -> assign_args(Line, X, Acc, S) end, 1, Args),
-  FArgs.
-
-assign_args(Line, X, Acc, _) ->
-  Match = { match, Line, X, { var, Line, super_arg(Acc) } },
-  { Match, Acc + 1 }.
-
-super_arg(Counter) ->
-  ?atom_concat(['_@S', Counter]).
-
 %% Gets the name based on the function and stored overridables

 name(Module, Function) ->
@@ -24,9 +24,11 @@ find_import(Meta, Name, Arity, S) ->

  case find_dispatch(Meta, Tuple, S) of
    { function, Receiver } ->
+      elixir_lexical:record_import(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_import(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      Receiver;
    { macro, Receiver } ->
+      elixir_lexical:record_import(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_import(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      Receiver;
    _ ->
@@ -39,6 +41,7 @@ import_function(Meta, Name, Arity, S) ->
  Tuple = { Name, Arity },
  case find_dispatch(Meta, Tuple, S) of
    { function, Receiver } ->
+      elixir_lexical:record_import(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_import(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      remote_function(Meta, Receiver, Name, Arity, S);
    { macro, _Receiver } ->
@@ -60,6 +63,7 @@ require_function(Meta, Receiver, Name, Arity, S) ->
  case is_element(Tuple, get_optional_macros(Receiver)) of
    true  -> false;
    false ->
+      elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_remote(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      remote_function(Meta, Receiver, Name, Arity, S)
  end.
@@ -73,6 +77,7 @@ dispatch_import(Meta, Name, Args, S, Callback) ->

  case find_dispatch(Meta, Tuple, S) of
    { function, Receiver } ->
+      elixir_lexical:record_import(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_import(Tuple, Receiver, Module, S#elixir_scope.function),
      Endpoint = case (Receiver == ?builtin) andalso is_element(Tuple, in_erlang_functions()) of
        true  -> erlang;
@@ -80,6 +85,7 @@ dispatch_import(Meta, Name, Args, S, Callback) ->
      end,
      elixir_translator:translate_each({ { '.', Meta, [Endpoint, Name] }, Meta, Args }, S);
    { import, Receiver } ->
+      elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_remote(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      elixir_translator:translate_each({ { '.', Meta, [Receiver, Name] }, [{require,false}|Meta], Args }, S);
    Result ->
@@ -87,10 +93,11 @@ dispatch_import(Meta, Name, Args, S, Callback) ->
        { error, noexpansion } ->
          Callback();
        { error, internal } ->
+          elixir_lexical:record_import(?builtin, S#elixir_scope.lexical_tracker),
          elixir_tracker:record_import(Tuple, ?builtin, Module, S#elixir_scope.function),
          elixir_macros:translate({ Name, Meta, Args }, S);
-        { ok, _Receiver, Tree } ->
-          translate_expansion(Meta, Tree, S)
+        { ok, Receiver, Tree } ->
+          translate_expansion(Meta, Receiver, Tree, S)
      end
  end.

@@ -101,6 +108,7 @@ dispatch_require(Meta, Receiver, Name, Args, S, Callback) ->

  case (Receiver == ?builtin) andalso is_element(Tuple, in_erlang_functions()) of
    true ->
+      elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_remote(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function),
      { TArgs, SA } = elixir_translator:translate_args(Args, S),
      { ?wrap_call(?line(Meta), erlang, Name, TArgs), SA };
@@ -109,10 +117,11 @@ dispatch_require(Meta, Receiver, Name, Args, S, Callback) ->
        { error, noexpansion } ->
          Callback();
        { error, internal } ->
+          elixir_lexical:record_remote(?builtin, S#elixir_scope.lexical_tracker),
          elixir_tracker:record_remote(Tuple, ?builtin, S#elixir_scope.module, S#elixir_scope.function),
          elixir_macros:translate({ Name, Meta, Args }, S);
-        { ok, _Receiver, Tree } ->
-          translate_expansion(Meta, Tree, S)
+        { ok, Receiver, Tree } ->
+          translate_expansion(Meta, Receiver, Tree, S)
      end
  end.

@@ -150,10 +159,12 @@ do_expand_import_no_local(Meta, { Name, Arity } = Tuple, Args, Module, S, Result
      case is_element(Tuple, in_erlang_macros()) of
        true  -> { error, internal };
        false ->
+          elixir_lexical:record_import(?builtin, S#elixir_scope.lexical_tracker),
          elixir_tracker:record_import(Tuple, ?builtin, Module, S#elixir_scope.function),
          { ok, ?builtin, expand_macro_named(Meta, ?builtin, Name, Arity, Args, Module, S) }
      end;
    { macro, Receiver } ->
+      elixir_lexical:record_import(Receiver, S#elixir_scope.lexical_tracker),
      elixir_tracker:record_import(Tuple, Receiver, Module, S#elixir_scope.function),
      { ok, Receiver, expand_macro_named(Meta, Receiver, Name, Arity, Args, Module, S) };
    { import, Receiver } ->
@@ -168,6 +179,7 @@ expand_require(Meta, ?builtin, { Name, Arity } = Tuple, Args, Module, S) ->
    false ->
      case is_element(Tuple, in_elixir_macros()) of
        true  ->
+          elixir_lexical:record_remote(?builtin, S#elixir_scope.lexical_tracker),
          elixir_tracker:record_remote(Tuple, ?builtin, S#elixir_scope.module, S#elixir_scope.function),
          { ok, ?builtin, expand_macro_named(Meta, ?builtin, Name, Arity, Args, Module, S) };
        false ->
@@ -178,20 +190,12 @@ expand_require(Meta, ?builtin, { Name, Arity } = Tuple, Args, Module, S) ->
 expand_require(Meta, Receiver, { Name, Arity } = Tuple, Args, Module, S) ->
  Function = S#elixir_scope.function,

-  Fun = (Module == Receiver) andalso (Function /= nil) andalso
-        (Function /= Tuple) andalso elixir_def_local:macro_for(Tuple, false, S),
-
-  case Fun of
-    false ->
-      case is_element(Tuple, get_optional_macros(Receiver)) of
-        true  ->
-          elixir_tracker:record_remote(Tuple, Receiver, Module, Function),
-          { ok, Receiver, expand_macro_named(Meta, Receiver, Name, Arity, Args, Module, S) };
-        false -> { error, noexpansion }
-      end;
-    _ ->
-      elixir_tracker:record_local(Tuple, Module, Function),
-      { ok, Receiver, expand_macro_fun(Meta, Fun(), Receiver, Name, Args, Module, S) }
+  case is_element(Tuple, get_optional_macros(Receiver)) of
+    true  ->
+      elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
+      elixir_tracker:record_remote(Tuple, Receiver, Module, Function),
+      { ok, Receiver, expand_macro_named(Meta, Receiver, Name, Arity, Args, Module, S) };
+    false -> { error, noexpansion }
  end.

 %% Expansion helpers
@@ -213,7 +217,7 @@ expand_macro_fun(Meta, Fun, Receiver, Name, Args, Module, S) ->
  catch
    Kind:Reason ->
      Info = { Receiver, Name, length(Args), location(Line, S) },
-      erlang:raise(Kind, Reason, munge_stacktrace(Info, erlang:get_stacktrace(), SArg))
+      erlang:raise(Kind, Reason, prune_stacktrace(Info, erlang:get_stacktrace(), SArg))
  end.

 expand_macro_named(Meta, Receiver, Name, Arity, Args, Module, S) ->
@@ -222,17 +226,18 @@ expand_macro_named(Meta, Receiver, Name, Arity, Args, Module, S) ->
  Fun         = fun Receiver:ProperName/ProperArity,
  expand_macro_fun(Meta, Fun, Receiver, Name, Args, Module, S).

-translate_expansion(Meta, Tree, S) ->
+translate_expansion(Meta, Receiver, Tree, S) ->
  Line = ?line(Meta),
+  New  = S#elixir_scope.macro_counter + 1,

  try
    elixir_translator:translate_each(
-      elixir_quote:linify(Line, Tree),
-      S
+      elixir_quote:linify(Line, { Receiver, New }, Tree),
+      S#elixir_scope{macro_counter=New}
    )
  catch
    Kind:Reason ->
-      erlang:raise(Kind, Reason, munge_stacktrace(mfa(Line, S), erlang:get_stacktrace(), nil))
+      erlang:raise(Kind, Reason, prune_stacktrace(mfa(Line, S), erlang:get_stacktrace(), nil))
  end.

 mfa(Line, #elixir_scope{module=nil} = S) ->
@@ -305,17 +310,17 @@ not_an_import(Tuple, Context, Dict) ->
  end.

 %% We've reached the invoked macro, skip it with the rest
-munge_stacktrace(Info, [{ _, _, [S|_], _ }|_], S) ->
+prune_stacktrace(Info, [{ _, _, [S|_], _ }|_], S) ->
  [Info];

 %% We've reached the elixir_dispatch internals, skip it with the rest
-munge_stacktrace(Info, [{ elixir_dispatch, _, _, _ }|_], _) ->
+prune_stacktrace(Info, [{ elixir_dispatch, _, _, _ }|_], _) ->
  [Info];

-munge_stacktrace(Info, [H|T], S) ->
-  [H|munge_stacktrace(Info, T, S)];
+prune_stacktrace(Info, [H|T], S) ->
+  [H|prune_stacktrace(Info, T, S)];

-munge_stacktrace(Info, [], _) ->
+prune_stacktrace(Info, [], _) ->
  [Info].

 remote_function(Meta, Receiver, Name, Arity, S) ->
@@ -336,13 +341,14 @@ remote_function(Meta, Receiver, Name, Arity, S) ->

 %% ERROR HANDLING

-format_error({ unrequired_module, { Receiver, Name, Arity, Required }}) ->
-  String = 'Elixir.Enum':join([elixir_errors:inspect(R) || R <- Required], <<", ">>),
-  io_lib:format("tried to invoke macro ~ts.~ts/~B but module was not required. Required: ~ts",
-    [elixir_errors:inspect(Receiver), Name, Arity, String]);
+format_error({ unrequired_module, { Receiver, Name, Arity, _Required }}) ->
+  Module = elixir_errors:inspect(Receiver),
+  io_lib:format("you must require ~ts before invoking the macro ~ts.~ts/~B",
+    [Module, Module, Name, Arity]);

 format_error({ macro_conflict, { Receiver, Name, Arity } }) ->
-  io_lib:format("call to local macro ~ts/~B conflicts with imported ~ts.~ts/~B",
+  io_lib:format("call to local macro ~ts/~B conflicts with imported ~ts.~ts/~B, "
+    "please rename the local macro or remove the conflicting import",
    [Name, Arity, elixir_errors:inspect(Receiver), Name, Arity]);

 format_error({ ambiguous_call, { Mod1, Mod2, Name, Arity }}) ->
@@ -392,11 +398,10 @@ in_elixir_macros() ->
 in_erlang_functions() ->
  [
    { abs, 1 },
-    { atom_to_binary, 2 },
+    { apply, 2 },
+    { apply, 3 },
    { atom_to_list, 1 },
    { binary_part, 3 },
-    { binary_to_atom, 2 },
-    { binary_to_existing_atom, 2 },
    { binary_to_float, 1 },
    { binary_to_float, 2 },
    { binary_to_integer, 1 },
@@ -440,7 +445,6 @@ in_erlang_functions() ->
    { list_to_float, 1 },
    { list_to_integer, 1 },
    { list_to_integer, 2 },
-    { list_to_pid, 1 },
    { list_to_tuple, 1 },
    { make_ref, 0 },
    { max, 2 },
@@ -448,7 +452,6 @@ in_erlang_functions() ->
    { node, 0 },
    { node, 1 },
    % { now, 0 },
-    { pid_to_list, 1 },
    { round, 1 },
    { self, 0 },
    { size, 1 },
@@ -490,8 +493,6 @@ in_erlang_macros() ->
    {'>=',2},
    {'@',1},
    {'and',2},
-    {apply,2},
-    {apply,3},
    {'case',2},
    {def,1},
    {def,2},
@@ -12,18 +12,25 @@
 -include("elixir.hrl").

 warn(Warning) ->
-  elixir_code_server:cast(register_warning),
+  CompilerPid = get(elixir_compiler_pid),
+
+  if
+    CompilerPid =/= undefined ->
+      elixir_code_server:cast({ register_warning, CompilerPid });
+    true -> false
+  end,
+
  io:put_chars(standard_error, Warning).

-%% Handle inspecting for exceptions
+%% Handle inspecting for exceptions modules

 inspect(Atom) when is_atom(Atom) ->
  'Elixir.Inspect.Atom':inspect(Atom).

 %% Raised during macros translation.

-spec syntax_error(non_neg_integer() | list(), file:filename(), binary() | string()) -> no_return().
-spec syntax_error(non_neg_integer() | list(), file:filename(), binary() | string(), list()) -> no_return().
+-spec syntax_error(non_neg_integer() | list(), file:filename_all(), binary() | string()) -> no_return().
+-spec syntax_error(non_neg_integer() | list(), file:filename_all(), binary() | string(), list()) -> no_return().

 syntax_error(Meta, File, Message) when is_list(Message) ->
  syntax_error(Meta, File, iolist_to_binary(Message));
@@ -47,7 +54,7 @@ compile_error(Meta, File, Format, Args)  ->

 %% Raised on tokenizing/parsing

-spec parse_error(non_neg_integer() | list(), file:filename(), iolist() | atom(), [] | iolist()) -> no_return().
+-spec parse_error(non_neg_integer() | list(), file:filename_all(), iolist() | atom(), [] | iolist()) -> no_return().

 parse_error(Meta, File, Error, []) ->
  Message = case Error of
@@ -75,7 +82,7 @@ parse_error(Meta, File, Error, Token) ->

 %% Raised during compilation

-spec form_error(non_neg_integer() | list(), file:filename(), module(), any()) -> no_return().
+-spec form_error(non_neg_integer() | list(), file:filename_all(), module(), any()) -> no_return().

 form_error(Meta, File, Module, Desc) ->
  Message = iolist_to_binary(format_error(Module, Desc)),
@@ -158,7 +165,7 @@ handle_file_warning(_, File, {Line,Module,Desc}) ->
 handle_file_warning(File, Desc) ->
  handle_file_warning(false, File, Desc).

-spec handle_file_error(file:filename(), {non_neg_integer(), module(), any()}) -> no_return().
+-spec handle_file_error(file:filename_all(), {non_neg_integer(), module(), any()}) -> no_return().

 handle_file_error(File, {Line,erl_lint,{unsafe_var,Var,{In,_Where}}}) ->
  Translated = case In of
@@ -169,6 +176,10 @@ handle_file_error(File, {Line,erl_lint,{unsafe_var,Var,{In,_Where}}}) ->
  Message = io_lib:format("cannot define variable ~ts inside ~ts", [format_var(Var), Translated]),
  raise(Line, File, 'Elixir.CompileError', iolist_to_binary(Message));

+handle_file_error(File, {Line,erl_lint,{spec_fun_undefined,{M,F,A}}}) ->
+  Message = io_lib:format("spec for undefined function ~ts.~ts/~B", [inspect(M), F, A]),
+  raise(Line, File, 'Elixir.CompileError', iolist_to_binary(Message));
+
 handle_file_error(File, {Line,Module,Desc}) ->
  form_error(Line, File, Module, Desc).

@@ -178,18 +189,6 @@ assert_no_function_scope(_Meta, _Kind, #elixir_scope{function=nil}) -> [];
 assert_no_function_scope(Meta, Kind, S) ->
  syntax_error(Meta, S#elixir_scope.file, "cannot invoke ~ts inside a function", [Kind]).

-assert_no_match_or_guard_scope(Meta, Kind, S) ->
-  assert_no_match_scope(Meta, Kind, S),
-  assert_no_guard_scope(Meta, Kind, S).
-
-assert_no_match_scope(Meta, Kind, #elixir_scope{context=match} = S) ->
-  syntax_error(Meta, S#elixir_scope.file, "cannot invoke ~ts inside match clause", [Kind]);
-assert_no_match_scope(_Meta, _Kind, _S) -> [].
-
-assert_no_guard_scope(Meta, Kind, #elixir_scope{context=guard} = S) ->
-  syntax_error(Meta, S#elixir_scope.file, "cannot invoke ~ts inside guard", [Kind]);
-assert_no_guard_scope(_Meta, _Kind, _S) -> [].
-
 assert_module_scope(Meta, Kind, #elixir_scope{module=nil,file=File}) ->
  syntax_error(Meta, File, "cannot invoke ~ts outside module", [Kind]);
 assert_module_scope(_Meta, _Kind, #elixir_scope{module=Module}) -> Module.
@@ -198,6 +197,18 @@ assert_function_scope(Meta, Kind, #elixir_scope{function=nil,file=File}) ->
  syntax_error(Meta, File, "cannot invoke ~ts outside function", [Kind]);
 assert_function_scope(_Meta, _Kind, #elixir_scope{function=Function}) -> Function.

+assert_no_match_or_guard_scope(Meta, Kind, S) ->
+  assert_no_match_scope(Meta, Kind, S),
+  assert_no_guard_scope(Meta, Kind, S).
+
+assert_no_match_scope(Meta, _Kind, #elixir_scope{context=match} = S) ->
+  compile_error(Meta, S#elixir_scope.file, "invalid pattern in match clause", []);
+assert_no_match_scope(_Meta, _Kind, _S) -> [].
+
+assert_no_guard_scope(Meta, _Kind, #elixir_scope{context=guard} = S) ->
+  compile_error(Meta, S#elixir_scope.file, "invalid pattern in guard", []);
+assert_no_guard_scope(_Meta, _Kind, _S) -> [].
+
 %% Helpers

 raise(Meta, File, Kind, Message) when is_list(Meta) ->
@@ -48,6 +48,9 @@ capture(Meta, { { '.', _, [_, Fun] }, _, Args } = Expr, S) when is_atom(Fun), is
 capture(Meta, { { '.', _, [_] }, _, Args } = Expr, S) when is_list(Args) ->
  do_capture(Meta, Expr, S, false);

+capture(Meta, { '__block__', _, [Expr] }, S) ->
+  capture(Meta, Expr, S);
+
 capture(Meta, { '__block__', _, _ } = Expr, S) ->
  Message = "invalid args for &, block expressions are not allowed, got: ~ts",
  syntax_error(Meta, S#elixir_scope.file, Message, ['Elixir.Macro':to_string(Expr)]);
@@ -59,7 +62,7 @@ capture(Meta, { Left, Right }, S) ->
  capture(Meta, { '{}', Meta, [Left, Right] }, S);

 capture(Meta, List, S) when is_list(List) ->
-  capture(Meta, { '[]', Meta, List }, S);
+  do_capture(Meta, List, S, is_sequential_and_not_empty(List));

 capture(Meta, Arg, S) when is_integer(Arg) ->
  compile_error(Meta, S#elixir_scope.file, "unhandled &~B outside of a capture", [Arg]);
@@ -38,15 +38,14 @@ import_macros(Force, Meta, Ref, Opts, S) ->
    S#elixir_scope.macro_macros, Existing, S),
  S#elixir_scope{macros=Macros, macro_macros=Temp}.

-record_warn(_Meta, _Ref, _Opts, #elixir_scope{module=nil}) -> false;
-record_warn(Meta, Ref, Opts, #elixir_scope{module=Module}) ->
+record_warn(Meta, Ref, Opts, S) ->
  Warn =
    case keyfind(warn, Opts) of
      { warn, false } -> false;
      { warn, true } -> true;
      false -> not lists:keymember(context, 1, Meta)
    end,
-  elixir_tracker:record_warn(Ref, Warn, ?line(Meta), Module).
+  elixir_lexical:record_import(Ref, ?line(Meta), Warn, S#elixir_scope.lexical_tracker).

 %% Calculates the imports based on only and except

@@ -202,7 +201,6 @@ special_form('__block__',_) -> true;
 special_form('->',_) -> true;
 special_form('<<>>',_) -> true;
 special_form('{}',_) -> true;
-special_form('[]',_) -> true;
 special_form('alias',1) -> true;
 special_form('alias',2) -> true;
 special_form('require',1) -> true;
@@ -6,62 +6,70 @@ unescape_tokens/1, unescape_tokens/2, unescape_map/1]).

 %% Extract string interpolations

-extract(Line, File, Interpol, String, Last) ->
-  extract(Line, File, Interpol, String, [], [], [], Last).
+extract(Line, Raw, Interpol, String, Last) ->
+  %% Ignore whatever is in the scope and enable terminator checking.
+  Scope = Raw#elixir_tokenizer{terminators=[], check_terminators=true},
+  extract(Line, Scope, Interpol, String, [], 0, [], Last).

-extract(Line, File, _Interpol, [], Buffer, [], Output, []) ->
-  finish_extraction(Line, File, Buffer, Output, []);
+%% Terminators

-extract(Line, _File, _Interpol, [], _Buffer, [], _Output, Last) ->
-  { error, { Line, io_lib:format("missing terminator: ~ts", [[Last]]), [] } };
+extract(Line, _Scope, _Interpol, [], Buffer, 0, Output, []) ->
+  finish_extraction(Line, Buffer, Output, []);

-extract(Line, File, _Interpol, [Last|Remaining], Buffer, [], Output, Last) ->
-  finish_extraction(Line, File, Buffer, Output, Remaining);
+extract(Line, _Scope, _Interpol, [], _Buffer, 0, _Output, Last) ->
+  { error, { string, Line, io_lib:format("missing terminator: ~ts", [[Last]]), [] } };

-extract(Line, _File, _Interpol, End, _Buffer, _Search, _Output, Last) when End == [Last]; End == [] ->
-  { error, { Line, io_lib:format("missing terminator: ~ts", [[Last]]), [] } };
+extract(Line, _Scope, _Interpol, [Last|Remaining], Buffer, 0, Output, Last) ->
+  finish_extraction(Line, Buffer, Output, Remaining);

-extract(Line, File, Interpol, [$\n|Rest], Buffer, Search, Output, Last) ->
-  extract(Line+1, File, Interpol, Rest, [$\n|Buffer], Search, Output, Last);
+extract(Line, _Scope, _Interpol, [], _Buffer, _Search, _Output, Last) ->
+  { error, { string, Line, io_lib:format("missing terminator: ~ts", [[Last]]), [] } };

-extract(Line, File, Interpol, [$\\, $#, ${|Rest], Buffer, [], Output, Last) ->
-  extract(Line, File, Interpol, Rest, [${,$#|Buffer], [], Output, Last);
+%% Going through the string

-extract(Line, File, Interpol, [$\\,Char|Rest], Buffer, [], Output, Last) ->
-  extract(Line, File, Interpol, Rest, [Char,$\\|Buffer], [], Output, Last);
+extract(Line, Scope, Interpol, [$\n|Rest], Buffer, Search, Output, Last) ->
+  extract(Line+1, Scope, Interpol, Rest, [$\n|Buffer], Search, Output, Last);

-extract(Line, File, true, [$#, ${|Rest], Buffer, [], Output, Last) ->
-  NewOutput = build_interpol(s, Line, File, Buffer, Output),
-  extract(Line, File, true, Rest, [], [$}], NewOutput, Last);
+extract(Line, Scope, Interpol, [$\\, $#, ${|Rest], Buffer, Search, Output, Last) ->
+  extract(Line, Scope, Interpol, Rest, [${,$#|Buffer], Search, Output, Last);

-extract(Line, File, true, [$}|Rest], Buffer, [$}], Output, Last) ->
-  NewOutput = build_interpol(i, Line, File, Buffer, Output),
-  extract(Line, File, true, Rest, [], [], NewOutput, Last);
+extract(Line, Scope, Interpol, [$\\,Char|Rest], Buffer, Search, Output, Last) ->
+  extract(Line, Scope, Interpol, Rest, [Char,$\\|Buffer], Search, Output, Last);

-%% Check for available separators inside interpolation
+extract(Line, Scope, true, [$#, ${|Rest], Buffer, Search, Output, Last) ->
+  Output1 = build_string(Line, Buffer, Output),

-extract(Line, File, Interpol, [C|Rest], Buffer, [C|Search], Output, Last) when C == $); C == $]; C == $}; C == $>; C == $"; C == $' ->
-  extract(Line, File, Interpol, Rest, [C|Buffer], Search, Output, Last);
+  case elixir_tokenizer:tokenize(Rest, Line, Scope) of
+    { error, { EndLine, _, "}" }, [$}|NewRest], Tokens } ->
+      Output2 = build_interpol(Line, Tokens, Output1),
+      extract(EndLine, Scope, true, NewRest, [], Search, Output2, Last);
+    { error, Reason, _, _ } ->
+      { error, Reason };
+    { ok, _EndLine, _ } ->
+      { error, { string, Line, "missing interpolation terminator: }", [] } }
+  end;

-extract(Line, File, Interpol, [C|Rest], Buffer, [_|_] = Search, Output, Last) when C == $"; C == $' ->
-  extract(Line, File, Interpol, Rest, [C|Buffer], [C|Search], Output, Last);
+%% Matching () [] {} <> inside sigils

-extract(Line, File, Interpol, [$<|Rest], Buffer, [_|_] = Search, Output, Last) ->
-  extract(Line, File, Interpol, Rest, [$<|Buffer], [$>|Search], Output, Last);
+extract(Line, Scope, Interpol, [$(|Rest], Buffer, Search, Output, $)) ->
+  extract(Line, Scope, Interpol, Rest, [$(|Buffer], Search + 1, Output, $));

-extract(Line, File, Interpol, [${|Rest], Buffer, [_|_] = Search, Output, Last) ->
-  extract(Line, File, Interpol, Rest, [${|Buffer], [$}|Search], Output, Last);
+extract(Line, Scope, Interpol, [$[|Rest], Buffer, Search, Output, $]) ->
+  extract(Line, Scope, Interpol, Rest, [$[|Buffer], Search + 1, Output, $]);

-extract(Line, File, Interpol, [$[|Rest], Buffer, [_|_] = Search, Output, Last) ->
-  extract(Line, File, Interpol, Rest, [$[|Buffer], [$]|Search], Output, Last);
+extract(Line, Scope, Interpol, [${|Rest], Buffer, Search, Output, $}) ->
+  extract(Line, Scope, Interpol, Rest, [${|Buffer], Search + 1, Output, $});

-extract(Line, File, Interpol, [$(|Rest], Buffer, [_|_] = Search, Output, Last) ->
-  extract(Line, File, Interpol, Rest, [$(|Buffer], [$)|Search], Output, Last);
+extract(Line, Scope, Interpol, [$<|Rest], Buffer, Search, Output, $>) ->
+  extract(Line, Scope, Interpol, Rest, [$<|Buffer], Search + 1, Output, $>);

-%% Else
+extract(Line, Scope, Interpol, [Last|Rest], Buffer, Search, Output, Last) ->
+  extract(Line, Scope, Interpol, Rest, [Last|Buffer], Search - 1, Output, Last);

-extract(Line, File, Interpol, [Char|Rest], Buffer, Search, Output, Last) ->
-  extract(Line, File, Interpol, Rest, [Char|Buffer], Search, Output, Last).
+%% Catch all clause
+
+extract(Line, Scope, Interpol, [Char|Rest], Buffer, Search, Output, Last) ->
+  extract(Line, Scope, Interpol, Rest, [Char|Buffer], Search, Output, Last).

 %% Unescape a series of tokens as returned by extract.

@@ -148,30 +156,16 @@ unescape_map(E)  -> E.

 % Extract Helpers

-finish_extraction(Line, File, Buffer, Output, Remaining) ->
-  case build_interpol(s, Line, File, Buffer, Output) of
+finish_extraction(Line, Buffer, Output, Remaining) ->
+  case build_string(Line, Buffer, Output) of
    []    -> Final = [<<>>];
    Final -> []
  end,
  { Line, lists:reverse(Final), Remaining }.

-build_interpol(_Kind, _Line, _File, [], Output) ->
-  Output;
+build_string(_Line, [], Output) -> Output;
+build_string(_Line, Buffer, Output) ->
+  [elixir_utils:characters_to_binary(lists:reverse(Buffer))|Output].

-build_interpol(s, _Line, _File, Buffer, Output) ->
-  [elixir_utils:characters_to_binary(lists:reverse(Buffer))|Output];
-
-build_interpol(i, Line, File, Buffer, Output) ->
-  [wrap_interpol(Line, forms(lists:reverse(Buffer), Line, File))| Output].
-
-wrap_interpol(Line, Form) ->
-  Meta = [{line,Line}],
-  { '::', Meta, [{ { '.', Meta, ['Elixir.Kernel', to_string] }, Meta, [Form]}, { binary, Meta, nil }]}.
-
-forms(String, StartLine, File) ->
-  case elixir_translator:forms(String, StartLine, File, []) of
-    { ok, [] } -> nil;
-    { ok, [Forms] } when not is_list(Forms) -> Forms;
-    { ok, Forms } -> { '__block__', [{line,StartLine}], Forms };
-    { error, Tuple } -> throw({ interpolation_error, Tuple })
-  end.
+build_interpol(Line, Buffer, Output) ->
+  [{ Line, lists:reverse(Buffer) }|Output].
@@ -0,0 +1,80 @@
+%% Module responsible for tracking lexical information.
+-module(elixir_lexical).
+-export([run/2,
+  record_alias/4, record_alias/2,
+  record_import/4, record_import/2,
+  record_remote/2, format_error/1
+]).
+-include("elixir.hrl").
+
+-define(tracker, 'Elixir.Kernel.LexicalTracker').
+
+run(File, Callback) ->
+  case code:is_loaded(?tracker) of
+    { file, _ } ->
+      Pid = ?tracker:start_link(),
+
+      try
+        Callback(Pid)
+      after
+        warn_unused_aliases(File, Pid),
+        warn_unused_imports(File, Pid),
+        unlink(Pid), ?tracker:stop(Pid)
+      end;
+    false ->
+      Callback(nil)
+  end.
+
+%% RECORD
+
+record_alias(Module, Line, Warn, Ref) ->
+  if_tracker(Ref, fun(Pid) ->
+    ?tracker:add_alias(Pid, Module, Line, Warn),
+    true
+  end).
+
+record_import(Module, Line, Warn, Ref) ->
+  if_tracker(Ref, fun(Pid) ->
+    ?tracker:add_import(Pid, Module, Line, Warn),
+    true
+  end).
+
+record_alias(Module, Ref) ->
+  if_tracker(Ref, fun(Pid) ->
+    ?tracker:alias_dispatch(Pid, Module),
+    true
+  end).
+
+record_import(Module, Ref) ->
+  if_tracker(Ref, fun(Pid) ->
+    ?tracker:import_dispatch(Pid, Module),
+    true
+  end).
+
+record_remote(Module, Ref) ->
+  if_tracker(Ref, fun(Pid) ->
+    ?tracker:remote_dispatch(Pid, Module),
+    true
+  end).
+
+%% HELPERS
+
+if_tracker(nil, _Callback) -> false;
+if_tracker(Pid, Callback) when is_pid(Pid) -> Callback(Pid).
+
+%% ERROR HANDLING
+
+warn_unused_imports(File, Pid) ->
+  [ begin
+      elixir_errors:handle_file_warning(File, { L, ?MODULE, { unused_import, M } })
+    end || { M, L } <- ?tracker:collect_unused_imports(Pid)].
+
+warn_unused_aliases(File, Pid) ->
+  [ begin
+      elixir_errors:handle_file_warning(File, { L, ?MODULE, { unused_alias, M } })
+    end || { M, L } <- ?tracker:collect_unused_aliases(Pid)].
+
+format_error({unused_alias, Module}) ->
+  io_lib:format("unused alias ~ts", [elixir_errors:inspect(Module)]);
+format_error({unused_import, Module}) ->
+  io_lib:format("unused import ~ts", [elixir_errors:inspect(Module)]).
@@ -5,55 +5,40 @@
 -import(elixir_scope, [umergec/2]).
 -include("elixir.hrl").

-translate({ '<<>>', Meta, Args } = Original, S) when is_list(Args) ->
-  case elixir_partials:handle(Original, S, allow_tail) of
-    error ->
-      case S#elixir_scope.context of
-        match ->
-          build_bitstr(fun elixir_translator:translate_each/2, Args, Meta, S);
-        _ ->
-          { TArgs, { SC, SV } } = build_bitstr(fun elixir_translator:translate_arg/2, Args, Meta, { S, S }),
-          { TArgs, umergec(SV, SC) }
-      end;
-    Else -> Else
+translate({ '<<>>', Meta, Args }, S) when is_list(Args) ->
+  case S#elixir_scope.context of
+    match ->
+      build_bitstr(fun elixir_translator:translate_each/2, Args, Meta, S);
+    _ ->
+      { TArgs, { SC, SV } } = build_bitstr(fun elixir_translator:translate_arg/2, Args, Meta, { S, S }),
+      { TArgs, umergec(SV, SC) }
  end;

-translate({ '{}', Meta, Args } = Original, S) when is_list(Args) ->
-  case elixir_partials:handle(Original, S) of
-    error ->
-      { TArgs, SE } = translate_args(Args, S),
-      { { tuple, ?line(Meta), TArgs }, SE };
-    Else -> Else
-  end;
-
-translate({ '[]', _Meta, [] }, S) ->
-  { { nil, 0 }, S };
-
-translate({ '[]', Meta, Args } = Original, S) when is_list(Args) ->
-  case elixir_partials:handle(Original, S, allow_tail) of
-    error ->
-      [RTail|RArgs] = lists:reverse(Args),
-
-      case RTail of
-        {'|',_,[Left,Right]} ->
-          RExprs = [Left|RArgs],
-          TailFun = fun(ST) -> translate_each(Right, ST) end;
-        _ ->
-          RExprs = [RTail|RArgs],
-          TailFun = fun(ST) -> { { nil, ?line(Meta) }, ST } end
-      end,
-
-      { Exprs, SE } = translate_args(lists:reverse(RExprs), S),
-      { Tail, ST }  = TailFun(SE),
-      { elixir_utils:list_to_cons(?line(Meta), Exprs, Tail), ST };
-    Else -> Else
-  end;
+translate({ '{}', Meta, Args }, S) when is_list(Args) ->
+  { TArgs, SE } = translate_args(Args, S),
+  { { tuple, ?line(Meta), TArgs }, SE };

 translate({ Left, Right }, S) ->
  translate({ '{}', [], [Left, Right]}, S);

-translate(Args, S) when is_list(Args) ->
-  translate({ '[]', [], Args }, S);
+translate([], S) ->
+  { { nil, 0 }, S };
+
+translate([_|_] = Args, S) ->
+  [RTail|RArgs] = lists:reverse(Args),
+
+  case RTail of
+    { '|', _, [Left,Right] } ->
+      RExprs = [Left|RArgs],
+      TailFun = fun(ST) -> translate_each(Right, ST) end;
+    _ ->
+      RExprs = [RTail|RArgs],
+      TailFun = fun(ST) -> { { nil, 0 }, ST } end
+  end,
+
+  { Exprs, SE } = translate_args(lists:reverse(RExprs), S),
+  { Tail, ST }  = TailFun(SE),
+  { elixir_utils:list_to_cons(0, Exprs, Tail), ST };

 translate(Tuple, S) when is_tuple(Tuple) ->
  elixir_errors:compile_error(0, S#elixir_scope.file,
@@ -2,7 +2,7 @@
 %% but do not since they need to be implemented in Erlang.
 -module(elixir_macros).
 -export([translate/2]).
-import(elixir_translator, [translate_each/2, translate_args/2, translate_apply/7]).
+-import(elixir_translator, [translate_each/2]).
 -import(elixir_scope, [umergec/2, umergea/2]).
 -import(elixir_errors, [compile_error/3, syntax_error/3, syntax_error/4,
  assert_no_function_scope/3, assert_module_scope/3, assert_no_match_or_guard_scope/3]).
@@ -40,12 +40,7 @@ translate({ '!', Meta, [Expr] }, S) ->
  elixir_utils:convert_to_boolean(?line(Meta), TExpr, false, S#elixir_scope.context == guard, SE);

 translate({ in, Meta, [Left, Right] }, #elixir_scope{extra_guards=nil} = S) ->
-  { _, TExpr, TS } = translate_in(Meta, Left, Right, S),
-  { TExpr, TS };
-
-translate({ in, Meta, [Left, Right] }, #elixir_scope{extra_guards=Extra} = S) ->
-  { TVar, TExpr, TS } = translate_in(Meta, Left, Right, S),
-  { TVar, TS#elixir_scope{extra_guards=[TExpr|Extra]} };
+  translate_in(Meta, Left, Right, S);

 %% @

@@ -162,7 +157,7 @@ translate({defmodule, Meta, [Ref, KV]}, S) when is_list(KV) ->
      FullModule = expand_module(Ref, Module, S),

      RS = case elixir_aliases:nesting_alias(S#elixir_scope.module, FullModule) of
-        { New, Old } -> elixir_aliases:store(Meta, New, Old, S);
+        { New, Old } -> elixir_aliases:store(Meta, New, Old, [{warn,false}], S);
        false -> S
      end,

@@ -189,27 +184,6 @@ translate({Kind, Meta, [Call, Expr]}, S) when ?defs(Kind) ->
                   (not QC#elixir_quote.unquoted) andalso (not QE#elixir_quote.unquoted),
  { elixir_def:wrap_definition(Kind, Meta, TCall, TExpr, CheckClauses, SE), SE };

-translate({Kind, Meta, [Name, Args, Guards, Expr]}, S) when ?defs(Kind) ->
-  elixir_errors:deprecation(Meta, S#elixir_scope.file, "~ts/4 is deprecated, please use ~ts/2 instead", [Kind, Kind]),
-  assert_module_scope(Meta, Kind, S),
-  assert_no_function_scope(Meta, Kind, S),
-  { TName, SN }   = translate_each(Name, S),
-  { TArgs, SA }   = translate_each(Args, SN),
-  { TGuards, SG } = translate_each(Guards, SA),
-  { TExpr, SE }   = translate_each(Expr, SG),
-  { elixir_def:wrap_definition(Kind, Meta, TName, TArgs, TGuards, TExpr, false, SE), SE };
-
-%% Apply - Optimize apply by checking what doesn't need to be dispatched dynamically
-
-translate({ apply, Meta, [Left, Right, Args] }, S) when is_list(Args) ->
-  { TLeft,  SL } = translate_each(Left, S),
-  { TRight, SR } = translate_each(Right, umergec(S, SL)),
-  translate_apply(Meta, TLeft, TRight, Args, S, SL, SR);
-
-translate({ apply, Meta, Args }, S) ->
-  { TArgs, NS } = translate_args(Args, S),
-  { ?wrap_call(?line(Meta), erlang, apply, TArgs), NS };
-
 translate({ Name, Meta, Args }, S) ->
  syntax_error(Meta, S#elixir_scope.file,
               "invalid arguments for macro ~ts/~B", [Name, length(Args)]).
@@ -219,13 +193,7 @@ translate({ Name, Meta, Args }, S) ->
 translate_in(Meta, Left, Right, S) ->
  Line = ?line(Meta),

-  { TLeft, SL } = case Left of
-    { '_', _, Atom } when is_atom(Atom) ->
-      elixir_scope:build_erl_var(Line, S);
-    _ ->
-      translate_each(Left, S)
-  end,
-
+  { TLeft, SL }  = translate_each(Left, S),
  { TRight, SR } = translate_each(Right, SL),

  Cache = (S#elixir_scope.context == nil),
@@ -242,13 +210,13 @@ translate_in(Meta, Left, Right, S) ->
    { cons, _, _, _ } ->
      [H|T] = elixir_utils:cons_to_list(TRight),
      Expr = lists:foldr(fun(X, Acc) ->
-        { op, Line, 'orelse', { op, Line, '==', Var, X }, Acc }
-      end, { op, Line, '==', Var, H }, T),
+        { op, Line, 'orelse', { op, Line, '=:=', Var, X }, Acc }
+      end, { op, Line, '=:=', Var, H }, T),
      { Cache, Expr };
    { string, _, [H|T] } ->
      Expr = lists:foldl(fun(X, Acc) ->
-        { op, Line, 'orelse', { op, Line, '==', Var, { integer, Line, X } }, Acc }
-      end, { op, Line, '==', Var, { integer, Line, H } }, T),
+        { op, Line, 'orelse', { op, Line, '=:=', Var, { integer, Line, X } }, Acc }
+      end, { op, Line, '=:=', Var, { integer, Line, H } }, T),
      { Cache, Expr };
    { tuple, _, [{ atom, _, 'Elixir.Range' }, Start, End] } ->
      Expr = case { Start, End } of
@@ -277,8 +245,8 @@ translate_in(Meta, Left, Right, S) ->
  end,

  case TCache of
-    true  -> { Var, { block, Line, [ { match, Line, Var, TLeft }, TExpr ] }, SV };
-    false -> { Var, TExpr, SV }
+    true  -> { { block, Line, [ { match, Line, Var, TLeft }, TExpr ] }, SV };
+    false -> { TExpr, SV }
  end.

 increasing_compare(Line, Var, Start, End) ->
@@ -291,8 +259,18 @@ decreasing_compare(Line, Var, Start, End) ->
    { op, Line, '=<', Var, Start },
    { op, Line, '>=', Var, End } }.

-rewrite_case_clauses([{do,Meta1,[{in,_,[{'_',_,_},[false,nil]]}],False},{do,Meta2,[{'_',_,_}],True}]) ->
-  [{do,Meta1,[false],False},{do,Meta2,[true],True}];
+%% TODO: Once we have elixir_exp, we can move this
+%% clause to Elixir code and out of case.
+rewrite_case_clauses([
+    {do,Meta1,[{'when',_,[{V,M,C},{in,_,[{V,M,C},[false,nil]]}]}],False},
+    {do,Meta2,[{'_',_,UC}],True}] = Clauses)
+    when is_atom(V), is_list(M), is_atom(C), is_atom(UC) ->
+  case lists:keyfind('cond', 1, M) of
+    { 'cond', true } ->
+      [{do,Meta1,[false],False},{do,Meta2,[true],True}];
+    _ ->
+      Clauses
+  end;

 rewrite_case_clauses(Clauses) ->
  Clauses.
@@ -307,7 +285,8 @@ expand_module({ '__aliases__', _, [H] }, _Module, S) ->

 %% defmodule Hello.World
 expand_module({ '__aliases__', _, _ } = Alias, Module, S) ->
-  case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases) of
+  case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases,
+                             S#elixir_scope.lexical_tracker) of
    Atom when is_atom(Atom) ->
      Module;
    Aliases when is_list(Aliases) ->
@@ -319,6 +298,7 @@ expand_module(_Raw, Module, S) ->
  elixir_aliases:concat([S#elixir_scope.module, Module]).

 is_reserved_data(moduledoc) -> true;
+is_reserved_data(typedoc)   -> true;
 is_reserved_data(doc)       -> true;
 is_reserved_data(_)         -> false.

@@ -3,12 +3,14 @@
         eval_quoted/4, format_error/1, eval_callbacks/5]).
 -include("elixir.hrl").

-define(docs_attr, '__docs_table').
 -define(acc_attr, '__acc_attributes').
+-define(docs_attr, '__docs_table').
+-define(lexical_attr, '__lexical_tracker').
 -define(persisted_attr, '__persisted_attributes').
+-define(overridable_attr, '__overridable').

 eval_quoted(Module, Quoted, RawBinding, Opts) ->
-  Binding = elixir_scope:binding_for_eval(RawBinding, Module),
+  Binding = orddict:store('_@MODULE', Module, RawBinding),
  Scope   = scope_for_eval(Module, Opts),

  elixir_def:reset_last(Module),
@@ -23,7 +25,6 @@ eval_quoted(Module, Quoted, RawBinding, Opts) ->

 scope_for_eval(Module, #elixir_scope{} = S) ->
  S#elixir_scope{module=Module};
-
 scope_for_eval(Module, Opts) ->
  scope_for_eval(Module, elixir:scope_for_eval(Opts)).

@@ -42,9 +43,14 @@ docs_table(Module) ->
 %% will be passed to the invoked function.

 translate(Meta, Ref, Block, S) ->
-  Line            = ?line(Meta),
-  MetaBlock       = elixir_utils:elixir_to_erl(Line, Block, S),
-  { MetaS, Vars } = elixir_scope:serialize_with_vars(Line, S),
+  Line = ?line(Meta),
+  LexS = case S#elixir_scope.function of
+    nil -> S;
+    _ -> S#elixir_scope{lexical_tracker=nil}
+  end,
+
+  MetaBlock       = elixir_utils:elixir_to_erl(Line, Block, LexS),
+  { MetaS, Vars } = elixir_scope:serialize_with_vars(Line, LexS),

  Args = [{integer, Line, Line}, Ref, MetaBlock, Vars, MetaS],
  ?wrap_call(Line, ?MODULE, compile, Args).
@@ -62,15 +68,16 @@ compile(Line, Module, Block, Vars, #elixir_scope{context_modules=FileModules} =
  FileList = elixir_utils:characters_to_list(File),

  check_module_availability(Line, File, Module, C),
-  build(Line, File, Module),
+  build(Line, File, Module, S#elixir_scope.lexical_tracker),

  try
    Result = eval_form(Line, Module, Block, Vars, S),
    { Base, Export, Private, Def, Defmacro, Functions } = elixir_def:unwrap_stored_definitions(FileList, Module),

    { All, Forms0 } = functions_form(Line, File, Module, Base, Export, Def, Defmacro, Functions, C),
-    Forms1          = specs_form(Line, Module, Private, Defmacro, Forms0, C),
+    Forms1          = specs_form(Module, Private, Defmacro, Forms0, C),
    Forms2          = attributes_form(Line, File, Module, Forms1),
+    Forms3          = typedocs_form(Module, Forms2),

    case ets:lookup(data_table(Module), 'on_load') of
      [] -> ok;
@@ -80,16 +87,16 @@ compile(Line, Module, Block, Vars, #elixir_scope{context_modules=FileModules} =

    AllFunctions = Def ++ [T || { T, defp, _, _, _ } <- Private],
    elixir_tracker:ensure_no_function_conflict(Line, File, Module, AllFunctions),
-    elixir_tracker:ensure_all_imports_used(Line, File, Module),
    elixir_tracker:warn_unused_local(File, Module, Private),
-    warn_unused_docs(Line, File, Module, All),
+    warn_invalid_clauses(Line, File, Module, All),
+    warn_unused_docs(Line, File, Module),

    Final = [
      { attribute, Line, file, { FileList, Line } },
-      { attribute, Line, module, Module } | Forms2
+      { attribute, Line, module, Module } | Forms3
    ],

-    Binary = load_form(Line, Final, S),
+    Binary = load_form(Line, Final, compile_opts(Module), S),
    { module, Module, Binary, Result }
  after
    elixir_tracker:cleanup(Module),
@@ -108,7 +115,7 @@ compile(Line, Module, Block, Vars, RawS) ->

 %% Hook that builds both attribute and functions and set up common hooks.

-build(Line, File, Module) ->
+build(Line, File, Module, Lexical) ->
  %% Table with meta information about the module.
  DataTable = data_table(Module),

@@ -118,7 +125,6 @@ build(Line, File, Module) ->
  end,

  ets:new(DataTable, [set, named_table, public]),
-  ets:insert(DataTable, { '__overridable', [] }),
  ets:insert(DataTable, { before_compile, [] }),
  ets:insert(DataTable, { after_compile, [] }),

@@ -128,9 +134,11 @@ build(Line, File, Module) ->
  end,

  Attributes = [behavior, behaviour, on_load, spec, type, export_type, opaque, callback, compile],
-  ets:insert(DataTable, { ?acc_attr, [before_compile,after_compile,on_definition|Attributes] }),
+  ets:insert(DataTable, { ?acc_attr, [before_compile, after_compile, on_definition|Attributes] }),
  ets:insert(DataTable, { ?persisted_attr, [vsn|Attributes] }),
  ets:insert(DataTable, { ?docs_attr, ets:new(DataTable, [ordered_set, public]) }),
+  ets:insert(DataTable, { ?lexical_attr, Lexical }),
+  ets:insert(DataTable, { ?overridable_attr, [] }),

  %% Setup other modules
  elixir_def:setup(Module),
@@ -198,9 +206,21 @@ attributes_form(Line, _File, Module, Current) ->

  ets:foldl(Transform, Current, Table).

+%% Add typedocs to the form
+typedocs_form(Module, Current) ->
+  Table = docs_table(Module),
+  Transform = fun({ Tuple, Line, Kind, _Sig, Doc }, Acc) ->
+    case Kind of
+      type      -> [{ attribute, Line, typedoc, { Tuple, Doc } } | Acc];
+      opaque    -> [{ attribute, Line, typedoc, { Tuple, Doc } } | Acc];
+      _         -> Acc
+    end
+  end,
+  ets:foldl(Transform, Current, Table).
+
 %% Specs

-specs_form(Line, Module, Private, Defmacro, Forms, C) ->
+specs_form(Module, Private, Defmacro, Forms, C) ->
  Defmacrop = [Tuple || { Tuple, defmacrop, _, _, _ } <- Private],
  case elixir_compiler:get_opt(internal, C) of
    true -> Forms;
@@ -212,16 +232,17 @@ specs_form(Line, Module, Private, Defmacro, Forms, C) ->
      'Elixir.Module':delete_attribute(Module, spec),
      'Elixir.Module':delete_attribute(Module, callback),

-      Temp = specs_attributes(Line, spec, Forms, Specs),
-      specs_attributes(Line, callback, Temp, Callbacks)
+      Temp = specs_attributes(spec, Forms, Specs),
+      specs_attributes(callback, Temp, Callbacks)
  end.

-specs_attributes(Line, Type, Forms, Specs) ->
+specs_attributes(Type, Forms, Specs) ->
  Keys = lists:foldl(fun({ Tuple, Value }, Acc) ->
-                       lists:keystore(Tuple, 1, Acc, { Tuple, Value } )
+                       lists:keystore(Tuple, 1, Acc, { Tuple, Value })
                     end, [], Specs),
  lists:foldl(fun({ Tuple, _ }, Acc) ->
    Values = [V || { K, V } <- Specs, K == Tuple],
+    { type, Line, _, _ } = hd(Values),
    [{ attribute, Line, Type, { Tuple, Values } }|Acc]
  end, Forms, Keys).

@@ -246,8 +267,14 @@ spec_for_macro(Else) -> Else.

 %% Loads the form into the code server.

-load_form(Line, Forms, #elixir_scope{file=File} = S) ->
-  elixir_compiler:module(Forms, File, fun(Module, Binary) ->
+compile_opts(Module) ->
+  case ets:lookup(data_table(Module), compile) of
+    [{compile,Opts}] when is_list(Opts) -> Opts;
+    [] -> []
+  end.
+
+load_form(Line, Forms, Opts, #elixir_scope{file=File} = S) ->
+  elixir_compiler:module(Forms, File, Opts, fun(Module, Binary) ->
    EvalS = scope_for_eval(Module, S),
    Env = elixir_scope:to_ex_env({ Line, EvalS }),
    eval_callbacks(Line, Module, after_compile, [Env, Binary], EvalS),
@@ -259,8 +286,9 @@ load_form(Line, Forms, #elixir_scope{file=File} = S) ->
        case get(elixir_compiler_pid) of
          undefined -> [];
          PID ->
-            PID ! { module_available, self(), File, Module, Binary },
-            receive { PID, ack } -> ok end
+            Ref = make_ref(),
+            PID ! { module_available, self(), Ref, File, Module, Binary },
+            receive { Ref, ack } -> ok end
        end;
      _ ->
        []
@@ -282,18 +310,31 @@ check_module_availability(Line, File, Module, Compiler) ->
      []
  end.

-warn_unused_docs(_Line, _File, 'Elixir.Kernel', _All) -> ok;
-warn_unused_docs(_Line, _File, 'Elixir.Kernel.SpecialForms', _All) -> ok;
-warn_unused_docs(_Line, File, Module, All) ->
+warn_invalid_clauses(_Line, _File, 'Elixir.Kernel', _All) -> ok;
+warn_invalid_clauses(_Line, _File, 'Elixir.Kernel.SpecialForms', _All) -> ok;
+warn_invalid_clauses(_Line, File, Module, All) ->
  ets:foldl(fun
-    ({ Tuple, Line, _, _, _ }, Acc) ->
+    ({ _, _, Kind, _, _ }, _) when Kind == type; Kind == opaque ->
+      ok;
+    ({ Tuple, Line, _, _, _ }, _) ->
      case lists:member(Tuple, All) of
-        true  -> Acc;
        false ->
-          elixir_errors:handle_file_warning(File, { Line, ?MODULE, { invalid_doc, Tuple } })
+          elixir_errors:handle_file_warning(File, { Line, ?MODULE, { invalid_clause, Tuple } });
+        true ->
+          ok
      end
  end, ok, docs_table(Module)).

+warn_unused_docs(Line, File, Module) ->
+  lists:foreach(fun(Attribute) ->
+    case ets:member(data_table(Module), Attribute) of
+      true ->
+        elixir_errors:handle_file_warning(File, { Line, ?MODULE, { unused_doc, Attribute } });
+      _ ->
+        ok
+    end
+  end, [typedoc]).
+
 % EXTRA FUNCTIONS

 add_info_function(Line, File, Module, Export, Def, Defmacro, C) ->
@@ -329,7 +370,10 @@ module_clause(Module) ->
  { clause, 0, [{ atom, 0, module }], [], [{ atom, 0, Module }] }.

 docs_clause(Module, true) ->
-  Docs = ordsets:from_list(ets:tab2list(docs_table(Module))),
+  Docs = ordsets:from_list(
+    [{Tuple, Line, Kind, Sig, Doc} ||
+     {Tuple, Line, Kind, Sig, Doc} <- ets:tab2list(docs_table(Module)),
+     Kind =/= type, Kind =/= opaque]),
  { clause, 0, [{ atom, 0, docs }], [], [elixir_utils:elixir_to_erl(Docs)] };

 docs_clause(_Module, _) ->
@@ -349,8 +393,7 @@ else_clause() ->
 % HELPERS

 eval_callbacks(Line, Module, Name, Args, RawS) ->
-  Binding   = elixir_scope:binding_for_eval([], Module),
-  S         = elixir_scope:vars_from_binding(RawS, Binding),
+  { Binding, S } = elixir_scope:load_binding([], RawS, Module),
  Callbacks = lists:reverse(ets:lookup_element(data_table(Module), Name, 2)),
  Meta      = [{line,Line},{require,false}],

@@ -369,25 +412,34 @@ eval_callbacks(Line, Module, Name, Args, RawS) ->
        catch
          Kind:Reason ->
            Info = { M, F, length(Args), [{ file, elixir_utils:characters_to_list(S#elixir_scope.file) }, { line, Line }] },
-            erlang:raise(Kind, Reason, munge_stacktrace(Info, erlang:get_stacktrace()))
+            erlang:raise(Kind, Reason, prune_stacktrace(Info, erlang:get_stacktrace()))
        end
    end
  end, Callbacks).

-%% We've reached the elixir_dispatch internals, skip it with the rest
-munge_stacktrace(Info, [{ elixir_module, _, _, _ }|_]) ->
+%% We've reached the elixir_module or erl_eval internals, skip it with the rest
+prune_stacktrace(Info, [{ erl_eval, _, _, _ }|_]) ->
  [Info];

-munge_stacktrace(Info, [H|T]) ->
-  [H|munge_stacktrace(Info, T)];
+prune_stacktrace(Info, [{ elixir_module, _, _, _ }|_]) ->
+  [Info];

-munge_stacktrace(Info, []) ->
+prune_stacktrace(Info, [H|T]) ->
+  [H|prune_stacktrace(Info, T)];
+
+prune_stacktrace(Info, []) ->
  [Info].

 % ERROR HANDLING

-format_error({ invalid_doc, { Name, Arity } }) ->
-  io_lib:format("docs provided for nonexistent function or macro ~ts/~B", [Name, Arity]);
+format_error({ invalid_clause, { Name, Arity } }) ->
+  io_lib:format("empty clause provided for nonexistent function or macro ~ts/~B", [Name, Arity]);
+
+format_error({ unused_doc, typedoc }) ->
+  "@typedoc provided but no type follows it";
+
+format_error({ unused_doc, doc }) ->
+  "@doc provided but no definition follows it";

 format_error({ internal_function_overridden, { Name, Arity } }) ->
  io_lib:format("function ~ts/~B is internal and should not be overridden", [Name, Arity]);
@@ -20,7 +20,7 @@ Nonterminals
  call_args_no_parens_kw_expr call_args_no_parens_kw_comma call_args_no_parens_kw
  dot_op dot_alias dot_identifier dot_op_identifier dot_do_identifier
  dot_paren_identifier dot_bracket_identifier
-  var list bracket_access bit_string tuple
+  var list bit_string tuple
  do_block fn_eol do_eol end_eol block_eol block_item block_list
  .

@@ -28,7 +28,7 @@ Terminals
  identifier kw_identifier bracket_identifier
  paren_identifier do_identifier block_identifier
  fn 'end' aliases
-  number signed_number atom bin_string list_string sigil
+  number signed_number atom atom_string bin_string list_string sigil
  dot_call_op op_identifier
  comp_op at_op unary_op and_op or_op arrow_op match_op
  range_op in_op inc_op when_op than_op default_op tail_op
@@ -179,20 +179,20 @@ max_expr -> parens_call call_args_parens call_args_parens : build_nested_parens(
 max_expr -> dot_alias : '$1'.
 max_expr -> base_expr : '$1'.

-bracket_expr -> dot_bracket_identifier bracket_access : build_access(build_identifier('$1', nil), '$2').
-bracket_expr -> max_expr bracket_access : build_access('$1', '$2').
+bracket_expr -> dot_bracket_identifier list : build_access(build_identifier('$1', nil), '$2').
+bracket_expr -> max_expr list : build_access('$1', '$2').

-bracket_at_expr -> at_op_eol dot_bracket_identifier bracket_access :
+bracket_at_expr -> at_op_eol dot_bracket_identifier list :
                     build_access(build_unary_op('$1', build_identifier('$2', nil)), '$3').
-bracket_at_expr -> at_op_eol max_expr bracket_access :
+bracket_at_expr -> at_op_eol max_expr list :
                     build_access(build_unary_op('$1', '$2'), '$3').
-bracket_at_expr -> bracket_at_expr bracket_access :
+bracket_at_expr -> bracket_at_expr list :
                     build_access('$1', '$2').

+base_expr -> atom : ?exprs('$1').
 base_expr -> number : ?exprs('$1').
 base_expr -> signed_number : { element(4, '$1'), [{line,?line('$1')}], ?exprs('$1') }.
-base_expr -> atom : build_atom('$1').
-base_expr -> list : '$1'.
+base_expr -> list : element(1, '$1').
 base_expr -> tuple : '$1'.
 base_expr -> 'true' : ?id('$1').
 base_expr -> 'false' : ?id('$1').
@@ -200,6 +200,7 @@ base_expr -> 'nil' : ?id('$1').
 base_expr -> aliases : { '__aliases__', [{line,?line('$1')}], ?exprs('$1') }.
 base_expr -> bin_string  : build_bin_string('$1').
 base_expr -> list_string : build_list_string('$1').
+base_expr -> atom_string : build_atom_string('$1').
 base_expr -> bit_string : '$1'.
 base_expr -> sigil : build_sigil('$1').
 base_expr -> '&' number : { '&', [{line,?line('$1')}], [?exprs('$2')] }.
@@ -434,21 +435,17 @@ kw -> kw_expr : ['$1'].
 kw -> kw_comma : lists:reverse('$1').
 kw -> kw_comma kw_expr : lists:reverse(['$2'|'$1']).

-call_args_no_parens_kw_expr -> kw_eol call_args_no_parens_expr : {?exprs('$1'),'$2'}.
+call_args_no_parens_kw_expr -> kw_eol call_args_no_parens_expr : { ?exprs('$1'),'$2' }.
 call_args_no_parens_kw_comma -> call_args_no_parens_kw_expr : ['$1'].
 call_args_no_parens_kw_comma -> call_args_no_parens_kw_expr ',' call_args_no_parens_kw_comma : ['$1'|'$3'].
 call_args_no_parens_kw -> call_args_no_parens_kw_comma : '$1'.

 % Lists

-bracket_access -> open_bracket ']' : { [], ?line('$1') }.
-bracket_access -> open_bracket container_arg close_bracket : { '$2', ?line('$1') }.
-bracket_access -> open_bracket kw close_bracket : { '$2', ?line('$1') }.
-
-list -> open_bracket ']' : [].
-list -> open_bracket kw close_bracket : '$2'.
-list -> open_bracket container_arg close_bracket : ['$2'].
-list -> open_bracket container_expr ',' container_args close_bracket : ['$2'|'$4'].
+list -> open_bracket ']' : { [], ?line('$1') }.
+list -> open_bracket kw close_bracket : { '$2', ?line('$1') }.
+list -> open_bracket container_arg close_bracket : { ['$2'], ?line('$1') }.
+list -> open_bracket container_expr ',' container_args close_bracket : { ['$2'|'$4'], ?line('$1') }.

 % Tuple

@@ -548,32 +545,56 @@ extract_identifier(Other) -> Other.
 %% Fn

 build_fn(Op, Stab) ->
-  { fn, [{line,?line(Op)}], [[{ do, Stab }]] }.
+  { fn, [{line,?line(Op)}], [Stab] }.

 %% Access

-build_access(Expr, Access) ->
-  Meta = [{line,?line(Access)}],
-  { { '.', Meta, ['Elixir.Kernel', access] }, Meta, [ Expr, ?id(Access) ] }.
+build_access(Expr, { List, Line }) ->
+  Meta = [{line,Line}],
+  { { '.', Meta, ['Elixir.Kernel', access] }, Meta, [Expr, List] }.

 %% Interpolation aware

 build_sigil({ sigil, Line, Sigil, Parts, Modifiers }) ->
  Meta = [{line,Line}],
-  { list_to_atom("sigil_" ++ [Sigil]), Meta, [ { '<<>>', Meta, Parts }, Modifiers ] }.
+  { list_to_atom("sigil_" ++ [Sigil]), Meta, [ { '<<>>', Meta, string_parts(Parts) }, Modifiers ] }.

-build_bin_string({ bin_string, _Line, [H] }) when is_binary(H) -> H;
-build_bin_string({ bin_string, Line, Args }) -> { '<<>>', [{line,Line}], Args }.
+build_bin_string({ bin_string, _Line, [H] }) when is_binary(H) ->
+  H;
+build_bin_string({ bin_string, Line, Args }) ->
+  { '<<>>', [{line,Line}], string_parts(Args) }.

-build_list_string({ list_string, _Line, [H] }) when is_binary(H) -> elixir_utils:characters_to_list(H);
+build_list_string({ list_string, _Line, [H] }) when is_binary(H) ->
+  elixir_utils:characters_to_list(H);
 build_list_string({ list_string, Line, Args }) ->
  Meta = [{line,Line}],
-  { { '.', Meta, ['Elixir.String', 'to_char_list!'] }, Meta, [{ '<<>>', Meta, Args}] }.
+  { { '.', Meta, ['Elixir.String', 'to_char_list!'] }, Meta, [{ '<<>>', Meta, string_parts(Args) }] }.

-build_atom({ atom, _Line, Atom }) when is_atom(Atom) -> Atom;
-build_atom({ atom, Line, Args }) ->
+build_atom_string({ atom_string, _Line, Safe, [H] }) when is_binary(H) ->
+  Op = binary_to_atom_op(Safe), erlang:Op(H, utf8);
+build_atom_string({ atom_string, Line, Safe, Args }) ->
  Meta = [{line,Line}],
-  { { '.', Meta, [erlang, binary_to_atom] }, Meta, [{ '<<>>', Meta, Args }, utf8] }.
+  { { '.', Meta, [erlang, binary_to_atom_op(Safe)] }, Meta, [{ '<<>>', Meta, string_parts(Args) }, utf8] }.
+
+binary_to_atom_op(true)  -> binary_to_existing_atom;
+binary_to_atom_op(false) -> binary_to_atom.
+
+string_parts(Parts) ->
+  [string_part(Part) || Part <- Parts].
+string_part(Binary) when is_binary(Binary) ->
+  Binary;
+string_part({ Line, Tokens }) ->
+  Form = string_tokens_parse(Line, Tokens),
+  Meta = [{line,Line}],
+  { '::', Meta, [{ { '.', Meta, ['Elixir.Kernel', to_string] }, Meta, [Form]}, { binary, Meta, nil }]}.
+
+string_tokens_parse(Line, Tokens) ->
+  case parse(Tokens) of
+    { ok, [] } -> nil;
+    { ok, [Forms] } when not is_list(Forms) -> Forms;
+    { ok, Forms } -> { '__block__', [{line, Line}], Forms };
+    { error, _ } = Error -> throw(Error)
+  end.

 %% Keywords

@@ -1,65 +0,0 @@
-%% Responsible handling Elixir partials with &1, &2 and so on.
-module(elixir_partials).
-export([handle/2, handle/3, is_sequential/1]).
-include("elixir.hrl").
-
-handle(Original, S) ->
-  handle(Original, S, default).
-
-handle({ _, Meta, Args } = Original, S, Opt) when is_list(Args), S#elixir_scope.context /= match ->
-  case convert(Args, S, Opt) of
-    { Call, Def, SC } when Def /= [] ->
-      Final = validate(Meta, Def, SC),
-      Block = setelement(3, Original, Call),
-      elixir_fn:fn(Meta, [{ Final, Meta, Block }], SC);
-    _ -> error
-  end;
-
-handle(_Original, _S, _Opt) ->
-  error.
-
-validate(Meta, Def, S) ->
-  validate(Meta, lists:sort(Def), 1, S).
-
-validate(Meta, [{ Pos, Item }|T], Pos, S) ->
-  [Item|validate(Meta, T, Pos + 1, S)];
-
-validate(Meta, [{ Pos, _ }|_], Expected, S) ->
-  elixir_errors:syntax_error(Meta, S#elixir_scope.file, "partial variable &~w cannot be defined without &~w", [Pos, Expected]);
-
-validate(_Meta, [], _Pos, _S) ->
-  [].
-
-%% This function receives arguments and then checks
-%% the args for partial application. It returns a tuple
-%% with three elements where the first element is the list
-%% of call args, the second the list of def args for the
-%% function definition and the third one is the new scope.
-convert(List, S, Opt) -> convert(List, S, Opt, [], []).
-
-convert([{'|', Meta, [_, _] = Args}|T], S, allow_tail, CallAcc, DefAcc) ->
-  { NewArgs, NewDef, NewS } = convert(Args, S, allow_tail, [], DefAcc),
-  convert(T, NewS, allow_tail, [{ '|', Meta, NewArgs}|CallAcc], NewDef);
-
-convert([{'&', Meta, [Pos]}|T], S, Opt, CallAcc, DefAcc) when is_integer(Pos) ->
-  case lists:keyfind(Pos, 1, DefAcc) of
-    false ->
-      { Var, SC } = elixir_scope:build_ex_var(?line(Meta), S),
-      convert(T, SC, Opt, [Var|CallAcc], [{Pos,Var}|DefAcc]);
-    {Pos,Var} ->
-      convert(T, S, Opt, [Var|CallAcc], DefAcc)
-  end;
-
-convert([H|T], S, Opt, CallAcc, DefAcc) ->
-  convert(T, S, Opt, [H|CallAcc], DefAcc);
-
-convert([], S, _Opt, CallAcc, DefAcc) ->
-  { lists:reverse(CallAcc), lists:reverse(DefAcc), S }.
-
-is_sequential(List) -> is_sequential(List, 1).
-
-is_sequential([{ '&', _, [Int] }|T], Int) ->
-  is_sequential(T, Int + 1);
-
-is_sequential([], Int) when Int > 1 -> true;
-is_sequential(_, _Int) -> false.
@@ -1,33 +1,47 @@
 %% Implements Elixir quote.
 -module(elixir_quote).
-export([escape/2, erl_escape/3, erl_quote/4, linify/2, unquote/6, join/5]).
+-export([escape/2, erl_escape/3, erl_quote/4,
+         linify/2, linify/3, unquote/4, tail_join/3, join/2]).
 -include("elixir.hrl").

 %% Apply the line from site call on quoted contents.
 linify(Line, Exprs) when is_integer(Line) ->
-  do_linify(Line, Exprs).
+  do_linify(Line, nil, Exprs).

-do_linify(Line, { Left, Meta, Right }) ->
+linify(Line, Var, Exprs) when is_integer(Line) ->
+  do_linify(Line, Var, Exprs).
+
+do_linify(Line, { Receiver, Counter } = Var, { Left, Meta, Receiver }) when is_atom(Left), is_list(Meta) ->
+  NewMeta = case keyfind(counter, Meta) of
+    { counter, _ } -> Meta;
+    _ -> keystore(counter, Meta, Counter)
+  end,
+  do_tuple_linify(Line, Var, NewMeta, Left, Receiver);
+
+do_linify(Line, Var, { Left, Meta, Right }) when is_list(Meta) ->
+  do_tuple_linify(Line, Var, Meta, Left, Right);
+
+do_linify(Line, Var, { Left, Right }) ->
+  { do_linify(Line, Var, Left), do_linify(Line, Var, Right) };
+
+do_linify(Line, Var, List) when is_list(List) ->
+  [do_linify(Line, Var, X) || X <- List];
+
+do_linify(_, _, Else) -> Else.
+
+do_tuple_linify(Line, Var, Meta, Left, Right) ->
  NewMeta = case ?line(Meta) of
    0 -> keystore(line, Meta, Line);
    _ -> Meta
  end,
-  { do_linify(Line, Left), NewMeta, do_linify(Line, Right) };
-
-do_linify(Line, { Left, Right }) ->
-  { do_linify(Line, Left), do_linify(Line, Right) };
-
-do_linify(Line, List) when is_list(List) ->
-  [do_linify(Line, X) || X <- List];
-
-do_linify(_, Else) -> Else.
+  { do_linify(Line, Var, Left), NewMeta, do_linify(Line, Var, Right) }.

 %% Some expressions cannot be unquoted at compilation time.
 %% This function is responsible for doing runtime unquoting.
-unquote(_File, _Line, Meta, Left, { '__aliases__', _, Args }, nil) ->
+unquote(Meta, Left, { '__aliases__', _, Args }, nil) ->
  { '__aliases__', Meta, [Left|Args] };

-unquote(_File, _Line, Meta, Left, Right, nil) when is_atom(Right) ->
+unquote(Meta, Left, Right, nil) when is_atom(Right) ->
  case atom_to_list(Right) of
    "Elixir." ++ _ ->
      { '__aliases__', Meta, [Left, Right] };
@@ -35,33 +49,48 @@ unquote(_File, _Line, Meta, Left, Right, nil) when is_atom(Right) ->
      { { '.', Meta, [Left, Right] }, Meta, [] }
  end;

-unquote(_File, _Line, Meta, Left, { Right, _, Context }, nil) when is_atom(Right), is_atom(Context) ->
+unquote(Meta, Left, { Right, _, Context }, nil) when is_atom(Right), is_atom(Context) ->
  { { '.', Meta, [Left, Right] }, Meta, [] };

-unquote(_File, _Line, Meta, Left, { Right, _, Args }, nil) when is_atom(Right) ->
+unquote(Meta, Left, { Right, _, Args }, nil) when is_atom(Right) ->
  { { '.', Meta, [Left, Right] }, Meta, Args };

-unquote(File, Line, _Meta, _Left, Right, nil) ->
-  elixir_errors:syntax_error(Line, File, "expected unquote after dot to return an atom, "
-    "an alias or a quoted call, got: ~ts", ['Elixir.Macro':to_string(Right)]);
+unquote(_Meta, _Left, Right, nil) ->
+  argument_error(<<"expected unquote after dot to return an atom, an alias or a quoted call, got: ",
+                   ('Elixir.Macro':to_string(Right))/binary>>);

-unquote(_File, _Line, Meta, Left, Right, Args) when is_atom(Right) ->
+unquote(Meta, Left, Right, Args) when is_atom(Right) ->
  { { '.', Meta, [Left, Right] }, Meta, Args };

-unquote(_File, _Line, Meta, Left, { Right, _, Context }, Args) when is_atom(Right), is_atom(Context) ->
+unquote(Meta, Left, { Right, _, Context }, Args) when is_atom(Right), is_atom(Context) ->
  { { '.', Meta, [Left, Right] }, Meta, Args };

-unquote(File, Line, _Meta, _Left, Right, _Args) ->
-  elixir_errors:syntax_error(Line, File, "expected unquote after dot with args to return an atom "
-    "or a quoted call, got: ~ts", ['Elixir.Macro':to_string(Right)]).
+unquote(_Meta, _Left, Right, _Args) ->
+  argument_error(<<"expected unquote after dot with args to return an atom or a quoted call, got: ",
+                   ('Elixir.Macro':to_string(Right))/binary>>).

-join(_File, _Line, Left, Right, Rest) when is_list(Left), is_list(Right), is_list(Rest) ->
-  Rest ++ Left ++ Right;
+join(Left, Right) when is_list(Right) ->
+  validate_join(Left),
+  Left ++ Right.

-join(_File, _Line, Left, Right, Rest)  ->
-  [H|T] = lists:reverse(Rest ++ Left),
+tail_join(Left, Right, Tail) when is_list(Right), is_list(Tail) ->
+  validate_join(Left),
+  Tail ++ Left ++ Right;
+
+tail_join(Left, Right, Tail) when is_list(Left) ->
+  validate_join(Left),
+  [H|T] = lists:reverse(Tail ++ Left),
  lists:reverse([{ '|', [], [H, Right] }|T]).

+validate_join(List) when is_list(List) ->
+  ok;
+validate_join(List) when not is_list(List) ->
+  argument_error(<<"expected a list with quoted expressions in unquote_splicing/1, got: ",
+                   ('Elixir.Kernel':inspect(List))/binary>>).
+
+argument_error(Message) ->
+  error('Elixir.ArgumentError':exception([{message,Message}])).
+
 %% Escapes the given expression. It is similar to quote, but
 %% lines are kept and hygiene mechanisms are disabled.
 escape(Expr, Unquote) ->
@@ -113,7 +142,24 @@ do_quote({ unquote, _Meta, [Expr] }, #elixir_quote{unquote=true} = Q, _) ->

 %% Context mark

-do_quote({ Def, Meta, Args }, #elixir_quote{escape=false} = Q, S) when ?defs(Def); Def == defmodule; Def == alias; Def == import ->
+do_quote({ defmodule, Meta, [_|_] = Args }, #elixir_quote{escape=false} = Q, S) ->
+  %% Only store the context if we actually have a full alias as
+  %% argument, otherwise the expression is being automatically
+  %% generated and we don't want the alias to count.
+  NewMeta =
+    case hd(Args) of
+      { '__aliases__', _, Atoms } ->
+        case lists:all(fun is_atom/1, Atoms) of
+          true  -> keystore(context, Meta, Q#elixir_quote.context);
+          false -> Meta
+        end;
+      _ ->
+        Meta
+    end,
+
+  do_quote_tuple({ defmodule, NewMeta, Args }, Q, S);
+
+do_quote({ Def, Meta, [_|_] = Args }, #elixir_quote{escape=false} = Q, S) when ?defs(Def); Def == alias; Def == import ->
  NewMeta = keystore(context, Meta, Q#elixir_quote.context),
  do_quote_tuple({ Def, NewMeta, Args }, Q, S);

@@ -128,7 +174,7 @@ do_quote({ 'alias!', _Meta, [Expr] }, #elixir_quote{aliases_hygiene=true} = Q, S
  { TExpr, TQ#elixir_quote{aliases_hygiene=true} };

 do_quote({ '__aliases__', Meta, [H|T] } = Alias, #elixir_quote{aliases_hygiene=true} = Q, S) when is_atom(H) and (H /= 'Elixir') ->
-  Annotation = case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases) of
+  Annotation = case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases, S#elixir_scope.lexical_tracker) of
    Atom when is_atom(Atom) -> Atom;
    Aliases when is_list(Aliases) -> false
  end,
@@ -214,9 +260,9 @@ do_quote(Other, Q, _) ->
 %% Quote helpers

 do_quote_call(Left, Meta, Expr, Args, Q, S) ->
-  All  = [?line(Meta), meta(Meta, Q), Left, { unquote, Meta, [Expr] }, Args],
+  All  = [meta(Meta, Q), Left, { unquote, Meta, [Expr] }, Args],
  { TAll, TQ } = lists:mapfoldl(fun(X, Acc) -> do_quote(X, Acc, S) end, Q, All),
-  { { { '.', Meta, [elixir_quote, unquote] }, Meta, [{ '__FILE__', [], nil }|TAll] }, TQ }.
+  { { { '.', Meta, [elixir_quote, unquote] }, Meta, TAll }, TQ }.

 do_quote_fa(Target, Meta, Args, F, A, Q, S) ->
  NewMeta =
@@ -264,24 +310,24 @@ do_splice([{ '|', Meta, [{ unquote_splicing, _, [Left] }, Right] }|T], #elixir_q
  %% 1, 2 and 3, which could even be unquotes.
  { TT, QT } = do_splice(T, Q, S, [], []),
  { TR, QR } = do_quote(Right, QT, S),
-
-  %% Do the joining at runtime when we are aware of the values.
-  Args = [{ '__FILE__', [], nil }, ?line(Meta), Left, TR, TT],
-  { { { '.', Meta, [elixir_quote, join] }, Meta, Args }, QR#elixir_quote{unquoted=true} };
+  { do_runtime_join(Meta, tail_join, [Left, TR, TT]), QR#elixir_quote{unquoted=true} };

 do_splice(List, Q, S) ->
  do_splice(List, Q, S, [], []).

-do_splice([{ unquote_splicing, _, [Expr] }|T], #elixir_quote{unquote=true} = Q, S, Buffer, Acc) ->
-  do_splice(T, Q#elixir_quote{unquoted=true}, S, [], do_splice_join(do_splice_join(Expr, Buffer), Acc));
+do_splice([{ unquote_splicing, Meta, [Expr] }|T], #elixir_quote{unquote=true} = Q, S, Buffer, Acc) ->
+  do_splice(T, Q#elixir_quote{unquoted=true}, S, [], do_runtime_join(Meta, join, [Expr, do_join(Buffer, Acc)]));

 do_splice([H|T], Q, S, Buffer, Acc) ->
  { TH, TQ } = do_quote(H, Q, S),
  do_splice(T, TQ, S, [TH|Buffer], Acc);

 do_splice([], Q, _S, Buffer, Acc) ->
-  { do_splice_join(Buffer, Acc), Q }.
+  { do_join(Buffer, Acc), Q }.

-do_splice_join(Left, [])    -> Left;
-do_splice_join([], Right)   -> Right;
-do_splice_join(Left, Right) -> { { '.', [], ['Elixir.Kernel', '++'] }, [], [Left, Right] }.
+do_join(Left, [])    -> Left;
+do_join([], Right)   -> Right;
+do_join(Left, Right) -> { { '.', [], ['Elixir.Kernel', '++'] }, [], [Left, Right] }.
+
+do_runtime_join(Meta, Fun, Args) ->
+  { { '.', Meta, [elixir_quote, Fun] }, Meta, Args }.
@@ -2,17 +2,20 @@
 -module(elixir_scope).
 -export([translate_var/5,
  build_erl_var/2, build_ex_var/2,
-  serialize/1, deserialize/1,
+  serialize/1, deserialize/1, to_erl/1,
  serialize_with_vars/2, deserialize_with_vars/2,
  to_erl_env/1, to_ex_env/1,
-  vars_from_binding/2, binding_for_eval/2, binding_from_vars/2,
+  load_binding/3, dump_binding/2,
  umergev/2, umergec/2, umergea/2, merge_clause_vars/2
 ]).
 -include("elixir.hrl").

-translate_var(Meta, Name, Kind, S, Callback) ->
+%% VAR HANDLING
+
+translate_var(Meta, Name, Kind, S, Callback) when is_atom(Kind); is_integer(Kind) ->
  Line = ?line(Meta),
  Vars = S#elixir_scope.vars,
+  Temp = lists:keyfind(temp, 1, Meta) == { temp, true },
  Tuple = { Name, Kind },

  case Name of
@@ -41,7 +44,7 @@ translate_var(Meta, Name, Kind, S, Callback) ->
                  true -> ordsets:add_element(Tuple, TempVars)
                end,
                clause_vars=if
-                  ClauseVars == nil; Kind == false -> ClauseVars;
+                  ClauseVars == nil; Temp == true -> ClauseVars;
                  true -> orddict:store(Tuple, RealName, ClauseVars)
                end
              } }
@@ -78,43 +81,54 @@ build_ex_var(Line, Key, Name, S) when is_integer(Line) ->
  Var = { ?atom_concat([Name, "@", Counter]), [{line,Line}], Context },
  { Var, NS }.

-% Handle Macro.Env conversion
+%% Macro.Env <-> #elixir_scope conversion

 to_erl_env({ 'Elixir.Macro.Env', Module, File, _Line, Function, Aliases, Context,
-    Requires, Functions, Macros, ContextModules, MacroAliases, Vars }) ->
+    Requires, Functions, Macros, ContextModules, MacroAliases, _Vars, Lexical }) ->
  #elixir_scope{module=Module,file=File,
    function=Function,aliases=Aliases,context=Context,
    requires=Requires,macros=Macros,functions=Functions,
    context_modules=ContextModules,macro_aliases=MacroAliases,
-    list_vars=Vars}.
+    lexical_tracker=Lexical}.

 to_ex_env({ Line, #elixir_scope{module=Module,file=File,
    function=Function,aliases=Aliases,context=Context,
    requires=Requires,macros=Macros,functions=Functions,
    context_modules=ContextModules,macro_aliases=MacroAliases,
-    vars=Vars,list_vars=ListVars} }) when is_integer(Line) ->
+    vars=Vars,lexical_tracker=Lexical} }) when is_integer(Line) ->
  { 'Elixir.Macro.Env', Module, File, Line, Function, Aliases,
    Context, Requires, Functions, Macros, ContextModules, MacroAliases,
-    list_vars(ListVars, Vars) }.
+    list_vars(Vars), Lexical }.

-list_vars(nil, Vars) -> [K || { K, _ } <- Vars];
-list_vars(Other, _)  -> Other.
+list_vars(Vars) -> [Pair || { { _, K } = Pair, _ } <- Vars, is_atom(K)].

-% Provides a tuple with only the scope information we want to serialize.
+%% SERIALIZATION
+
+%% When serializing scopes, we support serialization of pids.
+to_erl(Structure) ->
+  elixir_utils:elixir_to_erl(Structure, fun
+    (X) when is_pid(X) ->
+      ?wrap_call(0, erlang, binary_to_term, [elixir_utils:elixir_to_erl(term_to_binary(X))]);
+    (Other) ->
+      error({ badarg, Other })
+  end).

 serialize(S) ->
-  elixir_utils:elixir_to_erl(
-    { S#elixir_scope.file, S#elixir_scope.functions,
-      S#elixir_scope.requires, S#elixir_scope.macros, S#elixir_scope.aliases,
-      S#elixir_scope.macro_functions, S#elixir_scope.macro_macros, S#elixir_scope.macro_aliases,
-      S#elixir_scope.context_modules }
-  ).
+  to_erl({ S#elixir_scope.file, S#elixir_scope.functions,
+    S#elixir_scope.requires, S#elixir_scope.macros, S#elixir_scope.aliases,
+    S#elixir_scope.macro_functions, S#elixir_scope.macro_macros, S#elixir_scope.macro_aliases,
+    S#elixir_scope.context_modules, S#elixir_scope.lexical_tracker }).

 serialize_with_vars(Line, S) when is_integer(Line) ->
  { Vars, _ } = orddict:fold(fun({ Key, Kind }, Value, { Acc, Counter }) ->
+    KindKey = if
+      is_atom(Kind) -> atom;
+      is_integer(Kind) -> integer
+    end,
+
    { { cons, Line, { tuple, Line, [
      { atom, Line, Key },
-      { atom, Line, Kind },
+      { KindKey, Line, Kind },
      { atom, Line, ?atom_concat(["_@", Counter]) },
      { var,  Line, Value }
    ] }, Acc }, Counter + 1 }
@@ -125,8 +139,8 @@ serialize_with_vars(Line, S) when is_integer(Line) ->

 deserialize(Tuple) -> deserialize_with_vars(Tuple, []).

-deserialize_with_vars({ File, Functions, Requires, Macros,
-                        Aliases, MacroFunctions, MacroMacros, MacroAliases, FileModules }, Vars) ->
+deserialize_with_vars({ File, Functions, Requires, Macros, Aliases, MacroFunctions,
+                        MacroMacros, MacroAliases, FileModules, LexicalTracker }, Vars) ->
  #elixir_scope{
    file=File,
    functions=Functions,
@@ -138,9 +152,12 @@ deserialize_with_vars({ File, Functions, Requires, Macros,
    macro_aliases=MacroAliases,
    context_modules=FileModules,
    vars=orddict:from_list(Vars),
+    lexical_tracker=LexicalTracker,
    counter=[{'',length(Vars)}]
  }.

+%% SCOPE MERGING
+
 %% Receives two scopes and return a new scope based on the second
 %% with their variables merged.

@@ -160,6 +177,7 @@ umergev(S1, S2) ->
 umergec(S1, S2) ->
  S1#elixir_scope{
    counter=S2#elixir_scope.counter,
+    macro_counter=S2#elixir_scope.macro_counter,
    extra_guards=S2#elixir_scope.extra_guards,
    super=S2#elixir_scope.super,
    caller=S2#elixir_scope.caller
@@ -202,39 +220,42 @@ var_number([$@|T], _Acc) -> var_number(T, []);
 var_number([H|T], Acc)   -> var_number(T, [H|Acc]);
 var_number([], Acc)      -> list_to_integer(lists:reverse(Acc)).

-%% Setup the vars in scope from binding
+%% BINDINGS

-vars_from_binding(Scope, Binding) ->
-  Scope#elixir_scope{
-    vars=binding_dict(Binding),
+load_binding(Binding, Scope, Module) ->
+  { NewBinding, NewVars, NewCounter } = load_binding(Binding, [], [], 0, Module),
+  { NewBinding, Scope#elixir_scope{
+    vars=NewVars,
    temp_vars=[],
    clause_vars=nil,
-    counter=[]
-  }.
+    counter=[{'',NewCounter}]
+  } }.

-binding_dict(List) -> binding_dict(List, orddict:new()).
-binding_dict([{{H,Kind},_}|T], Dict) -> binding_dict(T, orddict:store({ H, Kind }, H, Dict));
-binding_dict([{H,_}|T], Dict) -> binding_dict(T, orddict:store({ H, nil }, H, Dict));
-binding_dict([], Dict) -> Dict.
+load_binding([{'_@MODULE',Value}|T], Binding, Vars, Counter, _Module) ->
+  load_binding(T, Binding, Vars, Counter, Value);
+load_binding([{Key,Value}|T], Binding, Vars, Counter, Module) ->
+  Actual = case Key of
+    { _Name, _Kind } -> Key;
+    Name when is_atom(Name) -> { Name, nil }
+  end,
+  InternalName = ?atom_concat(["_@", Counter]),
+  load_binding(T,
+    [{InternalName,Value}|Binding],
+    orddict:store(Actual, InternalName, Vars),
+    Counter + 1, Module);
+load_binding([], Binding, Vars, Counter, Module) ->
+  { lists:reverse([{'_@MODULE',Module}|Binding]), Vars, Counter }.

-binding_for_eval(Binding, Module) ->
-  Keyword = orddict:from_list(Binding),
-  case orddict:find('_@MODULE', Keyword) of
-    { ok, _ } -> Keyword;
-    _ -> orddict:store('_@MODULE', Module, Keyword)
-  end.
+dump_binding(Binding, #elixir_scope{vars=Vars}) ->
+  dump_binding(Vars, Binding, []).

-binding_from_vars(#elixir_scope{vars=Vars}, Binding) ->
-  binding_from_vars(Binding, [], Binding, Vars).
-
-binding_from_vars([{Var,_}|T], Acc, Binding, Vars) ->
-  case lists:member($@, atom_to_list(Var)) of
-    true  ->
-      binding_from_vars(T, Acc, Binding, Vars);
-    false ->
-      RealName  = orddict:fetch({ Var, nil }, Vars),
-      RealValue = proplists:get_value(RealName, Binding, nil),
-      binding_from_vars(T, [{Var, RealValue}|Acc], Binding, Vars)
-  end;
-
-binding_from_vars([], Acc, _Binding, _Vars) -> lists:reverse(Acc).
+dump_binding([{{Var,Kind}=Key,InternalName}|T], Binding, Acc) when is_atom(Kind) ->
+  Actual = case Kind of
+    nil -> Var;
+    _   -> Key
+  end,
+  Value = proplists:get_value(InternalName, Binding, nil),
+  dump_binding(T, Binding, orddict:store(Actual, Value, Acc));
+dump_binding([_|T], Binding, Acc) ->
+  dump_binding(T, Binding, Acc);
+dump_binding([], _Binding, Acc) -> Acc.
@@ -3,13 +3,6 @@
 -export([tokenize/3]).
 -import(elixir_interpolation, [unescape_chars/1, unescape_tokens/1]).

-record(scope, {
-  file,
-  terminators=[],
-  check_terminators=true,
-  existing_atoms_only=false
-}).
-
 -define(container(T1, T2),
  T1 == ${, T2 == $};
  T1 == $[, T2 == $]
@@ -96,6 +89,9 @@
 -define(type_op(T1, T2),
  T1 == $:, T2 == $:).

+tokenize(String, Line, #elixir_tokenizer{} = Scope) ->
+  tokenize(String, Line, Scope, []);
+
 tokenize(String, Line, Opts) ->
  File = case lists:keyfind(file, 1, Opts) of
    { file, V1 } -> V1;
@@ -112,21 +108,19 @@ tokenize(String, Line, Opts) ->
    false -> true
  end,

-  Scope = #scope{
+  tokenize(String, Line, #elixir_tokenizer{
    file=File,
    existing_atoms_only=Existing,
    check_terminators=Check
-  },
+  }).

-  tokenize(String, Line, Scope, []).
+tokenize([], Line, #elixir_tokenizer{terminators=[]}, Tokens) ->
+  { ok, Line, lists:reverse(Tokens) };

-tokenize([], _Line, #scope{terminators=[]}, Tokens) ->
-  { ok, lists:reverse(Tokens) };
-
-tokenize([], EndLine, #scope{terminators=[{ Start, StartLine }|_]}, _Tokens) ->
+tokenize([], EndLine, #elixir_tokenizer{terminators=[{ Start, StartLine }|_]}, Tokens) ->
  End     = terminator(Start),
  Message = io_lib:format("missing terminator: ~ts (for \"~ts\" starting at line ~B)", [End, Start, StartLine]),
-  { error, { EndLine, Message, [] } };
+  { error, { EndLine, Message, [] }, [], Tokens };

 % Base integers

@@ -150,69 +144,69 @@ tokenize([$#|String], Line, Scope, Tokens) ->

 % Sigils

-tokenize([$%,S,H,H,H|T], Line, #scope{file=File} = Scope, Tokens) when ?is_quote(H), ?is_upcase(S) orelse ?is_downcase(S) ->
-  case extract_heredoc_with_interpolation(Line, File, ?is_downcase(S), T, H) of
-    { error, _ } = Error ->
-      Error;
+tokenize([$%,S,H,H,H|T] = Original, Line, Scope, Tokens) when ?is_quote(H), ?is_upcase(S) orelse ?is_downcase(S) ->
+  case extract_heredoc_with_interpolation(Line, Scope, ?is_downcase(S), T, H) of
+    { error, Reason } ->
+      { error, Reason, Original, Tokens };
    { Parts, Rest } ->
      { Final, Modifiers } = collect_modifiers(Rest, []),
      tokenize(Final, Line, Scope, [{ sigil, Line, S, Parts, Modifiers }|Tokens])
  end;

-tokenize([$%,S,H|T], Line, #scope{file=File} = Scope, Tokens) when not(?is_identifier(H)), not(?is_terminator(H)), ?is_upcase(S) orelse ?is_downcase(S) ->
-  case elixir_interpolation:extract(Line, File, ?is_downcase(S), T, sigil_terminator(H)) of
+tokenize([$%,S,H|T] = Original, Line, Scope, Tokens) when not(?is_identifier(H)), not(?is_terminator(H)), ?is_upcase(S) orelse ?is_downcase(S) ->
+  case elixir_interpolation:extract(Line, Scope, ?is_downcase(S), T, sigil_terminator(H)) of
    { NewLine, Parts, Rest } ->
      { Final, Modifiers } = collect_modifiers(Rest, []),
      tokenize(Final, NewLine, Scope, [{ sigil, Line, S, Parts, Modifiers }|Tokens]);
-    Error ->
+    { error, Reason } ->
      Sigil = [$%,S,H],
-      interpolation_error(Error, " (for sigil ~ts starting at line ~B)", [Sigil, Line])
+      interpolation_error(Reason, Original, Tokens, " (for sigil ~ts starting at line ~B)", [Sigil, Line])
  end;

 % Char tokens

 tokenize([$?,$\\,P,${,A,B,C,D,E,F,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B), ?is_hex(C), ?is_hex(D), ?is_hex(E), ?is_hex(F) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,B,C,D,E,F,$}]))),
+  Char = escape_char([$\\,P,${,A,B,C,D,E,F,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,${,A,B,C,D,E,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B), ?is_hex(C), ?is_hex(D), ?is_hex(E) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,B,C,D,E,$}]))),
+  Char = escape_char([$\\,P,${,A,B,C,D,E,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,${,A,B,C,D,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B), ?is_hex(C), ?is_hex(D) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,B,C,D,$}]))),
+  Char = escape_char([$\\,P,${,A,B,C,D,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,${,A,B,C,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B), ?is_hex(C) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,B,C,$}]))),
+  Char = escape_char([$\\,P,${,A,B,C,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,${,A,B,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,B,$}]))),
+  Char = escape_char([$\\,P,${,A,B,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,${,A,$}|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,${,A,$}]))),
+  Char = escape_char([$\\,P,${,A,$}]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,A,B|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A), ?is_hex(B) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,A,B]))),
+  Char = escape_char([$\\,P,A,B]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,P,A|T], Line, Scope, Tokens) when (P == $x orelse P == $X), ?is_hex(A) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,P,A]))),
+  Char = escape_char([$\\,P,A]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,A,B,C|T], Line, Scope, Tokens) when ?is_octal(A), A =< $3,?is_octal(B), ?is_octal(C) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,A,B,C]))),
+  Char = escape_char([$\\,A,B,C]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,A,B|T], Line, Scope, Tokens) when ?is_octal(A), ?is_octal(B) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,A,B]))),
+  Char = escape_char([$\\,A,B]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,A|T], Line, Scope, Tokens) when ?is_octal(A) ->
-  [Char] = unicode:characters_to_list(elixir_interpolation:unescape_chars(list_to_binary([$\\,A]))),
+  Char = escape_char([$\\,A]),
  tokenize(T, Line, Scope, [{ number, Line, Char }|Tokens]);

 tokenize([$?,$\\,H|T], Line, Scope, Tokens) ->
@@ -266,18 +260,18 @@ tokenize([$.,T|Rest], Line, Scope, Tokens) when
 tokenize([$.,$(|Rest], Line, Scope, Tokens) ->
  tokenize([$(|Rest], Line, Scope, add_token_with_nl({ dot_call_op, Line, '.' }, Tokens));

-tokenize([$.,H|T], Line, #scope{file=File} = Scope, Tokens) when ?is_quote(H) ->
-  case elixir_interpolation:extract(Line, File, true, T, H) of
+tokenize([$.,H|T] = Original, Line, Scope, Tokens) when ?is_quote(H) ->
+  case elixir_interpolation:extract(Line, Scope, true, T, H) of
    { NewLine, [Part], Rest } when is_binary(Part) ->
      case unsafe_to_atom(Part, Line, Scope) of
-        { error, _ } = Error ->
-          Error;
-        Atom ->
+        { ok, Atom } ->
          Token = check_call_identifier(identifier, Line, Atom, Rest),
-          tokenize(Rest, NewLine, Scope, [Token|add_token_with_nl({ '.', Line }, Tokens)])
+          tokenize(Rest, NewLine, Scope, [Token|add_token_with_nl({ '.', Line }, Tokens)]);
+        { error, Reason } ->
+          { error, Reason, Original, Tokens }
      end;
-    Error ->
-      interpolation_error(Error, " (for function name starting at line ~B)", [Line])
+    { error, Reason } ->
+      interpolation_error(Reason, Original, Tokens, " (for function name starting at line ~B)", [Line])
  end;

 % Heredocs
@@ -297,30 +291,23 @@ tokenize([$'|T], Line, Scope, Tokens) ->

 % Atoms

-tokenize([$:,H|T], Line, #scope{file=File} = Scope, Tokens) when ?is_quote(H) ->
-  case elixir_interpolation:extract(Line, File, true, T, H) of
+tokenize([$:,H|T] = Original, Line, Scope, Tokens) when ?is_quote(H) ->
+  case elixir_interpolation:extract(Line, Scope, true, T, H) of
    { NewLine, Parts, Rest } ->
-      SafeAtom = case unescape_tokens(Parts) of
-        [Part] when is_list(Part) or is_binary(Part) -> unsafe_to_atom(Part, Line, Scope);
-        Unescaped -> Unescaped
-      end,
-      case SafeAtom of
-        { error, _ } = Error ->
-          Error;
-        Atom ->
-          tokenize(Rest, NewLine, Scope, [{ atom, Line, Atom }|Tokens])
-      end;
-    Error ->
-      interpolation_error(Error, " (for atom starting at line ~B)", [Line])
+      Unescaped = unescape_tokens(Parts),
+      ExistingAtomsOnly = Scope#elixir_tokenizer.existing_atoms_only,
+      tokenize(Rest, NewLine, Scope, [{ atom_string, Line, ExistingAtomsOnly, Unescaped }|Tokens]);
+    { error, Reason } ->
+      interpolation_error(Reason, Original, Tokens, " (for atom starting at line ~B)", [Line])
  end;

-tokenize([$:,T|String], Line, Scope, Tokens) when ?is_atom_start(T) ->
+tokenize([$:,T|String] = Original, Line, Scope, Tokens) when ?is_atom_start(T) ->
  { Rest, Part } = tokenize_atom([T|String], []),
  case unsafe_to_atom(Part, Line, Scope) of
-    { error, _ } = Error ->
-      Error;
-    Atom ->
-      tokenize(Rest, Line, Scope, [{ atom, Line, Atom }|Tokens])
+    { ok, Atom } ->
+      tokenize(Rest, Line, Scope, [{ atom, Line, Atom }|Tokens]);
+    { error, Reason } ->
+      { error, Reason, Original, Tokens }
  end;

 % Atom identifiers/operators
@@ -474,18 +461,18 @@ tokenize([H|_] = String, Line, Scope, Tokens) when ?is_digit(H) ->

 % Aliases

-tokenize([H|_] = String, Line, Scope, Tokens) when ?is_upcase(H) ->
-  { Rest, Alias } = tokenize_identifier(String, []),
+tokenize([H|_] = Original, Line, Scope, Tokens) when ?is_upcase(H) ->
+  { Rest, Alias } = tokenize_identifier(Original, []),
  case unsafe_to_atom(Alias, Line, Scope) of
-    { error, _ } = Error ->
-      Error;
-    Atom ->
+    { ok, Atom } ->
      case Rest of
        [$:|T] when ?is_space(hd(T)) ->
          tokenize(T, Line, Scope, [{ kw_identifier, Line, Atom }|Tokens]);
        _ ->
          tokenize(Rest, Line, Scope, [{ aliases, Line, [Atom] }|Tokens])
-      end
+      end;
+    { error, Reason } ->
+      { error, Reason, Original, Tokens }
  end;

 % Identifier
@@ -496,7 +483,7 @@ tokenize([H|_] = String, Line, Scope, Tokens) when ?is_downcase(H); H == $_ ->
      handle_terminator(Rest, Line, Scope, Check, T);
    { identifier, Rest, Token } ->
      tokenize(Rest, Line, Scope, [Token|Tokens]);
-    { error, _ } = Error ->
+    { error, _, _, _ } = Error ->
      Error
  end;

@@ -519,44 +506,48 @@ tokenize([T|Rest], Line, Scope, Tokens) when ?is_horizontal_space(T) ->
 tokenize([{line,Line}|Rest], _Line, Scope, Tokens) ->
  tokenize(Rest, Line, Scope, Tokens);

-tokenize(T, Line, _Scope, _Tokens) ->
-  { error, { Line, "invalid token: ", until_eol(T) } }.
+tokenize(T, Line, _Scope, Tokens) ->
+  { error, { Line, "invalid token: ", until_eol(T) }, T, Tokens }.

 until_eol("\r\n" ++ _) -> [];
 until_eol("\n" ++ _)   -> [];
 until_eol([])          -> [];
 until_eol([H|T])       -> [H|until_eol(T)].

+escape_char(List) ->
+  << Char/utf8 >> = elixir_interpolation:unescape_chars(list_to_binary(List)),
+  Char.
+
 %% Handlers

-handle_heredocs(T, Line, H, #scope{file=File} = Scope, Tokens) ->
-  case extract_heredoc_with_interpolation(Line, File, true, T, H) of
-    { error, _ } = Error ->
-      Error;
+handle_heredocs(T, Line, H, Scope, Tokens) ->
+  case extract_heredoc_with_interpolation(Line, Scope, true, T, H) of
+    { error, Reason } ->
+      { error, Reason, [H, H, H] ++ T, Tokens };
    { Parts, Rest } ->
      Token = { string_type(H), Line, unescape_tokens(Parts) },
      tokenize(Rest, Line, Scope, [Token|Tokens])
  end.

-handle_strings(T, Line, H, #scope{file=File} = Scope, Tokens) ->
-  case elixir_interpolation:extract(Line, File, true, T, H) of
+handle_strings(T, Line, H, Scope, Tokens) ->
+  case elixir_interpolation:extract(Line, Scope, true, T, H) of
+    { error, Reason } ->
+      interpolation_error(Reason, [H|T], Tokens, " (for string starting at line ~B)", [Line]);
    { NewLine, Parts, [$:|Rest] } when ?is_space(hd(Rest)) ->
      case Parts of
        [Bin] when is_binary(Bin) ->
          case unsafe_to_atom(unescape_chars(Bin), Line, Scope) of
-            { error, _ } = Error ->
-              Error;
-            Atom ->
-              tokenize(Rest, NewLine, Scope, [{ kw_identifier, Line, Atom }|Tokens])
+            { ok, Atom } ->
+              tokenize(Rest, NewLine, Scope, [{ kw_identifier, Line, Atom }|Tokens]);
+            { error, Reason } ->
+              { error, Reason, [H|T], Tokens }
          end;
        _ ->
-          { error, { Line, "invalid interpolation in key ", [$"|T] } }
+          { error, { Line, "invalid interpolation in key ", [$"|T] }, [H|T], Tokens }
      end;
    { NewLine, Parts, Rest } ->
      Token = { string_type(H), Line, unescape_tokens(Parts) },
-      tokenize(Rest, NewLine, Scope, [Token|Tokens]);
-    Error ->
-      interpolation_error(Error, " (for string starting at line ~B)", [Line])
+      tokenize(Rest, NewLine, Scope, [Token|Tokens])
  end.

 handle_nonl_op([$:|Rest], Line, _Kind, Op, Scope, Tokens) when ?is_space(hd(Rest)) ->
@@ -581,18 +572,18 @@ eol(_Line, _Mod, [{',',_}|_] = Tokens)   -> Tokens;
 eol(_Line, _Mod, [{eol,_,_}|_] = Tokens) -> Tokens;
 eol(Line, Mod, Tokens) -> [{eol,Line,Mod}|Tokens].

-unsafe_to_atom(Part, Line, #scope{}) when
+unsafe_to_atom(Part, Line, #elixir_tokenizer{}) when
    is_binary(Part) andalso size(Part) > 255;
    is_list(Part) andalso length(Part) > 255 ->
  { error, { Line, "atom length must be less than system limit", ":" } };
-unsafe_to_atom(Binary, _Line, #scope{existing_atoms_only=true}) when is_binary(Binary) ->
-  binary_to_existing_atom(Binary, utf8);
-unsafe_to_atom(Binary, _Line, #scope{}) when is_binary(Binary) ->
-  binary_to_atom(Binary, utf8);
-unsafe_to_atom(List, _Line, #scope{existing_atoms_only=true}) when is_list(List) ->
-  list_to_existing_atom(List);
-unsafe_to_atom(List, _Line, #scope{}) when is_list(List) ->
-  list_to_atom(List).
+unsafe_to_atom(Binary, _Line, #elixir_tokenizer{existing_atoms_only=true}) when is_binary(Binary) ->
+  { ok, binary_to_existing_atom(Binary, utf8) };
+unsafe_to_atom(Binary, _Line, #elixir_tokenizer{}) when is_binary(Binary) ->
+  { ok, binary_to_atom(Binary, utf8) };
+unsafe_to_atom(List, _Line, #elixir_tokenizer{existing_atoms_only=true}) when is_list(List) ->
+  { ok, list_to_existing_atom(List) };
+unsafe_to_atom(List, _Line, #elixir_tokenizer{}) when is_list(List) ->
+  { ok, list_to_atom(List) }.

 collect_modifiers([H|T], Buffer) when ?is_downcase(H) ->
  collect_modifiers(T, [H|Buffer]);
@@ -602,14 +593,16 @@ collect_modifiers(Rest, Buffer) ->

 %% Heredocs

-extract_heredoc_with_interpolation(Line, File, Interpol, T, H) ->
+extract_heredoc_with_interpolation(Line, Scope, Interpol, T, H) ->
  case extract_heredoc(Line, T, H) of
    { error, _ } = Error ->
      Error;
    { Body, Rest } ->
-      case elixir_interpolation:extract(Line + 1, File, Interpol, Body, 0) of
-        { _, Parts, [] } -> { Parts, Rest };
-        Error -> interpolation_error(Error, " (for heredoc starting at line ~B)", [Line])
+      case elixir_interpolation:extract(Line + 1, Scope, Interpol, Body, 0) of
+        { error, Reason } ->
+          { error, interpolation_format(Reason, " (for heredoc starting at line ~B)", [Line]) };
+        { _, Parts, [] } ->
+          { Parts, Rest }
      end
  end.

@@ -658,6 +651,9 @@ remove_heredoc_spaces([], Buffer, _Spaces, _Original) ->
 %% the remaining of the document and the number of spaces the heredoc
 %% is aligned.

+extract_heredoc_body(_Line, Marker, [{line,NewLine}|Rest], Buffer) ->
+  extract_heredoc_body(NewLine, Marker, Rest, Buffer);
+
 extract_heredoc_body(Line, Marker, Rest, Buffer) ->
  case extract_heredoc_line(Marker, Rest, Buffer, 0) of
    { ok, NewBuffer, NewRest } ->
@@ -784,8 +780,8 @@ tokenize_identifier(Rest, Acc) ->

 %% Tokenize any identifier, handling kv, punctuated, paren, bracket and do identifiers.

-tokenize_any_identifier(String, Line, Scope, Tokens) ->
-  { Rest, Identifier } = tokenize_identifier(String, []),
+tokenize_any_identifier(Original, Line, Scope, Tokens) ->
+  { Rest, Identifier } = tokenize_identifier(Original, []),

  { AllIdentifier, AllRest } =
    case Rest of
@@ -794,17 +790,19 @@ tokenize_any_identifier(String, Line, Scope, Tokens) ->
    end,

  case unsafe_to_atom(AllIdentifier, Line, Scope) of
-    { error, _ } = Error ->
-      Error;
-    Atom ->
-      tokenize_kw_or_other(AllRest, identifier, Line, Atom, Tokens)
+    { ok, Atom } ->
+      tokenize_kw_or_other(AllRest, identifier, Line, Atom, Tokens);
+    { error, Reason } ->
+      { error, Reason, Original, Tokens }
  end.

 tokenize_kw_or_other([$:,H|T], _Kind, Line, Atom, _Tokens) when ?is_space(H) ->
  { identifier, [H|T], { kw_identifier, Line, Atom } };

-tokenize_kw_or_other([$:,H|_], _Kind, Line, Atom, _Tokens) when ?is_atom_start(H) ->
-  { error, { Line, "keyword argument must be followed by space after: ", atom_to_list(Atom) ++ [$:] } };
+tokenize_kw_or_other([$:,H|T], _Kind, Line, Atom, Tokens) when ?is_atom_start(H) ->
+  Original = atom_to_list(Atom) ++ [$:],
+  Reason   = { Line, "keyword argument must be followed by space after: ", Original },
+  { error, Reason, Original ++ [H|T], Tokens };

 tokenize_kw_or_other(Rest, Kind, Line, Atom, Tokens) ->
  case check_keyword(Line, Atom, Tokens) of
@@ -813,7 +811,7 @@ tokenize_kw_or_other(Rest, Kind, Line, Atom, Tokens) ->
    { ok, [Check|T] } ->
      { keyword, Rest, Check, T };
    { error, Token } ->
-      { error, { Line, "syntax error before: ", Token } }
+      { error, { Line, "syntax error before: ", Token }, atom_to_list(Atom) ++ Rest, Tokens }
  end.

 %% Check if it is a call identifier (paren | bracket | do)
@@ -827,23 +825,30 @@ add_token_with_nl(Left, T) -> [Left|T].

 %% Error handling

-interpolation_error({ error, { Line, Message, Token } }, Extension, Args) ->
-  { error, { Line, io_lib:format("~ts" ++ Extension, [Message|Args]), Token } }.
+interpolation_error(Reason, Rest, Tokens, Extension, Args) ->
+  { error, interpolation_format(Reason, Extension, Args), Rest, Tokens }.
+
+interpolation_format({ string, Line, Message, Token }, Extension, Args) ->
+  { Line, io_lib:format("~ts" ++ Extension, [Message|Args]), Token };
+interpolation_format({ _, _, _ } = Reason, _Extension, _Args) ->
+  Reason.

 %% Terminators

 handle_terminator(Rest, Line, Scope, Token, Tokens) ->
  case handle_terminator(Token, Scope) of
-    { error, _ } = Error -> Error;
-    New -> tokenize(Rest, Line, New, [Token|Tokens])
+    { error, Reason } ->
+      { error, Reason, atom_to_list(element(1, Token)) ++ Rest, Tokens };
+    New ->
+      tokenize(Rest, Line, New, [Token|Tokens])
  end.

-handle_terminator(_, #scope{check_terminators=false} = Scope) ->
+handle_terminator(_, #elixir_tokenizer{check_terminators=false} = Scope) ->
  Scope;
-handle_terminator(Token, #scope{terminators=Terminators} = Scope) ->
+handle_terminator(Token, #elixir_tokenizer{terminators=Terminators} = Scope) ->
  case check_terminator(Token, Terminators) of
    { error, _ } = Error -> Error;
-    New -> Scope#scope{terminators=New}
+    New -> Scope#elixir_tokenizer{terminators=New}
  end.

 check_terminator({ S, Line }, Terminators) when S == 'fn' ->
@@ -1,14 +1,12 @@
-%% Module responsible for tracking invocations of locals,
-%% imports and requires.
+%% Module responsible for tracking invocations of module calls.
 -module(elixir_tracker).
 -export([
  setup/1, cleanup/1,
  record_local/2, record_local/3,
  record_import/4, record_remote/4,
-  record_warn/4, record_definition/3,
-  record_defaults/4, record_alias/2,
-  ensure_no_function_conflict/4, ensure_all_imports_used/3,
-  warn_unused_local/3, format_error/1
+  record_definition/3, record_defaults/4,
+  ensure_no_function_conflict/4, warn_unused_local/3,
+  format_error/1
 ]).
 -include("elixir.hrl").

@@ -18,9 +16,9 @@
 %% RECORD

 setup(Module) ->
-  case code:ensure_loaded(?tracker) of
-    { module, _ } -> ets:insert(Module, { ?attr, ?tracker:start_link() });
-    { error, _ }  -> ok
+  case code:is_loaded(?tracker) of
+    { file, _ } -> ets:insert(Module, { ?attr, ?tracker:start_link() });
+    false -> ok
  end.

 cleanup(Module) ->
@@ -39,40 +37,21 @@ record_local(Tuple, Module, Function) ->
    true
  end).

-record_warn(Ref, Warn, Line, Module) ->
-  if_tracker(Module, fun(Pid) ->
-    ?tracker:add_warnable(Pid, Ref, Warn, Line),
-    true
-  end).
-
 record_import(_Tuple, Receiver, Module, _Function)
  when Module == nil; Module == Receiver -> false;
 record_import(Tuple, Receiver, Module, Function) ->
-  try
-    Pid = ets:lookup_element(Module, ?attr, 2),
-    ?tracker:add_import(Pid, Function, Receiver, Tuple)
-  catch
-    error:badarg -> false
-  end.
+  if_tracker(Module, fun(Pid) ->
+    ?tracker:add_import(Pid, Function, Receiver, Tuple),
+    true
+  end).

 record_remote(_Tuple, Receiver, Module, _Function)
  when Module == nil; Module == Receiver -> false;
 record_remote(Tuple, Receiver, Module, Function) ->
-  try
-    Pid = ets:lookup_element(Module, ?attr, 2),
-    ?tracker:add_remote(Pid, Function, Receiver, Tuple)
-  catch
-    error:badarg -> false
-  end.
-
-record_alias(_Receiver, nil) -> false;
-record_alias(Receiver, Module) ->
-  try
-    Pid = ets:lookup_element(Module, ?attr, 2),
-    ?tracker:add_alias(Pid, Receiver)
-  catch
-    error:badarg -> false
-  end.
+  if_tracker(Module, fun(Pid) ->
+    ?tracker:add_remote(Pid, Function, Receiver, Tuple),
+    true
+  end).

 record_definition(Tuple, Kind, Module) ->
  if_tracker(Module, fun(Pid) ->
@@ -91,9 +70,10 @@ record_defaults(Tuple, Kind, Module, Defaults) ->
 %% HELPERS

 if_tracker(Module, Callback) ->
-  case ets:lookup(Module, ?attr) of
-    [{ ?attr, Pid }] -> Callback(Pid);
-    _ -> false
+  try ets:lookup_element(Module, ?attr, 2) of
+    Pid -> Callback(Pid)
+  catch
+    error:badarg -> false
  end.

 %% ERROR HANDLING
@@ -106,14 +86,6 @@ ensure_no_function_conflict(Meta, File, Module, AllDefined) ->
  end),
  ok.

-ensure_all_imports_used(_Line, File, Module) ->
-  if_tracker(Module, fun(Pid) ->
-    [ begin
-        elixir_errors:handle_file_warning(File, { L, ?MODULE, { unused_import, M } })
-      end || { M, L } <- ?tracker:collect_unused_imports(Pid)]
-  end),
-  ok.
-
 warn_unused_local(File, Module, Private) ->
  if_tracker(Module, fun(Pid) ->
    Args = [ { Fun, Kind, Defaults } ||
@@ -131,9 +103,6 @@ format_error({function_conflict,{Receivers, Name, Arity}}) ->
  io_lib:format("imported ~ts.~ts/~B conflicts with local function",
    [elixir_errors:inspect(hd(Receivers)), Name, Arity]);

-format_error({unused_import, Module}) ->
-  io_lib:format("unused import ~ts", [elixir_errors:inspect(Module)]);
-
 format_error({unused_args,{Name, Arity}}) ->
  io_lib:format("default arguments in ~ts/~B are never used", [Name, Arity]);

@@ -2,8 +2,7 @@
 %% overriden are defined in this file.
 -module(elixir_translator).
 -export([forms/4, 'forms!'/4]).
-export([translate/2, translate_each/2, translate_arg/2,
-         translate_args/2, translate_apply/7]).
+-export([translate/2, translate_each/2, translate_arg/2, translate_args/2]).
 -import(elixir_scope, [umergev/2, umergec/2, umergea/2]).
 -import(elixir_errors, [syntax_error/3, syntax_error/4,
  compile_error/3, compile_error/4,
@@ -12,17 +11,15 @@
 -include("elixir.hrl").

 forms(String, StartLine, File, Opts) ->
-  try elixir_tokenizer:tokenize(String, StartLine, [{ file, File }|Opts]) of
-    { ok, Tokens } ->
+  case elixir_tokenizer:tokenize(String, StartLine, [{ file, File }|Opts]) of
+    { ok, _Line, Tokens } ->
      try elixir_parser:parse(Tokens) of
        { ok, Forms } -> { ok, Forms };
        { error, { Line, _, [Error, Token] } } -> { error, { Line, Error, Token } }
      catch
        { error, { Line, _, [Error, Token] } } -> { error, { Line, Error, Token } }
      end;
-    { error, { _, _, _ } } = Else -> Else
-  catch
-    { interpolation_error, { _, _, _ } = Tuple} -> { error, Tuple }
+    { error, Reason, _Rest, _SoFar  } -> { error, Reason }
  end.

 'forms!'(String, StartLine, File, Opts) ->
@@ -36,10 +33,6 @@ forms(String, StartLine, File, Opts) ->
 translate(Forms, S) ->
  lists:mapfoldl(fun translate_each/2, S, Forms).

-%% Those macros are "low-level". They are the basic mechanism
-%% that makes the language work and cannot be partially applied
-%% nor overwritten.
-
 %% Assignment operator

 translate_each({ '=', Meta, [Left, Right] }, S) ->
@@ -50,7 +43,7 @@ translate_each({ '=', Meta, [Left, Right] }, S) ->

 %% Containers

-translate_each({ C, _, _ } = Original, S) when C == '[]'; C == '{}'; C == '<<>>' ->
+translate_each({ C, _, _ } = Original, S) when C == '{}'; C == '<<>>' ->
  elixir_literal:translate(Original, S);

 %% Blocks and scope rewriters
@@ -89,7 +82,7 @@ translate_each({ alias, Meta, [Ref] }, S) ->
 translate_each({ alias, Meta, [Ref, KV] }, S) ->
  assert_no_match_or_guard_scope(Meta, alias, S),
  { TRef, SR } = translate_each(Ref, S),
-  { TKV, ST }  = translate_opts(Meta, alias, [as], no_alias_opts(KV), SR),
+  { TKV, ST }  = translate_opts(Meta, alias, [as, warn], no_alias_opts(KV), SR),

  case TRef of
    { atom, _, Old } ->
@@ -105,7 +98,7 @@ translate_each({ require, Meta, [Ref, KV] }, S) ->
  assert_no_match_or_guard_scope(Meta, require, S),

  { TRef, SR } = translate_each(Ref, S),
-  { TKV, ST }  = translate_opts(Meta, require, [as], no_alias_opts(KV), SR),
+  { TKV, ST }  = translate_opts(Meta, require, [as, warn], no_alias_opts(KV), SR),

  case TRef of
    { atom, _, Old } ->
@@ -145,7 +138,7 @@ translate_each({ '__DIR__', _Meta, Atom }, S) when is_atom(Atom) ->

 translate_each({ '__ENV__', Meta, Atom }, S) when is_atom(Atom) ->
  Env = elixir_scope:to_ex_env({ ?line(Meta), S }),
-  { elixir_utils:elixir_to_erl(Env), S };
+  { elixir_scope:to_erl(Env), S };

 translate_each({ '__CALLER__', Meta, Atom }, S) when is_atom(Atom) ->
  { { var, ?line(Meta), '__CALLER__' }, S#elixir_scope{caller=true} };
@@ -153,9 +146,9 @@ translate_each({ '__CALLER__', Meta, Atom }, S) when is_atom(Atom) ->
 %% Aliases

 translate_each({ '__aliases__', Meta, _ } = Alias, S) ->
-  case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases) of
+  case elixir_aliases:expand(Alias, S#elixir_scope.aliases, S#elixir_scope.macro_aliases, S#elixir_scope.lexical_tracker) of
    Receiver when is_atom(Receiver) ->
-      elixir_tracker:record_alias(Receiver, S#elixir_scope.module),
+      elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
      { { atom, ?line(Meta), Receiver }, S };
    Aliases ->
      { TAliases, SA } = translate_args(Aliases, S),
@@ -164,7 +157,7 @@ translate_each({ '__aliases__', Meta, _ } = Alias, S) ->
        true ->
          Atoms = [Atom || { atom, _, Atom } <- TAliases],
          Receiver = elixir_aliases:concat(Atoms),
-          elixir_tracker:record_alias(Receiver, S#elixir_scope.module),
+          elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
          { { atom, ?line(Meta), Receiver }, SA };
        false ->
          Args = [elixir_utils:list_to_cons(?line(Meta), TAliases)],
@@ -287,7 +280,7 @@ translate_each({ '&', Meta, [Arg] }, S) ->
  assert_no_match_or_guard_scope(Meta, '&', S),
  elixir_fn:capture(Meta, Arg, S);

-translate_each({ fn, Meta, [[{do, { '->', _, Pairs }}]] }, S) ->
+translate_each({ fn, Meta, [{ '->', _, Pairs }] }, S) ->
  assert_no_match_or_guard_scope(Meta, 'fn', S),
  elixir_fn:fn(Meta, Pairs, S);

@@ -296,30 +289,26 @@ translate_each({ fn, Meta, [[{do, { '->', _, Pairs }}]] }, S) ->
 translate_each({ Kind, Meta, Args }, S) when is_list(Args), (Kind == lc) orelse (Kind == bc) ->
  translate_comprehension(Meta, Kind, Args, S);

-%% Super (exceptionally supports partial application)
+%% Super

-translate_each({ super, Meta, Args } = Original, S) when is_list(Args) ->
-  case elixir_partials:handle(Original, S) of
-    error ->
-      assert_no_match_or_guard_scope(Meta, super, S),
-      Module = assert_module_scope(Meta, super, S),
-      Function = assert_function_scope(Meta, super, S),
-      elixir_def_overridable:ensure_defined(Meta, Module, Function, S),
+translate_each({ super, Meta, Args }, S) when is_list(Args) ->
+  assert_no_match_or_guard_scope(Meta, super, S),
+  Module = assert_module_scope(Meta, super, S),
+  Function = assert_function_scope(Meta, super, S),
+  elixir_def_overridable:ensure_defined(Meta, Module, Function, S),

-      { _, Arity } = Function,
+  { _, Arity } = Function,

-      { TArgs, TS } = if
-        length(Args) == Arity ->
-          translate_args(Args, S);
-        true ->
-          syntax_error(Meta, S#elixir_scope.file, "super must be called with the same number of "
-                       "arguments as the current function")
-      end,
+  { TArgs, TS } = if
+    length(Args) == Arity ->
+      translate_args(Args, S);
+    true ->
+      syntax_error(Meta, S#elixir_scope.file, "super must be called with the same number of "
+                   "arguments as the current function")
+  end,

-      Super = elixir_def_overridable:name(Module, Function),
-      { { call, ?line(Meta), { atom, ?line(Meta), Super }, TArgs }, TS#elixir_scope{super=true} };
-    Else -> Else
-  end;
+  Super = elixir_def_overridable:name(Module, Function),
+  { { call, ?line(Meta), { atom, ?line(Meta), Super }, TArgs }, TS#elixir_scope{super=true} };

 translate_each({ 'super?', Meta, [] }, S) ->
  Module = assert_module_scope(Meta, 'super?', S),
@@ -329,9 +318,9 @@ translate_each({ 'super?', Meta, [] }, S) ->

 %% Variables

-translate_each({ '^', Meta, [ { Name, _, Kind } = Var ] },
+translate_each({ '^', Meta, [ { Name, VarMeta, Kind } = Var ] },
               #elixir_scope{extra=fn_match, extra_guards=Extra} = S) when is_atom(Name), is_atom(Kind) ->
-  case orddict:find({ Name, Kind }, S#elixir_scope.backup_vars) of
+  case orddict:find({ Name, var_kind(VarMeta, Kind) }, S#elixir_scope.backup_vars) of
    { ok, Value } ->
      Line = ?line(Meta),
      { TVar, TS } = translate_each(Var, S),
@@ -341,8 +330,8 @@ translate_each({ '^', Meta, [ { Name, _, Kind } = Var ] },
      compile_error(Meta, S#elixir_scope.file, "unbound variable ^~ts", [Name])
  end;

-translate_each({ '^', Meta, [ { Name, _, Kind } ] }, #elixir_scope{context=match} = S) when is_atom(Name), is_atom(Kind) ->
-  case orddict:find({ Name, Kind }, S#elixir_scope.backup_vars) of
+translate_each({ '^', Meta, [ { Name, VarMeta, Kind } ] }, #elixir_scope{context=match} = S) when is_atom(Name), is_atom(Kind) ->
+  case orddict:find({ Name, var_kind(VarMeta, Kind) }, S#elixir_scope.backup_vars) of
    { ok, Value } ->
      { { var, ?line(Meta), Value }, S };
    error ->
@@ -358,7 +347,7 @@ translate_each({ '^', Meta, [ Expr ] }, S) ->
    "the unary operator ^ can only be used with variables, invalid expression ^~ts", ['Elixir.Macro':to_string(Expr)]);

 translate_each({ Name, Meta, Kind }, S) when is_atom(Name), is_atom(Kind) ->
-  elixir_scope:translate_var(Meta, Name, Kind, S, fun() ->
+  elixir_scope:translate_var(Meta, Name, var_kind(Meta, Kind), S, fun() ->
    translate_each({ Name, Meta, [] }, S)
  end);

@@ -367,101 +356,99 @@ translate_each({ Name, Meta, Kind }, S) when is_atom(Name), is_atom(Kind) ->
 translate_each({ '->', Meta, _Args }, S) ->
  syntax_error(Meta, S#elixir_scope.file, "unhandled operator ->");

-translate_each({ Atom, Meta, Args } = Original, S) when is_atom(Atom) ->
+translate_each({ Atom, Meta, Args }, S) when is_atom(Atom), is_list(Meta), is_list(Args) ->
  assert_no_ambiguous_op(Atom, Meta, Args, S),

-  case elixir_partials:is_sequential(Args) andalso
-       elixir_dispatch:import_function(Meta, Atom, length(Args), S) of
-    false ->
-      case elixir_partials:handle(Original, S) of
-        error ->
-          Callback = fun() ->
-            case S#elixir_scope.context of
-              match ->
-                compile_error(Meta, S#elixir_scope.file,
-                              "cannot invoke function ~ts/~B inside match", [Atom, length(Args)]);
-              guard ->
-                Arity = length(Args),
-                File  = S#elixir_scope.file,
-                case Arity of
-                  0 -> compile_error(Meta, File, "unknown variable ~ts or cannot invoke "
-                                     "function ~ts/~B inside guard", [Atom, Atom, Arity]);
-                  _ -> compile_error(Meta, File, "cannot invoke local ~ts/~B inside guard",
-                                     [Atom, Arity])
-                end;
-              _ ->
-                translate_local(Meta, Atom, Args, S)
-            end
-          end,
+  Callback = fun() ->
+    case S#elixir_scope.context of
+      match ->
+        compile_error(Meta, S#elixir_scope.file,
+                      "cannot invoke function ~ts/~B inside match", [Atom, length(Args)]);
+      guard ->
+        Arity = length(Args),
+        File  = S#elixir_scope.file,
+        case Arity of
+          0 -> compile_error(Meta, File, "unknown variable ~ts or cannot invoke "
+                             "function ~ts/~B inside guard", [Atom, Atom, Arity]);
+          _ -> compile_error(Meta, File, "cannot invoke local ~ts/~B inside guard",
+                             [Atom, Arity])
+        end;
+      _ ->
+        translate_local(Meta, Atom, Args, S)
+    end
+  end,

-          elixir_dispatch:dispatch_import(Meta, Atom, Args, S, Callback);
-        Else  -> Else
-      end;
-    Else -> Else
-  end;
+  elixir_dispatch:dispatch_import(Meta, Atom, Args, S, Callback);

 %% Remote calls

-translate_each({ { '.', _, [Left, Right] }, Meta, Args } = Original, S) when is_atom(Right) ->
+translate_each({ { '.', _, [Left, Right] }, Meta, Args }, S)
+    when (is_tuple(Left) orelse is_atom(Left)), is_atom(Right), is_list(Meta), is_list(Args) ->
  { TLeft,  SL } = translate_each(Left, S),
+  { TRight, SR } = translate_each(Right, umergec(S, SL)),

-  Fun = (element(1, TLeft) == atom) andalso elixir_partials:is_sequential(Args) andalso
-    elixir_dispatch:require_function(Meta, element(3, TLeft), Right, length(Args), SL),
+  Callback = fun() ->
+    case TLeft of
+      { atom, _, Receiver } ->
+        Tuple = { element(3, TRight), length(Args) },
+        elixir_lexical:record_remote(Receiver, S#elixir_scope.lexical_tracker),
+        elixir_tracker:record_remote(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function);
+      _ ->
+        ok
+    end,

-  case Fun of
-    false ->
-      case elixir_partials:handle(Original, S) of
-        error ->
-          { TRight, SR } = translate_each(Right, umergec(S, SL)),
-          Callback = fun() -> translate_apply(Meta, TLeft, TRight, Args, S, SL, SR) end,
+    Line = ?line(Meta),
+    { TArgs, SA } = translate_args(Args, umergec(S, SR)),
+    { { call, Line, { remote, Line, TLeft, TRight }, TArgs }, umergev(SL, umergev(SR, SA)) }
+  end,

-          case TLeft of
-            { atom, _, Receiver } ->
-              elixir_dispatch:dispatch_require(Meta, Receiver, Right, Args, umergev(SL, SR), fun() ->
-                case S#elixir_scope.context of
-                  Context when Receiver /= erlang, (Context == match) orelse (Context == guard) ->
-                    compile_error(Meta, S#elixir_scope.file, "cannot invoke remote function ~ts.~ts/~B inside ~ts",
-                      [elixir_errors:inspect(Receiver), Right, length(Args), Context]);
-                  _ ->
-                    Callback()
-                end
-              end);
-            _ ->
-              case S#elixir_scope.context of
-                Context when Context == match; Context == guard ->
-                  compile_error(Meta, S#elixir_scope.file, "cannot invoke remote function ~ts/~B inside ~ts",
-                    [Right, length(Args), Context]);
-                _ ->
-                  Callback()
-              end
-          end;
-        Else -> Else
-      end;
-    Else -> Else
+  case TLeft of
+    { atom, _, Receiver } ->
+      elixir_dispatch:dispatch_require(Meta, Receiver, Right, Args, umergev(SL, SR), fun() ->
+        case S#elixir_scope.context of
+          Context when Receiver /= erlang, (Context == match) orelse (Context == guard) ->
+            compile_error(Meta, S#elixir_scope.file, "cannot invoke remote function ~ts.~ts/~B inside ~ts",
+              [elixir_errors:inspect(Receiver), Right, length(Args), Context]);
+          _ ->
+            Callback()
+        end
+      end);
+    _ ->
+      case S#elixir_scope.context of
+        Context when Context == match; Context == guard ->
+          compile_error(Meta, S#elixir_scope.file, "cannot invoke remote function ~ts/~B inside ~ts",
+            [Right, length(Args), Context]);
+        _ ->
+          Callback()
+      end
  end;

 %% Anonymous function calls

-translate_each({ { '.', _, [Expr] }, Meta, Args } = Original, S) ->
+translate_each({ { '.', _, [Expr] }, Meta, Args }, S) when is_list(Args) ->
  { TExpr, SE } = translate_each(Expr, S),
  case TExpr of
    { atom, _, Atom } ->
      syntax_error(Meta, S#elixir_scope.file, "invalid function call :~ts.()", [Atom]);
    _ ->
-      case elixir_partials:handle(Original, S) of
-        error ->
-          { TArgs, SA } = translate_args(Args, umergec(S, SE)),
-          { {call, ?line(Meta), TExpr, TArgs}, umergev(SE, SA) };
-        Else -> Else
-      end
+      { TArgs, SA } = translate_args(Args, umergec(S, SE)),
+      { {call, ?line(Meta), TExpr, TArgs}, umergev(SE, SA) }
  end;

 %% Invalid calls

-translate_each({ Invalid, Meta, _Args }, S) ->
-  syntax_error(Meta, S#elixir_scope.file, "unexpected parenthesis after ~ts",
+translate_each({ { '.', _, [Invalid, _] }, Meta, Args }, S) when is_list(Meta) and is_list(Args) ->
+  syntax_error(Meta, S#elixir_scope.file, "invalid remote call on ~ts",
    ['Elixir.Macro':to_string(Invalid)]);

+translate_each({ _, Meta, Args } = Invalid, S) when is_list(Meta) and is_list(Args) ->
+  syntax_error(Meta, S#elixir_scope.file, "invalid call ~ts",
+    ['Elixir.Macro':to_string(Invalid)]);
+
+translate_each({ _, _, _ } = Tuple, S) ->
+  syntax_error([{line,0}], S#elixir_scope.file, "expected a valid quoted expression, got: ~ts",
+    ['Elixir.Kernel':inspect(Tuple, [{raw,true}])]);
+
 %% Literals

 translate_each(Literal, S) ->
@@ -469,6 +456,12 @@ translate_each(Literal, S) ->

 %% Helpers

+var_kind(Meta, Kind) ->
+  case lists:keyfind(counter, 1, Meta) of
+    { counter, Counter } -> Counter;
+    false -> Kind
+  end.
+
 %% Opts

 translate_opts(Meta, Kind, Allowed, Opts, S) ->
@@ -542,7 +535,7 @@ translate_alias(Meta, IncludeByDefault, Old, TKV, S) ->
               "invalid :as for alias, nested alias ~s not allowed", [elixir_errors:inspect(New)])
  end,

-  { { atom, ?line(Meta), nil }, elixir_aliases:store(Meta, New, Old, S) }.
+  { { atom, ?line(Meta), nil }, elixir_aliases:store(Meta, New, Old, TKV, S) }.

 no_alias_opts(KV) when is_list(KV) ->
  case lists:keyfind(as, 1, KV) of
@@ -603,41 +596,6 @@ translate_args(Args, S) ->
  { TArgs, { SC, SV } } = lists:mapfoldl(fun translate_arg/2, {S, S}, Args),
  { TArgs, umergea(SV, SC) }.

-%% Translate apply
-%% Used by both apply and external function invocation macros.
-
-translate_apply(Meta, TLeft, TRight, Args, S, SL, SR) ->
-  Line = ?line(Meta),
-
-  Optimize = case (Args == []) orelse lists:last(Args) of
-    { '|', _, _ } -> false;
-    _ ->
-      case TRight of
-        { atom, _, _ } -> true;
-        _ -> false
-      end
-  end,
-
-  case Optimize of
-    true ->
-      %% Register the remote
-      case TLeft of
-        { atom, _, Receiver } ->
-          Tuple = { element(3, TRight), length(Args) },
-          elixir_tracker:record_remote(Tuple, Receiver, S#elixir_scope.module, S#elixir_scope.function);
-        _ ->
-          ok
-      end,
-
-      { TArgs, SA } = translate_args(Args, umergec(S, SR)),
-      FS = umergev(SL, umergev(SR,SA)),
-      { { call, Line, { remote, Line, TLeft, TRight }, TArgs }, FS };
-    false ->
-      { TArgs, SA } = translate_each(Args, umergec(S, SR)),
-      FS = umergev(SL, umergev(SR,SA)),
-      { ?wrap_call(Line, erlang, apply, [TLeft, TRight, TArgs]), FS }
-  end.
-
 %% __op__ helpers

 assert_no_match_scope_for_bin_op(Meta, Op, S)
@@ -150,7 +150,8 @@ rescue_each_ref(Meta, Var, [H|T], Elixir, Erlang, _Safe, S) when
  H == 'Elixir.ArgumentError'; H == 'Elixir.ArithmeticError';
  H == 'Elixir.BadArityError'; H == 'Elixir.BadFunctionError';
  H == 'Elixir.MatchError'; H == 'Elixir.CaseClauseError';
-  H == 'Elixir.FunctionClauseError'; H == 'Elixir.SystemLimitError' ->
+  H == 'Elixir.TryClauseError'; H == 'Elixir.FunctionClauseError';
+  H == 'Elixir.SystemLimitError' ->
  Expr = { 'or', Meta, [
    erlang_rescue_guard_for(Meta, Var, H),
    exception_compare(Meta, Var, H)
@@ -176,8 +177,8 @@ rescue_each_ref(_, _, [], Elixir, Erlang, Safe, _) ->
 erlang_rescues() ->
  [
    'Elixir.UndefinedFunctionError', 'Elixir.ArgumentError', 'Elixir.ArithmeticError', 'Elixir.BadArityError',
-    'Elixir.BadFunctionError', 'Elixir.MatchError', 'Elixir.CaseClauseError', 'Elixir.FunctionClauseError',
-    'Elixir.SystemLimitError', 'Elixir.ErlangError'
+    'Elixir.BadFunctionError', 'Elixir.MatchError', 'Elixir.CaseClauseError', 'Elixir.TryClauseError',
+    'Elixir.FunctionClauseError', 'Elixir.SystemLimitError', 'Elixir.ErlangError'
  ].

 erlang_rescue_guard_for(Meta, Var, List) when is_list(List) ->
@@ -219,6 +220,12 @@ erlang_rescue_guard_for(Meta, Var, 'Elixir.CaseClauseError') ->
    exception_compare(Meta, Var, case_clause)
  ] };

+erlang_rescue_guard_for(Meta, Var, 'Elixir.TryClauseError') ->
+  { 'and', Meta, [
+    { is_tuple, Meta, [Var] },
+    exception_compare(Meta, Var, try_clause)
+  ] };
+
 erlang_rescue_guard_for(Meta, Var, 'Elixir.ArgumentError') ->
  { 'or', Meta, [
    { '==', Meta, [Var, badarg] },
@@ -1,8 +1,8 @@
 %% Convenience functions used throughout elixir source code
 %% for ast manipulation and querying.
 -module(elixir_utils).
-export([elixir_to_erl/1, elixir_to_erl/3,
-  get_line/1, split_last/1,
+-export([elixir_to_erl/1, elixir_to_erl/2,
+  get_line/1, split_last/1, elixir_to_erl/3,
  characters_to_list/1, characters_to_binary/1,
  cons_to_list/1, list_to_cons/2, list_to_cons/3,
  convert_to_boolean/5, returns_boolean/1,
@@ -10,7 +10,7 @@
 -include("elixir.hrl").
 -include_lib("kernel/include/file.hrl").

-get_line(Opts) ->
+get_line(Opts) when is_list(Opts) ->
  case lists:keyfind(line, 1, Opts) of
    { line, Line } when is_integer(Line) -> Line;
    false -> 0
@@ -5,17 +5,14 @@ defmodule KernelTest do

  doctest Access.List
  doctest String.Chars.List
-  doctest Inspect.Atom
-  doctest Inspect.BitString
-  doctest Inspect.List
-  doctest Inspect.Number
-  doctest Inspect.Regex
-  doctest Inspect.Tuple
  doctest Bitwise
  doctest Code
  doctest Enum
  doctest Exception
+  doctest Float
  doctest IO.ANSI
+  doctest Inspect.Algebra
+  doctest Integer
  doctest Keyword
  doctest Kernel
  doctest Kernel.SpecialForms
@@ -24,9 +21,11 @@ defmodule KernelTest do
  doctest Module
  doctest OptionParser
  doctest Path
+  doctest Protocol.Consolidation
  doctest Regex
  doctest Set
  doctest Stream
  doctest String
-  doctest Inspect.Algebra
+  doctest Tuple
+  doctest Version
 end
@@ -5,6 +5,11 @@ defmodule CodeTest do
  import PathHelpers

  def one, do: 1
+  def genmodule(name) do
+    defmodule name do
+      Kernel.LexicalTracker.remotes(__MODULE__)
+    end
+  end

  contents = quote do
    defmodule CodeTest.Sample do
@@ -19,6 +24,10 @@ defmodule CodeTest do
    assert { 3, _ } = Code.eval_string("a + b", [a: 1, b: 2], __ENV__.location)
  end

+  test :eval_string_with_other_context do
+    assert Code.eval_string("var!(a, Sample) = 1") == { 1, [{{:a,Sample},1}] }
+  end
+
  test :eval_with_unnamed_scopes do
    assert { RuntimeError[], [a: RuntimeError[]] } =
           Code.eval_string("a = (try do (raise \"hello\") rescue e -> e end)")
@@ -60,15 +69,6 @@ defmodule CodeTest do
    assert Code.require_file(fixture_path("code_sample.exs")) != nil
  end

-  test :path_manipulation do
-    path = __DIR__
-    Code.prepend_path path
-    assert to_char_list(path) in :code.get_path
-
-    Code.delete_path path
-    refute to_char_list(path) in :code.get_path
-  end
-
  test :file do
    assert :filename.absname(__FILE__) == __FILE__
  end
@@ -104,6 +104,13 @@ defmodule CodeTest do
    assert Keyword.get(compile, :source) != nil
  end

+  test :compile_string_works_accross_lexical_scopes do
+    assert [{ CompileCrossSample, _ }] = Code.compile_string("CodeTest.genmodule CompileCrossSample")
+  after
+    :code.purge CompileCrossSample
+    :code.delete CompileCrossSample
+  end
+
  test :compile_string do
    assert [{ CompileStringSample, _ }] = Code.compile_string("defmodule CompileStringSample, do: :ok")
  after
@@ -128,3 +135,16 @@ defmodule CodeTest do
    refute Code.ensure_compiled?(Unknown.Module)
  end
 end
+
+defmodule Code.SyncTest do
+  use ExUnit.Case
+
+  test :path_manipulation do
+    path = Path.join(__DIR__, "fixtures")
+    Code.prepend_path path
+    assert to_char_list(path) in :code.get_path
+
+    Code.delete_path path
+    refute to_char_list(path) in :code.get_path
+  end
+end
@@ -3,8 +3,8 @@ Code.require_file "test_helper.exs", __DIR__
 defmodule DictTest.Common do
  defmacro __using__(module) do
    quote location: :keep do
-      # Most underlying Dict implementations have no key order guarantees,
-      # sort them before we compare:
+      # Most underlying Dict implementations have no key
+      # order guarantees, sort them before we compare:
      defmacrop dicts_equal(actual, expected) do
        quote do
          cmp = fn { k1, _ }, { k2, _ } -> k1 < k2 end
@@ -12,12 +12,31 @@ defmodule DictTest.Common do
        end
      end

+      defp empty_dict, do: unquote(module).new
+
+      defp new_dict(list // [{"first_key", 1}, {"second_key", 2}]) do
+        unquote(module).new list
+      end
+
+      defp new_dict(list, transform) do
+        unquote(module).new list, transform
+      end
+
+      defp int_dict do
+        unquote(module).new [{1,1}]
+      end
+
      test :access do
        dict = new_dict [{"first_key", 1}, {"second_key", 2}]
        assert dict["first_key"] == 1
        assert dict["third_key"] == nil
      end

+      test :access_with_match do
+        assert int_dict[1] == 1
+        assert int_dict[1.0] == nil
+      end
+
      test :new_pairs do
        dict = new_dict [{"first_key", 1}, {"second_key", 2}]
        assert 2 == Dict.size dict
@@ -41,12 +60,22 @@ defmodule DictTest.Common do
        assert "default" == Dict.get(empty_dict, "first_key", "default")
      end

+      test :get_with_match do
+        assert Dict.get(int_dict, 1) == 1
+        assert Dict.get(int_dict, 1.0) == nil
+      end
+
      test :fetch do
        assert { :ok, 1 } == Dict.fetch(new_dict, "first_key")
        assert { :ok, 2 } == Dict.fetch(new_dict, "second_key")
        assert :error     == Dict.fetch(new_dict, "other_key")
      end

+      test :fetch_with_match do
+        assert Dict.fetch(int_dict, 1) == { :ok, 1 }
+        assert Dict.fetch(int_dict, 1.0) == :error
+      end
+
      test :fetch! do
        assert 1 == Dict.fetch!(new_dict, "first_key")
        assert 2 == Dict.fetch!(new_dict, "second_key")
@@ -55,36 +84,62 @@ defmodule DictTest.Common do
        end
      end

+      test :fetch_with_match! do
+        assert Dict.fetch!(int_dict, 1) == 1
+        assert_raise KeyError, fn ->
+          assert Dict.fetch!(int_dict, 1.0)
+        end
+      end
+
      test :put do
        dict = Dict.put(new_dict, "first_key", {1})
        assert {1} == Dict.get dict, "first_key"
        assert 2 == Dict.get dict, "second_key"
      end

+      test :put_with_match do
+        assert Dict.get(Dict.put(int_dict, 1, :other), 1)     == :other
+        assert Dict.get(Dict.put(int_dict, 1.0, :other), 1)   == 1
+        assert Dict.get(Dict.put(int_dict, 1, :other), 1.0)   == nil
+        assert Dict.get(Dict.put(int_dict, 1.0, :other), 1.0) == :other
+      end
+
      test :put_new do
        dict = Dict.put_new(new_dict, "first_key", {1})
        assert 1 == Dict.get dict, "first_key"
      end

+      test :put_new_with_match do
+        assert Dict.get(Dict.put_new(int_dict, 1, :other), 1)     == 1
+        assert Dict.get(Dict.put_new(int_dict, 1.0, :other), 1)   == 1
+        assert Dict.get(Dict.put_new(int_dict, 1, :other), 1.0)   == nil
+        assert Dict.get(Dict.put_new(int_dict, 1.0, :other), 1.0) == :other
+      end
+
      test :keys do
-        assert ["first_key", "second_key"] == Enum.sort Dict.keys new_dict
-        assert [] == Dict.keys empty_dict
+        assert Enum.sort(Dict.keys new_dict) == ["first_key", "second_key"]
+        assert Dict.keys(empty_dict) == []
      end

      test :values do
-        assert [1, 2] ==Enum.sort Dict.values(new_dict)
-        assert [] == Dict.values empty_dict
+        assert Enum.sort(Dict.values(new_dict)) == [1, 2]
+        assert Dict.values(empty_dict) == []
      end

      test :delete do
        mdict = Dict.delete new_dict, "second_key"
-        assert 1 == Dict.size mdict
+        assert Dict.size(mdict) == 1
        assert Dict.has_key? mdict, "first_key"
        refute Dict.has_key? mdict, "second_key"

        mdict = Dict.delete(new_dict, "other_key")
        assert mdict == new_dict
-        assert 0 == Dict.size Dict.delete(empty_dict, "other_key")
+        assert Dict.size(Dict.delete(empty_dict, "other_key")) == 0
+      end
+
+      test :delete_with_match do
+        assert Dict.get(Dict.delete(int_dict, 1), 1) == nil
+        assert Dict.get(Dict.delete(int_dict, 1.0), 1) == 1
      end

      test :merge do
@@ -123,17 +178,28 @@ defmodule DictTest.Common do
        refute Dict.has_key?(dict, "b")
      end

+      test :has_key_with_match do
+        assert Dict.has_key?(int_dict, 1)
+        refute Dict.has_key?(int_dict, 1.0)
+      end
+
      test :size do
        assert 2 == Dict.size new_dict
        assert 0 == Dict.size empty_dict
      end

      test :update do
-        dict = Dict.update! new_dict, "first_key", fn val -> -val end
-        assert -1 == Dict.get dict, "first_key"
+        dict = Dict.update!(new_dict, "first_key", fn val -> -val end)
+        assert Dict.get(dict, "first_key") == -1

-        dict = Dict.update dict, "non-existent", "...", fn val -> -val end
-        assert "..." == Dict.get dict, "non-existent"
+        dict = Dict.update(dict, "non-existent", "...", fn val -> -val end)
+        assert Dict.get(dict, "non-existent") == "..."
+      end
+
+      test :update_with_match do
+        assert Dict.get(Dict.update!(int_dict, 1, &(&1 + 1)), 1) == 2
+        assert Dict.get(Dict.update(int_dict, 1.0, 2, &(&1 + 1)), 1) == 1
+        assert Dict.get(Dict.update(int_dict, 1.0, 2, &(&1 + 1)), 1.0) == 2
      end

      test :pop do
@@ -158,6 +224,16 @@ defmodule DictTest.Common do
        assert dicts_equal actual, new_dict
      end

+      test :pop_with_match do
+        {v, actual} = Dict.pop(int_dict, 1)
+        assert v == 1
+        assert dicts_equal actual, []
+
+        {v, actual} = Dict.pop(int_dict, 1.0)
+        assert v == nil
+        assert dicts_equal actual, int_dict
+      end
+
      test :split do
        split_keys = []
        {take, drop} = Dict.split(new_dict, split_keys)
@@ -185,6 +261,16 @@ defmodule DictTest.Common do
        assert dicts_equal drop, drop_expected
      end

+      test :split_with_match do
+        { take, drop } = Dict.split(int_dict, [1])
+        assert dicts_equal take, int_dict
+        assert dicts_equal drop, []
+
+        { take, drop } = Dict.split(int_dict, [1.0])
+        assert dicts_equal take, []
+        assert dicts_equal drop, int_dict
+      end
+
      test :take do
        result = Dict.take(new_dict, ["unknown_key"])
        assert dicts_equal result, Dict.empty(new_dict)
@@ -195,6 +281,11 @@ defmodule DictTest.Common do
        assert dicts_equal result, expected
      end

+      test :take_with_match do
+        assert dicts_equal Dict.take(int_dict, [1]), int_dict
+        assert dicts_equal Dict.take(int_dict, [1.0]), []
+      end
+
      test :drop do
        result = Dict.drop(new_dict, ["unknown_key"])
        assert dicts_equal result, new_dict
@@ -203,17 +294,44 @@ defmodule DictTest.Common do
        assert dicts_equal result, Dict.delete(new_dict, "first_key")
      end

+      test :drop_with_match do
+        assert dicts_equal Dict.drop(int_dict, [1]), []
+        assert dicts_equal Dict.drop(int_dict, [1.0]), int_dict
+      end
+
      test :empty do
        assert empty_dict == Dict.empty new_dict
      end

      test :equal? do
-        dict1 = HashDict.new(a: 2, b: 3, f: 5, c: 123)
-        dict2 = ListDict.new(a: 2, b: 3, f: 5, c: 123)
+        dict1 = new_dict(a: 2, b: 3, f: 5, c: 123)
+        dict2 = new_dict(a: 2, b: 3, f: 5, c: 123)
+        assert dict_impl.equal?(dict1, dict2)
        assert Dict.equal?(dict1, dict2)

        dict2 = Dict.put(dict2, :a, 3)
+        refute dict_impl.equal?(dict1, dict2)
        refute Dict.equal?(dict1, dict2)
+
+        dict3 = [a: 2, b: 3, f: 5, c: 123, z: 666]
+        refute Dict.equal?(dict1, dict3)
+        refute Dict.equal?(dict3, dict1)
+      end
+
+      test :equal_with_match? do
+        dict1 = new_dict([{1,1}])
+        dict2 = new_dict([{1.0,1}])
+        assert dict_impl.equal?(dict1, dict1)
+        refute dict_impl.equal?(dict1, dict2)
+        assert Dict.equal?(dict1, dict1)
+        refute Dict.equal?(dict1, dict2)
+      end
+
+      test :enum_member do
+        assert Enum.member?(new_dict([{1,1}]), { 1, 1 })
+        refute Enum.member?(new_dict([{1,1}]), { 1.0, 1 })
+        refute Enum.member?(new_dict([{1,1}]), { 1, 1.0 })
+        refute Enum.member?(new_dict([{1,1}]), { 1.0, 1.0 })
      end

      test "unsupported dict" do
@@ -221,16 +339,6 @@ defmodule DictTest.Common do
          Dict.to_list :bad_dict
        end
      end
-
-      defp empty_dict, do: unquote(module).new
-
-      defp new_dict(list // [{"first_key", 1}, {"second_key", 2}]) do
-        unquote(module).new list
-      end
-
-      defp new_dict(list, transform) do
-        unquote(module).new list, transform
-      end
    end
  end
 end
@@ -152,14 +152,14 @@ defmodule EnumTest.List do
  end

  test :filter_with_match do
-    assert Enum.filter([1, 2, 3], match?(1, &1)) == [1]
-    assert Enum.filter([1, 2, 3], match?(x when x < 3, &1)) == [1, 2]
-    assert Enum.filter([1, 2, 3], match?(_, &1)) == [1, 2, 3]
+    assert Enum.filter([1, 2, 3], &match?(1, &1)) == [1]
+    assert Enum.filter([1, 2, 3], &match?(x when x < 3, &1)) == [1, 2]
+    assert Enum.filter([1, 2, 3], &match?(_, &1)) == [1, 2, 3]
  end

  test :filter_map do
-    assert Enum.filter_map([1, 2, 3], fn(x) -> rem(x, 2) == 0 end, &1 * 2) == [4]
-    assert Enum.filter_map([2, 4, 6], fn(x) -> rem(x, 2) == 0 end, &1 * 2) == [4, 8, 12]
+    assert Enum.filter_map([1, 2, 3], fn(x) -> rem(x, 2) == 0 end, &(&1 * 2)) == [4]
+    assert Enum.filter_map([2, 4, 6], fn(x) -> rem(x, 2) == 0 end, &(&1 * 2)) == [4, 8, 12]
  end

  test :flat_map do
@@ -185,15 +185,15 @@ defmodule EnumTest.List do
  end

  test :map_join do
-    assert Enum.map_join([], " = ", &1 * 2) == ""
-    assert Enum.map_join([1, 2, 3], " = ", &1 * 2) == "2 = 4 = 6"
-    assert Enum.map_join([1, 2, 3], &1 * 2) == "246"
+    assert Enum.map_join([], " = ", &(&1 * 2)) == ""
+    assert Enum.map_join([1, 2, 3], " = ", &(&1 * 2)) == "2 = 4 = 6"
+    assert Enum.map_join([1, 2, 3], &(&1 * 2)) == "246"
  end

  test :join_empty do
    fun = fn (acc, _) -> acc end
    assert Enum.join(fun, ".") == ""
-    assert Enum.map_join(fun, ".", &1 + 0) == ""
+    assert Enum.map_join(fun, ".", &(&1 + 0)) == ""
  end

  test :map do
@@ -229,7 +229,7 @@ defmodule EnumTest.List do

  test :sort do
    assert Enum.sort([5, 3, 2, 4, 1]) == [1, 2, 3, 4, 5]
-    assert Enum.sort([5, 3, 2, 4, 1], &1 > &2) == [5, 4, 3, 2, 1]
+    assert Enum.sort([5, 3, 2, 4, 1], &(&1 > &2)) == [5, 4, 3, 2, 1]
  end

  test :split do
@@ -264,6 +264,13 @@ defmodule EnumTest.List do
    assert Enum.take([], 3) == []
  end

+  test :take_every do
+    assert Enum.take_every([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 2) == [1, 3, 5, 7, 9]
+    assert Enum.take_every([], 2) == []
+    assert Enum.take_every([1, 2], 2) == [1]
+    assert Enum.take_every([1, 2, 3], 0) == []
+  end
+
  test :take_while do
    assert Enum.take_while([1, 2, 3], fn(x) -> x > 3 end) == []
    assert Enum.take_while([1, 2, 3], fn(x) -> x <= 1 end) == [1]
@@ -358,6 +365,25 @@ defmodule EnumTest.List do
    assert Enum.slice([1,2,3,4,5], -2, 5) == [4, 5]
    assert Enum.slice([1,2,3,4,5], -3, 1) == [3]
  end
+
+  test :slice_range do
+    assert Enum.slice([1,2,3,4,5], 0..0) == [1]
+    assert Enum.slice([1,2,3,4,5], 0..1) == [1, 2]
+    assert Enum.slice([1,2,3,4,5], 0..2) == [1, 2, 3]
+    assert Enum.slice([1,2,3,4,5], 1..2) == [2, 3]
+    assert Enum.slice([1,2,3,4,5], 1..0) == nil 
+    assert Enum.slice([1,2,3,4,5], 2..5) == [3, 4, 5]
+    assert Enum.slice([1,2,3,4,5], 4..4) == [5]
+    assert Enum.slice([1,2,3,4,5], 5..5) == []
+    assert Enum.slice([1,2,3,4,5], 6..5) == nil 
+    assert Enum.slice([1,2,3,4,5], 6..0) == nil 
+    assert Enum.slice([1,2,3,4,5], -6..0) == nil 
+    assert Enum.slice([1,2,3,4,5], -6..5) == nil 
+    assert Enum.slice([1,2,3,4,5], -5..-1) == [1, 2, 3, 4, 5]
+    assert Enum.slice([1,2,3,4,5], -5..-3) == [1, 2, 3]
+    assert Enum.slice([1,2,3,4,5], -6..-1) == nil
+    assert Enum.slice([1,2,3,4,5], -6..-3) == nil
+  end
 end

 defmodule EnumTest.Range do
@@ -377,10 +403,10 @@ defmodule EnumTest.Range do

  test :any? do
    range = Range.new(first: 0, last: 5)
-    refute Enum.any?(range, &1 > 10)
+    refute Enum.any?(range, &(&1 > 10))

    range = Range.new(first: 0, last: 5)
-    assert Enum.any?(range, &1 > 3)
+    assert Enum.any?(range, &(&1 > 3))

    range = Range.new(first: 1, last: 0)
    assert Enum.any?(range)
@@ -510,17 +536,17 @@ defmodule EnumTest.Range do

  test :filter_with_match do
    range = Range.new(first: 1, last: 3)
-    assert Enum.filter(range, match?(1, &1)) == [1]
-    assert Enum.filter(range, match?(x when x < 3, &1)) == [1, 2]
-    assert Enum.filter(range, match?(_, &1)) == [1, 2, 3]
+    assert Enum.filter(range, &match?(1, &1)) == [1]
+    assert Enum.filter(range, &match?(x when x < 3, &1)) == [1, 2]
+    assert Enum.filter(range, &match?(_, &1)) == [1, 2, 3]
  end

  test :filter_map do
    range = Range.new(first: 1, last: 3)
-    assert Enum.filter_map(range, fn(x) -> rem(x, 2) == 0 end, &1 * 2) == [4]
+    assert Enum.filter_map(range, fn(x) -> rem(x, 2) == 0 end, &(&1 * 2)) == [4]

    range = Range.new(first: 2, last: 6)
-    assert Enum.filter_map(range, fn(x) -> rem(x, 2) == 0 end, &1 * 2) == [4, 8, 12]
+    assert Enum.filter_map(range, fn(x) -> rem(x, 2) == 0 end, &(&1 * 2)) == [4, 8, 12]
  end

  test :flat_map do
@@ -558,11 +584,11 @@ defmodule EnumTest.Range do

  test :map_join do
    range = Range.new(first: 1, last: 0)
-    assert Enum.map_join(range, " = ", &1 * 2) == "2 = 0"
+    assert Enum.map_join(range, " = ", &(&1 * 2)) == "2 = 0"

    range = Range.new(first: 1, last: 3)
-    assert Enum.map_join(range, " = ", &1 * 2) == "2 = 4 = 6"
-    assert Enum.map_join(range, &1 * 2) == "246"
+    assert Enum.map_join(range, " = ", &(&1 * 2)) == "2 = 4 = 6"
+    assert Enum.map_join(range, &(&1 * 2)) == "246"
  end

  test :map do
@@ -597,9 +623,9 @@ defmodule EnumTest.Range do
    assert Enum.sort(Range.new(first: 2, last: 1)) == [1, 2]
    assert Enum.sort(Range.new(first: 1, last: 1)) == [1]

-    assert Enum.sort(Range.new(first: 3, last: 1), &1 > &2) == [3, 2, 1]
-    assert Enum.sort(Range.new(first: 2, last: 1), &1 > &2) == [2, 1]
-    assert Enum.sort(Range.new(first: 1, last: 1), &1 > &2) == [1]
+    assert Enum.sort(Range.new(first: 3, last: 1), &(&1 > &2)) == [3, 2, 1]
+    assert Enum.sort(Range.new(first: 2, last: 1), &(&1 > &2)) == [2, 1]
+    assert Enum.sort(Range.new(first: 1, last: 1), &(&1 > &2)) == [1]
  end

  test :split do
@@ -642,6 +668,12 @@ defmodule EnumTest.Range do
    assert Enum.take(range, 3) == [1, 0]
  end

+  test :take_every do
+    assert Enum.take_every(1..10, 2) == [1, 3, 5, 7, 9]
+    assert Enum.take_every(1..2, 2) == [1]
+    assert Enum.take_every(1..3, 0) == []
+  end
+
  test :take_while do
    range = Range.new(first: 1, last: 3)
    assert Enum.take_while(range, fn(x) -> x > 3 end) == []
@@ -724,6 +756,25 @@ defmodule EnumTest.Range do
    assert Enum.slice(1..5, -2, 5) == [4, 5]
    assert Enum.slice(1..5, -3, 1) == [3]
  end
+  
+  test :slice_range do
+    assert Enum.slice(1..5, 0..0) == [1]
+    assert Enum.slice(1..5, 0..1) == [1, 2]
+    assert Enum.slice(1..5, 0..2) == [1, 2, 3]
+    assert Enum.slice(1..5, 1..2) == [2, 3]
+    assert Enum.slice(1..5, 1..0) == nil 
+    assert Enum.slice(1..5, 2..5) == [3, 4, 5]
+    assert Enum.slice(1..5, 4..4) == [5]
+    assert Enum.slice(1..5, 5..5) == []
+    assert Enum.slice(1..5, 6..5) == nil 
+    assert Enum.slice(1..5, 6..0) == nil 
+    assert Enum.slice(1..5, -6..0) == nil 
+    assert Enum.slice(1..5, -6..5) == nil 
+    assert Enum.slice(1..5, -5..-1) == [1, 2, 3, 4, 5]
+    assert Enum.slice(1..5, -5..-3) == [1, 2, 3]
+    assert Enum.slice(1..5, -6..-1) == nil
+    assert Enum.slice(1..5, -6..-3) == nil
+  end
 end

 defmodule EnumTest.Others do
@@ -3,6 +3,9 @@ Code.require_file "test_helper.exs", __DIR__
 defmodule Kernel.ExceptionTest do
  use ExUnit.Case, async: true

+  # Ensure fields passed through an expression are valid
+  defexception Custom, %w(message)a
+
  test :is_exception do
    assert is_exception(RuntimeError.new)
    refute is_exception(empty_tuple)
@@ -51,6 +54,7 @@ defmodule Kernel.ExceptionTest do
    assert Exception.format_mfa(Foo, nil, 1) == "Foo.nil/1"
    assert Exception.format_mfa(Foo, :bar, 1) == "Foo.bar/1"
    assert Exception.format_mfa(Foo, :bar, []) == "Foo.bar()"
+    assert Exception.format_mfa(nil, :bar, []) == "nil.bar()"
    assert Exception.format_mfa(:foo, :bar, [1, 2]) == ":foo.bar(1, 2)"
    assert Exception.format_mfa(Foo, :"bar baz", 1) == "Foo.\"bar baz\"/1"
  end
@@ -73,6 +77,7 @@ defmodule Kernel.ExceptionTest do
  test :undefined_function_message do
    assert UndefinedFunctionError.new.message == "undefined function"
    assert UndefinedFunctionError.new(module: Foo, function: :bar, arity: 1).message == "undefined function: Foo.bar/1"
+    assert UndefinedFunctionError.new(module: nil, function: :bar, arity: 0).message == "undefined function: nil.bar/0"
  end

  test :function_clause_message do
@@ -84,6 +89,26 @@ defmodule Kernel.ExceptionTest do
    assert ErlangError.new(original: :sample).message == "erlang error: :sample"
  end

+  test :raise_preserves_the_stacktrace do
+    stacktrace =
+    try do
+      raise "a"
+    rescue _ ->
+      [top|_] = System.stacktrace
+      top
+    end
+    file = to_char_list(__FILE__)
+    assert {Kernel.ExceptionTest, :test_raise_preserves_the_stacktrace, _,
+           [file: ^file, line: 95]} = stacktrace # line is sensitive
+  end
+
+  test :defexception do
+    defexception SampleError, field: :ok do
+      # Check do block is properly inline
+      def message(_), do: "hello"
+    end
+  end
+
  defp empty_tuple, do: {}
  defp a_tuple, do: { :foo, :bar, :baz }
  defp a_list,  do: [ :foo, :bar, :baz ]
@@ -550,7 +550,7 @@ defmodule FileTest do

    test :open_a_file_with_function do
      file = fixture_path("file.txt")
-      assert File.open(file, IO.read(&1, :line)) == { :ok, "FOO\n" }
+      assert File.open(file, &IO.read(&1, :line)) == { :ok, "FOO\n" }
    end

    test :open_a_missing_file! do
@@ -562,7 +562,7 @@ defmodule FileTest do

    test :open_a_file_with_function! do
      file = fixture_path("file.txt")
-      assert File.open!(file, IO.read(&1, :line)) == "FOO\n"
+      assert File.open!(file, &IO.read(&1, :line)) == "FOO\n"
    end
  end

@@ -0,0 +1,28 @@
+Code.require_file "test_helper.exs", __DIR__
+
+defmodule FloatTest do
+  use ExUnit.Case, async: true
+
+  test :parse do
+    assert Float.parse("12") === {12.0, ""}
+    assert Float.parse("-12") === {-12.0, ""}
+    assert Float.parse("123456789") === {123456789.0, ""}
+    assert Float.parse("12.5") === {12.5, ""}
+    assert Float.parse("12.524235") === {12.524235, ""}
+    assert Float.parse("-12.5") === {-12.5, ""}
+    assert Float.parse("-12.524235") === {-12.524235, ""}
+    assert Float.parse("7.5e3") === {7.5e3, ""}
+    assert Float.parse("7.5e-3") === {7.5e-3, ""}
+    assert Float.parse("12x") === {12.0, "x"}
+    assert Float.parse("12.5x") === {12.5, "x"}
+    assert Float.parse("-12.32453e10") === {-1.232453e11, ""}
+    assert Float.parse("-12.32453e-10") === {-1.232453e-9, ""}
+    assert Float.parse("0.32453e-10") === {3.2453e-11, ""}
+    assert Float.parse("1.32453e-10") === {1.32453e-10, ""}
+    assert Float.parse("1.32.45") === {1.32, ".45"}
+    assert Float.parse("1.o") === {1.0, ".o"}
+    assert Float.parse("--1.2") === :error
+    assert Float.parse("++1.2") === :error
+    assert Float.parse("pi") === :error
+  end
+end
@@ -85,31 +85,31 @@ defmodule HashDictTest do
  test :update do
    dict = filled_dict(8)

-    dict = HashDict.update!(dict, 1, &1 * 2)
+    dict = HashDict.update!(dict, 1, &(&1 * 2))
    assert HashDict.get(dict, 1) == 2
    assert HashDict.size(dict) == 8

    assert_raise KeyError, fn ->
-      HashDict.update!(dict, 11, &1 * 2)
+      HashDict.update!(dict, 11, &(&1 * 2))
    end

-    dict = HashDict.update(dict, 3, 3, &1 * 2)
+    dict = HashDict.update(dict, 3, 3, &(&1 * 2))
    assert HashDict.get(dict, 3) == 6
    assert HashDict.size(dict) == 8

-    dict = HashDict.update(dict, 11, 13, &1 * 2)
+    dict = HashDict.update(dict, 11, 13, &(&1 * 2))
    assert HashDict.get(dict, 11) == 13
    assert HashDict.size(dict) == 9

    assert_raise KeyError, fn->
-      HashDict.update!(dict, 11.0, &1 * 2)
+      HashDict.update!(dict, 11.0, &(&1 * 2))
    end

-    dict = HashDict.update(dict, 11.0, 15, &1 * 2)
+    dict = HashDict.update(dict, 11.0, 15, &(&1 * 2))
    assert HashDict.get(dict, 11.0) == 15
    assert HashDict.size(dict) == 10

-    dict = HashDict.update(dict, 11.0, 15, &1 * 2)
+    dict = HashDict.update(dict, 11.0, 15, &(&1 * 2))
    assert HashDict.get(dict, 11.0) == 30
    assert HashDict.get(dict, 11) == 13
    assert HashDict.size(dict) == 10
@@ -302,6 +302,6 @@ defmodule HashDictTest do
  end

  defp filled_dict(range) do
-    Enum.reduce 1..range, HashDict.new, HashDict.put(&2, &1, &1)
+    Enum.reduce 1..range, HashDict.new, &HashDict.put(&2, &1, &1)
  end
 end
@@ -40,10 +40,8 @@ defmodule HashSetTest do
    diff = HashSet.difference(filled_set(9000), filled_set(9000))
    assert HashSet.equal?(diff, HashSet.new([]))

-    #Ensure the trie has correctly resized
-    assert HashSet.inspect_depth(diff) == 0
-    assert HashSet.inspect_contract(diff) ==  2
-    assert HashSet.inspect_expand(diff) == 80
+    # Ensure the trie has correctly resized
+    assert { HashSet, 0, 0, 80, 2, _ } = diff
  end

  test "member? with ordered sets"  do
@@ -110,7 +108,7 @@ defmodule HashSetTest do
  end

  defp filled_set(range) do
-    Enum.reduce 1..range, HashSet.new, HashSet.put(&2, &1)
+    Enum.reduce 1..range, HashSet.new, &HashSet.put(&2, &1)
  end
 end

@@ -65,8 +65,6 @@ defmodule Inspect.BitStringTest do
    assert inspect("f\no") == "\"f\\no\""
    assert inspect("f\\o") == "\"f\\\\o\""
    assert inspect("f\ao") == "\"f\\ao\""
-    assert inspect(%S{#{#a}) == "\"\\\#{#a\""
-    assert inspect(%S{ #{#a}) == "\" \\\#{#a\""
  end

  test :utf8 do
@@ -20,4 +20,17 @@ defmodule IntegerTest do
    assert Integer.even?(-2) == true
    assert Integer.even?(-3) == false
  end
+
+  test :parse do
+    assert Integer.parse("12") === {12, ""}
+    assert Integer.parse("-12") === {-12, ""}
+    assert Integer.parse("123456789") === {123456789, ""}
+    assert Integer.parse("12.5") === {12, ".5"}
+    assert Integer.parse("7.5e-3") === {7, ".5e-3"}
+    assert Integer.parse("12x") === {12, "x"}
+    assert Integer.parse("++1") === :error
+    assert Integer.parse("--1") === :error
+    assert Integer.parse("+-1") === :error
+    assert Integer.parse("three") === :error
+  end
 end
@@ -2,6 +2,7 @@ Code.require_file "test_helper.exs", __DIR__

 defmodule IOTest do
  use ExUnit.Case, async: true
+  import ExUnit.CaptureIO

  test :read_with_count do
    { :ok, file } = File.open(Path.expand('../fixtures/file.txt', __FILE__), [:charlist])
@@ -77,4 +78,32 @@ defmodule IOTest do
    assert "日\n" == IO.binread(file, :line)
    assert File.close(file) == :ok
  end
+
+  test :puts_with_chardata do
+    assert capture_io(fn -> IO.puts("hello") end) == "hello\n"
+    assert capture_io(fn -> IO.puts('hello') end) == "hello\n"
+    assert capture_io(fn -> IO.puts(:hello) end) == "hello\n"
+    assert capture_io(fn -> IO.puts(13) end) == "13\n"
+  end
+
+  test :write_with_chardata do
+    assert capture_io(fn -> IO.write("hello") end) == "hello"
+    assert capture_io(fn -> IO.write('hello') end) == "hello"
+    assert capture_io(fn -> IO.write(:hello) end) == "hello"
+    assert capture_io(fn -> IO.write(13) end) == "13"
+  end
+
+  test :gets_with_chardata do
+    assert capture_io("foo\n", fn -> IO.gets("hello") end) == "hello"
+    assert capture_io("foo\n", fn -> IO.gets('hello') end) == "hello"
+    assert capture_io("foo\n", fn -> IO.gets(:hello) end) == "hello"
+    assert capture_io("foo\n", fn -> IO.gets(13) end) == "13"
+  end
+
+  test :getn_with_chardata do
+    assert capture_io("foo\n", fn -> IO.getn("hello", 3) end) == "hello"
+    assert capture_io("foo\n", fn -> IO.getn('hello', 3) end) == "hello"
+    assert capture_io("foo\n", fn -> IO.getn(:hello, 3) end) == "hello"
+    assert capture_io("foo\n", fn -> IO.getn(13, 3) end) == "13"
+  end
 end
@@ -29,9 +29,9 @@ defmodule Kernel.AliasTest do

  test :lexical do
    if true do
-      alias OMG, as: List
+      alias OMG, as: List, warn: false
    else
-      alias ABC, as: List
+      alias ABC, as: List, warn: false
    end

    assert List.flatten([1, [2], 3]) == [1, 2, 3]
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .10.2
 .11.2