Release v1.4.3

Signed-off-by: José Valim <jose.valim@plataformatec.com.br>

.cirrus.yml

@@ -1,50 +0,0 @@
-env:
-  CIRRUS_CLONE_DEPTH: 50
-  ELIXIR_ASSERT_TIMEOUT: 2000
-  ELIXIRC_OPTS: "--warnings-as-errors"
-  ERLC_OPTS: "warnings_as_errors"
-  LANG: C.UTF-8
-
-test_template: &DEFAULT_TEST_SETTINGS
-  # don't cancel the task execution if it's master or a release branch
-  auto_cancellation: $CIRRUS_BRANCH != 'master' && $CIRRUS_BRANCH !=~ 'v\d+\.\d+.*'
-
-test_freebsd_task:
-  <<: *DEFAULT_TEST_SETTINGS
-
-  name: FreeBSD 13.0
-  alias: FreeBSD Stable
-
-  freebsd_instance:
-    image_family: freebsd-13-0
-    cpu: 8
-    memory: 7424Mi
-
-  env:
-    CHECK_REPRODUCIBLE: true
-    LC_ALL: en_US.UTF-8
-    PATH: $PATH:/usr/local/lib/erlang22/bin
-
-  install_script:
-    - pkg install -y erlang-runtime22 git gmake
-    - rm -rf .git
-    - gmake compile
-
-  build_info_script: bin/elixir --version
-
-  test_formatted_script:
-    - gmake test_formatted &&
-      echo "All Elixir source code files are properly formatted."
-
-  dialyzer_script: dialyzer -pa lib/elixir/ebin --build_plt --output_plt elixir.plt --apps lib/elixir/ebin/elixir.beam lib/elixir/ebin/Elixir.Kernel.beam
-
-  test_erlang_script: gmake test_erlang
-
-  test_elixir_script: gmake test_elixir
-
-  check_reproducible_script: |
-    if [ -n "$CHECK_REPRODUCIBLE" ]; then
-      gmake check_reproducible
-    else
-      echo "The reproducibility of the build is only checked in the last stable Erlang/OTP version."
-    fi

.formatter.exs

@@ -1,18 +0,0 @@
-[
-  inputs: [
-    "lib/*/{lib,unicode,test}/**/*.{ex,exs}",
-    "lib/*/*.exs",
-    "lib/ex_unit/examples/*.exs",
-    ".formatter.exs"
-  ],
-  locals_without_parens: [
-    # Formatter tests
-    assert_format: 2,
-    assert_format: 3,
-    assert_same: 1,
-    assert_same: 2,
-
-    # Errors tests
-    assert_eval_raise: 3
-  ]
-]

.gitattributes

@@ -1,3 +1 @@
 lib/elixir/test/elixir/fixtures/*.txt text eol=lf
-*.ex diff=elixir
-*.exs diff=elixir

.github/ISSUE_TEMPLATE.md

@@ -1,21 +0,0 @@
-### Precheck
-
-* For proposing a new feature, please start a discussion on the Elixir Core mailing list: https://groups.google.com/group/elixir-lang-core
-* For bugs, do a quick search and make sure the bug has not yet been reported
-* Please disclose security vulnerabilities privately at elixir-security@googlegroups.com
-* Do not use the issues tracker for guidance, questions or support (try Elixir Forum, Stack Overflow, Slack, etc. instead)
-* Finally, be nice and have fun!
-
-### Environment
-
-* Elixir & Erlang/OTP versions (elixir --version): 
-* Operating system: 
-
-### Current behavior
-
-Include code samples, errors and stacktraces if appropriate.
-If reporting a bug, please include the reproducing steps.
-
-### Expected behavior
-
-A short description on how you expect the code to behave.

.github/workflows/ci.yml

@@ -1,106 +0,0 @@
-name: CI
-
-on: [pull_request, push]
-
-env:
-  ELIXIR_ASSERT_TIMEOUT: 2000
-  ELIXIRC_OPTS: "--warnings-as-errors"
-  ERLC_OPTS: "warnings_as_errors"
-  LANG: C.UTF-8
-
-jobs:
-  test_linux:
-    name: Linux, ${{ matrix.otp_release }}, Ubuntu 18.04
-    strategy:
-      fail-fast: false
-      matrix:
-        otp_release: ['OTP-24.0', 'OTP-23.3', 'OTP-23.0', 'OTP-22.3', 'OTP-22.0']
-        development: [false]
-        include:
-          - otp_release: master
-            development: true
-          - otp_release: maint
-            development: true
-    runs-on: ubuntu-18.04
-    steps:
-      - uses: actions/checkout@v2
-        with:
-          fetch-depth: 50
-      - name: Install Erlang/OTP
-        run: |
-          cd $RUNNER_TEMP
-          wget -O otp.tar.gz https://repo.hex.pm/builds/otp/ubuntu-18.04/${{ matrix.otp_release }}.tar.gz
-          mkdir -p otp
-          tar zxf otp.tar.gz -C otp --strip-components=1
-          otp/Install -minimal $(pwd)/otp
-          echo "$(pwd)/otp/bin" >> $GITHUB_PATH
-      - name: Compile Elixir
-        run: |
-          rm -rf .git
-          make compile
-      - name: Build info
-        run: bin/elixir --version
-      - name: Check format
-        run: make test_formatted && echo "All Elixir source code files are properly formatted."
-      - name: Dyalizer
-        run: dialyzer -pa lib/elixir/ebin --build_plt --output_plt elixir.plt --apps lib/elixir/ebin/elixir.beam lib/elixir/ebin/Elixir.Kernel.beam
-      - name: Erlang test suite
-        run: make test_erlang
-        continue-on-error: ${{ matrix.development }}
-      - name: Elixir test suite
-        run: make test_elixir
-        continue-on-error: ${{ matrix.development }}
-      - name: Check reproducible builds
-        run: taskset 1 make check_reproducible
-        if: matrix.otp_release == 'OTP-24.0'
-
-  test_windows:
-    name: Windows, OTP-${{ matrix.otp_release }}, Windows Server 2019
-    strategy:
-      matrix:
-        otp_release: ['22.3']
-    runs-on: windows-2019
-    steps:
-      - name: Configure Git
-        run: git config --global core.autocrlf input
-      - uses: actions/checkout@v2
-        with:
-          fetch-depth: 50
-      - name: Cache Erlang/OTP package
-        uses: actions/cache@v2
-        with:
-          path: C:\Users\runneradmin\AppData\Local\Temp\chocolatey\erlang
-          key: OTP-${{ matrix.otp_release }}-windows-2019
-      - name: Install Erlang/OTP
-        run: choco install -y erlang --version ${{ matrix.otp_release }}
-      - name: Compile Elixir
-        run: |
-          remove-item '.git' -recurse -force
-          make compile
-      - name: Build info
-        run: bin/elixir --version
-      - name: Check format
-        run: make test_formatted && echo "All Elixir source code files are properly formatted."
-      - name: Erlang test suite
-        run: make --keep-going test_erlang
-      - name: Elixir test suite
-        run: |
-          del c:/Windows/System32/drivers/etc/hosts
-          make --keep-going test_elixir
-
-  check_posix_compliant:
-    name: Check POSIX-compliant
-    runs-on: ubuntu-18.04
-    steps:
-      - uses: actions/checkout@v2
-        with:
-          fetch-depth: 50
-      - name: Install Shellcheck
-        run: |
-          sudo apt update
-          sudo apt install -y shellcheck
-      - name: Check POSIX-compliant
-        run: |
-          shellcheck -e SC2039,2086 bin/elixir && echo "bin/elixir is POSIX compliant"
-          shellcheck bin/elixirc && echo "bin/elixirc is POSIX compliant"
-          shellcheck bin/iex && echo "bin/iex is POSIX compliant"

.gitignore

@@ -1,13 +1,17 @@
-/doc/
-/lib/*/ebin/
-/lib/*/_build/
-/lib/*/tmp/
+/doc
+/ebin
+/lib/*/ebin/*
+/lib/*/tmp
+/lib/elixir/src/*_lexer.erl
 /lib/elixir/src/*_parser.erl
-/lib/elixir/test/ebin/
+/lib/elixir/src/elixir.app.src
+/lib/elixir/test/ebin
 /man/elixir.1
 /man/iex.1
+/rel/elixir
 /Docs-v*.zip
 /Precompiled-v*.zip
 /.eunit
+/.release
 .elixir.plt
 erl_crash.dump

.travis.yml

@@ -0,0 +1,20 @@
+language: erlang
+
+otp_release:
+  - 18.0
+  - 18.1
+  - 18.2
+  - 18.3
+  - 19.0
+  - 19.1
+
+sudo: false
+
+script: "make compile && rm -rf .git && make test"
+
+notifications:
+  irc: "irc.freenode.org#elixir-lang"
+  recipients:
+    - jose.valim@plataformatec.com.br
+    - eric.meadows.jonsson@gmail.com
+

CHANGELOG.md

@@ -1,383 +1,333 @@
-# Changelog for Elixir v1.13
+# Changelog for Elixir v1.4
 
-The focus behind Elixir v1.13 has been on tooling, mainly tooling related to code formatting, code fragments, code reflection, and code recompilation. A lot of this functionality will directly impact developers working on large codebases and provide meaningful quality of life improvements for those working on Elixir tooling and environments, such as IDEs, notebooks, etc.
+Elixir v1.4 brings new features, enhancements and bug fixes into Elixir. The most notable changes are the addition of the `Registry` module and the `Task.async_stream/3` and `Task.async_stream/5` which aid developers in writing concurrent software. Those two features and a couple other improvements are described in detail below followed by the complete list of changes.
 
-## Semantic recompilation
+## Registry
 
-Elixir v1.13 comes with many improvements to the compiler, so it recompiles your files less frequently. In particular:
+The registry is a local, decentralized and scalable key-value process storage:
 
-  * The digest of the files are considered in addition to their size. This avoids recompiling many files when switching or rebasing branches.
+  * Local because keys and values are only accessible to the current node (opposite to distributed)
+  * Decentralized because there is no single entity responsible for managing the registry
+  * Scalable because performance scales linearly with the addition of more cores upon partitioning
 
-  * Changing your `mix.exs` will no longer trigger a full recompilation, unless you specifically change the configurations used by the Elixir compiler (`:elixirc_paths` and `:elixirc_options`).
+A registry is chosen upon start to have unique or duplicate keys. Every key-value pair is associated to the process registering the key. Keys are automatically removed once the owner process terminates.
 
-  * Changing compile-time configuration files (`config/config.exs` and any other file imported from it) now only recompiles the project files that depend on the reconfigured applications, instead of a full recompilation. However, if you change the configuration of your application itself, the whole project is still recompiled.
+    iex> Registry.start_link(:unique, MyRegistry)
+    iex> {:ok, _} = Registry.register(MyRegistry, "hello", 1)
+    iex> Registry.lookup(MyRegistry, "hello")
+    [{self(), 1}]
 
-  * Adding, updating or removing a dependency now only recompiles the project files that depend on the modified a dependency.
+With the registry, developers can provide dynamic process names, module-function dispatch or even a local pubsub system. See the `Registry` documentation for more information.
 
-  * If your project has both Erlang and Elixir files, changing an Erlang file will now recompile only the Elixir files that depend on it.
+## Syntax coloring
 
-In a nutshell, Elixir went from triggering full recompilations whenever any of `mix.exs`, `config/config.exs`, `src/*`, and `mix.lock` changed on disk to semantic recompilations. Now it only fully recompiles when:
+Elixir v1.4 introduces the ability to syntax color inspected data structures:
 
-  * you change the compilation options in `mix.exs`
-  * you change the configuration for the current project in `config/config.exs`
+    iex> IO.puts inspect([hello: 1, world: "!"], syntax_colors: [atom: :cyan])
+    [hello: 1, world: "!"]
 
-## mix xref
+Coloring is done with ANSI colors as specified in the `IO.ANSI` module.
 
-`mix xref` is a tool that analyzes relationships between files. By analyzing the compile-time and runtime dependencies between files, it allows developers to understand what files have to be recompiled whenever a file changes.
+IEx automatically relies on this feature to provide syntax coloring for evaluated shell results. This behaviour can be configured via the `:syntax_colors` coloring option:
 
-Elixir v1.13 comes with many improvements to `mix xref`, such as:
+    IEx.configure [colors: [syntax_colors: [atom: :cyan, string: :green]]]
 
-  * `mix xref graph` now supports `--label` to be set to "compile-connected", which returns all compile-time dependencies that lead to additional transitive dependencies.
+To disable coloring altogether, pass an empty list to `:syntax_colors`.
 
-  * A new `mix xref trace FILE` subcommand receives a file and returns all dependencies in said file, including the line and what caused said dependency (a function/macro call, an alias, a struct, etc).
+## Calendar
 
-  * All `mix xref` subcommands support the `--fail-above` flag, which allows you to enforce your project has at most a certain number of compile-time cycles, transitive compile-time dependencies, etc.
+Elixir v1.3 introduced new calendar types. This release continues evolving the Calendar APIs by adding functions for comparing, adding and calculating the difference between types, retrieve the `day_of_week/1`, check if the current date is a `leap_year?/1` and more.
 
-  * `mix xref graph` now supports multiple `--sink` and `--source` to be given.
+## Task.async_stream
 
-With these improvements, it has become simpler to understand the impact code recompilation has in our codebases and how to limit it.
+When there is a need to traverse a collection of items concurrently, Elixir developers often resort to tasks:
 
-## Code fragments
+    collection
+    |> Enum.map(&Task.async(SomeMod, :function, [&1]))
+    |> Enum.map(&Task.await/1)
 
-The `Code` module got a companion module called `Code.Fragment`, which hosts functions that work on incomplete code, as is often the scenario in editors, interactive shells, etc. The module contains different heuristics to analyze the source code and return context informational.
+While the snippet above works fine in many occasions, for large collections it will spawn and run concurrently as many tasks as there are items in the collection.
 
-Thanks to these improvements, `IEx`' autocomplete got several quality of life improvements, such as the autocompletion of sigils, structs, and paths. For example, typing `~<TAB>` now shows:
+`Task.async_stream/3` and `Task.async_stream/5` allows developers to process collections concurrently while controlling the maximum amount of concurrent tasks:
 
-```iex
-iex(1)> ~
-~C (sigil_C)    ~D (sigil_D)    ~N (sigil_N)    ~R (sigil_R)
-~S (sigil_S)    ~T (sigil_T)    ~U (sigil_U)    ~W (sigil_W)
-~c (sigil_c)    ~r (sigil_r)    ~s (sigil_s)    ~w (sigil_w)
+    collection
+    |> Task.async_stream(SomeMod, :function, [], max_concurrency: System.schedulers_online)
 
-```
+The `Task.async_stream` functions are also lazy, allowing developers to partially consume the stream until a condition is reached. Furthermore, `Task.Supervisor.async_stream/4` and `Task.Supervisor.async_stream/6` can be used to ensure the concurrent tasks are spawned under a given supervisor.
 
-Adding the sigil letter and pressing tab then shows the available delimiters:
+## Application inference
 
-```iex
-iex(1)> ~r
-"      """    '      '''    (      /      <      [      {      |
+Mix v1.4 now automatically infers the list of applications that are required on runtime from your dependencies list.
 
-```
+In previous Mix versions, most of your dependencies had to be added both to your dependencies list and applications list. Here is how a `mix.exs` would look like:
 
-Similarly, `%<TAB>` now shows only the available structs (exceptions excluded), instead of all modules:
+    def application do
+      [applications: [:logger, :plug, :postgrex]]
+    end
 
-```elixir
-iex(1)> %File.St
-File.Stat      File.Stream
-```
+    def deps do
+      [{:plug, "~> 1.2"},
+       {:postgrex, "~> 1.0"}]
+    end
 
-Once you define the struct, you can hit `tab` to show all struct fields available:
+This was error prone as many developers would not list their dependencies in their applications list.
 
-```elixir
-iex(1)> %URI{
-authority:    fragment:     host:         path:         port:
-query:        scheme:       userinfo:
-```
+Mix v1.4 now automatically infers your applications list as long as you leave the `:applications` key empty. The `mix.exs` above can be rewritten to:
 
-As you fill a field in, the already filled fields no longer show up:
+    def application do
+      [extra_applications: [:logger]]
+    end
 
-```elixir
-iex(1)> %URI{path: "/example",
-authority:    fragment:     host:         port:         query:
-scheme:       userinfo:
-```
+    def deps do
+      [{:plug, "~> 1.2"},
+       {:postgrex, "~> 1.0"}]
+    end
 
-Along the same lines, `SyntaxError` and `TokenMissingError` were improved to show a code snippet whenever possible:
+With the above, Mix will automatically build your application list based on your dependencies. Applications that are part of Erlang or Elixir that are required at runtime, such as `:logger`, must be added to the `:extra_applications` list. All extra applications will be included in the application list.
 
-```elixir
-$ elixir -e "hello + * world"
-** (SyntaxError) nofile:1:9: syntax error before: '*'
-    |
-  1 | hello + * world
-    |         ^
-```
+Finally, if there is a dependency you don't want to include in the application runtime list, you can do so by specifying the `runtime: false` option:
 
-Finally, new compilation tracers have been added, alongside a handful of functions in `Module` to retrieve module metadata, which can be used to enrich suggestions in programming environments.
+    {:distillery, "> 0.0.0", runtime: false}
 
-## Extended code formatting
+We hope this feature provides a more streamlined workflow for developers who are building releases for their Elixir projects.
 
-The `mix format` task has been augmented with the notion of plugins. Plugins can teach the formatter how to format new files and how to format sigils, via the `Mix.Tasks.Format` behaviour.
+## Mix install from SCM
 
-For example, imagine that your project uses Markdown in two distinct ways: via a custom `~M` sigil and via files with the `.md` and `.markdown` extensions. A custom plugin would look like this:
+Mix v1.4 can now install escripts and archives from both Git and Hex, providing you with even more options for distributing Elixir code.
 
-```elixir
-defmodule MixMarkdownFormatter do
-  @behaviour Mix.Tasks.Format
+This makes it possible to distribute CLI applications written in Elixir by publishing a package which builds an escript to Hex. [`ex_doc`](https://hex.pm/packages/ex_doc) has been updated to serve as an example of how to use this new functionality.
 
-  def features(_opts) do
-    [sigils: [:M], extensions: [".md", ".markdown"]]
-  end
+Simply running:
 
-  def format(contents, opts) do
-    # logic that formats markdown
-  end
-end
-```
+    mix escript.install hex ex_doc
 
-Now any application can use your formatter as follows:
+will fetch `ex_doc` and its dependencies, build them, and then install `ex_doc` to `~/.mix/escripts` (by default). After adding `~/.mix/escripts` to your `PATH`, running `ex_doc` is as simple as:
 
-```elixir
-# .formatter.exs
-[
-  # Define the desired plugins
-  plugins: [MixMarkdownFormatter],
-  # Remember to update the inputs list to include the new extensions
-  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}", "posts/*.{md,markdown}"]
-]
-```
+    ex_doc
 
-Finally, the `Code` module has also been augmented with two functions: `Code.string_to_quoted_with_comments/2` and `Code.quoted_to_algebra/2`. Those functions allow someone to retrieve the Elixir AST with their original source code comments, and then convert this AST to formatted code. In other words, those functions provide a wrapper around the Elixir Code Formatter, supporting developers who wish to create tools that directly manipulate and custom format Elixir source code.
+You can now also install archives from Hex in this way. Since they are fetched and built on the user's machine, they do not have the same limitations as pre-built archives. However, keep in mind archives run alongside every Mix project, which may lead to conflicts. For this reason, escripts is the preferred format.
 
-## v1.13.3 (2022-02-09)
+It is also possible to install escripts and archives by providing a Git/GitHub repo. See `mix help escript.install` and `mix help archive.install` for more details.
+
+## v1.4.3 (2017-05-15)
+
+This version includes changes that make Elixir fully compatible with Erlang OTP 20-rc.1.
 
 ### 1. Enhancements
 
+#### Elixir
+
+  * [Kernel] Improve compilation time for modules with many clauses
+  * [Map] Warn when attempting to override `__struct__` key
+  * [Regex] Add `recompile/1` and `recompile!/1` to ease transition to OTP 20 for archives and stored regexes
+
+#### Logger
+
+  * [Logger.Translator] Handle OTP 20 GenServer log messages
+
 #### Mix
 
-  * [mix format] Supply file and line to formatter plugins
-  * [mix format] Support embedded Elixir expressions inside formatter plugins
+  * [mix compile] Recompile projects if OTP version changes
 
 ### 2. Bug fixes
 
 #### Elixir
 
-  * [Code] Fix duplicate bindings causing errors during evaluation
-  * [Kernel] Make sure signatures stored in the Documentation chunk does not contain newlines
-  * [Kernel] Fix infinite loop when compiling guards with recursive map access
-  * [Macro] Fix error on `Macro.to_string/1` when the plain alias `Elixir` is given
-  * [String] Fix error for certain codepoint combinations in `String.split_at/2`
+  * [Kernel] Fix code generation when non-binary bitstrings are in AST
+  * [Record] Properly escape fields passed to `defrecord`
+
+#### ExUnit
+
+  * [ExUnit.Diff] Do not fail when comparing maps with nil or boolean keys
+
+#### IEx
+
+  * [IEx.Helpers] Do not log exits on `IEx.Helpers.c/2` failures
 
 #### Mix
 
-  * [mix compile] Recompile project files when exports from dependencies change
-  * [mix test] Fix total coverage always showing in red even when above the threshold
+  * [mix archive.install] Detect proper path on URLs with query strings
+  * [mix loadpaths] Do not assume all paths in loadpaths exist
 
-## v1.13.2 (2022-01-13)
 
-### 1. Enhancements
+## v1.4.2 (2017-02-16)
 
-#### Mix
+### 1. Bug fixes
 
-  * [mix format] Allow plugins to also format `.ex` and `.exs` files
-  * [mix release] Allow bypassing application mode validation in release spec
-  * [mix test] Print a message when the suite fails due to the coverage threshold
+#### EEx
 
-### 2. Bug fixes
+  * [EEx] Support middle expressions on trim mode
 
 #### Elixir
 
-  * [Code] Do not emit warnings on `Code.Fragment.container_cursor_to_quoted/2`
-  * [Kernel] Fix a crash when a for-comprehension with `:uniq` was used inside another comprehension with `:uniq`
-  * [Kernel] Ensure `env.context_modules` is properly set inside optimized `defmodule`
-  * [Keyword] Deprecate the recently added `Keyword.map/2` as it is equivalent to `Keyword.new/2`
-  * [Map] Deprecate the recently added `Map.map/2` as it is equivalent to `Map.new/2`
-  * [Protocol] Warn on zero arity callbacks inside protocols
+  * [Calendar] Correct typo on Calendar types
+  * [Kernel] Ensure redefined functions point to the proper source
+  * [OptionParser] Add `:allow_nonexistent_atoms` to support unsafe behaviour prior to v1.4
+  * [Stream] Allow consuming multiple items from suspended enumerable in `Stream.transform/3`
+  * [String] Incorporate new grapheme rules in Unicode 9
 
-## v1.13.1 (2021-12-14)
+#### IEx
+
+  * [IEx.Autocomplete] Do not crash on aliases which are not known at compile time
+
+#### Mix
+
+  * [Mix.Umbrella] Ensure umbrella projects can depend on other umbrella projects
+  * [Mix.Archive] Ensure previous archives with `.ez` extension are deleted
+
+## v1.4.1 (2017-01-26)
 
 ### 1. Bug fixes
 
 #### Elixir
 
-  * [Code] Do not show code snippets in `SyntaxError` and `TokenMissingError` if line is empty
-  * [Exception] Do not fail blaming `ArgumentError` for improper lists on `apply/3`
-  * [Macro] Set a max `line_length` for `Macro.to_string/1`
-  * [Macro] Fix formatting of lists on module attributes for `Macro.to_string/1`
-  * [String] Fix incorrect codepoint byte counting in `slice` with negative positions in ranges
-  * [Task] Ensure async streams can be consumed from another process than the one that creates them
-  * [URI] Undeprecate `URI.parse/1` as `URI.new/1` is too strict in many common cases
-  * [URI] Make sure `URI.new/1` returns nil for empty paths
+  * [Kernel] Remove warning when making private functions overridable
+  * [Path] Ensure `Path.join/1` returns strings for lists of one element
+  * [Regex] Ensure `Regex.escape/1` also escapes `-`
 
 #### IEx
 
-  * [IEx] Make sure the `--version` flag halts IEx
+  * [IEx] Disable ANSI detection for powershell to avoid false positives
 
 #### Mix
 
-  * [Mix] Make protocol consolidation part of the `Mix.install/2` cache
+  * [Mix.Make] Run `make clean` for `erlang.mk`
+  * [Mix.Rebar] Support all of rebar3 dependency package declaration
+  * [Mix.Rebar] Only pass overrides from parent to child in Rebar dep
 
-## v1.13.0 (2021-12-03)
+## v1.4.0 (2017-01-05)
 
 ### 1. Enhancements
 
-#### EEx
-
-  * [EEx] Add `:parser_options` to EEx functions
-
 #### Elixir
 
-  * [Calendar] Add `c:Calendar.year_of_era/3` to support calendars where the beginning of a new era does not align with the beginning of a new year
-  * [CLI] Support `--short-version` on the CLI that does not boot the VM
-  * [Code] Add `Code.string_to_quoted_with_comments/2` and `Code.quoted_to_algebra/2`
-  * [Code] Add more `:token_metadata` to aliases and remote calls when parsing strings
-  * [Code] Add `Code.Fragment` module to provide best-effort information from code fragments. The module currently provides an updated `Code.Fragment.cursor_context/2` with operator support and `Code.Fragment.surround_context/2` which looks at a given position in a fragment and find its surrounding delimiters
-  * [Code] Allow custom sigil formatting on `Code.format_string!/2`
-  * [Code] Add `{:on_module, bytecode, :none}` trace to compilation tracers
-  * [Enum] Optimize `Enum.concat/1` for lists of lists
-  * [Enum] Add `Enum.slide/3`
-  * [Exception] Better format Elixir exceptions in Erlang
-  * [Inspect] Allow default inspect fun to be set globally with `Inspect.Opts.default_inspect_fun/1`
-  * [IO] Allow `:eof` to be given as limit to `IO.getn/2`
-  * [Kernel] Support the `:sigils` option in `import Mod, only: :sigils` and allow the sigil modifiers to be also digits
-  * [Kernel] Make `get_in` consistently abort and return `nil` when `nil` values are found (previously Elixir would raise an error in this case). This allows a user to use `get_in` as a safe navigation operator.
-  * [Kernel] Improve compilation times by reducing the amount of copies of the AST across compiler processes
-  * [Kernel] Raise if trying to define a module with a slash in its name
-  * [Kernel] Warn when `?\` is used and there is no need for a escape character
-  * [Kernel] Track structs in typespecs as export deps instead of compile-time deps
-  * [Kernel] Add power operator (`**/2`)
-  * [Keyword] Add `Keyword.validate/2`
-  * [Keyword] Implement `Keyword.filter/2` and `Keyword.map/2`
-  * [List] Add `List.keyfind!/3`
-  * [Macro] Add `Macro.prewalker/1` and `Macro.postwalker/1`
-  * [Macro.Env] Add the following reflection functions: `required?/2`, `lookup_import/2`, `fetch_alias/2`, and `fetch_macro_alias/2`
-  * [Map] Implement `Map.filter/2` and `Map.map/2`
-  * [Module] Support `:nillify_clauses` in `Module.get_definition/3`
-  * [Module] Add `Module.attributes_in/1` and `Module.overridables_in/1`
-  * [OptionParser] Add "did you mean?" suggestions to `OptionParser.ParseError` messages
-  * [Record] Add record reflection via `@__records__`
-  * [Task] Add `Task.completed/1`
-  * [Task] Add `Task.ignore/1` to keep a task running but ignoring all of its results
-  * [Task] Reduce the amount of copying `Task.async*` functions
-  * [URI] Add `URI.new/1` and `URI.new!/1`
+  * [Calendar] Add `Date.compare/2`, `Time.compare/2`, `NaiveDateTime.compare/2` and `DateTime.compare/2`
+  * [Calendar] Support `NaiveDateTime.add/3` and `NaiveDateTime.diff/3` for adding seconds (up to microseconds) as well as the difference between two NaiveDateTimes in seconds (up to microseconds)
+  * [Calendar] Add `Date.leap_year?/1` and `Date.day_of_week/1`
+  * [Calendar] Ensure `Date`, `Time` and `NaiveDateTime` APIs work with any struct that provides the same set of fields as their respective struct. For example, a `NaiveDateTime` can be given to `Date` since it contains a superset of the fields in the `Date` struct
+  * [Calendar] Add `Time.utc_now/0` and `NaiveDateTime.utc_now/0`
+  * [Enum] Add `Enum.map_every/2` that invokes the given function with every nth item
+  * [Enum] Add `min/2`, `max/2`, `min_max/2`, `min_by/3`, `max_by/3`, and `min_max_by/3` that allow a function specifying the default value when the enumerable is empty
+  * [Enum] Introduce `Enum.zip/1` to zip multiple entries at once
+  * [Float] Introduce `Float.ratio/1` that returns a tuple with the numerator and denominator as integers to retrieve the given float
+  * [GenServer] Log warn on default `handle_info/2` implementation
+  * [Inspect] Support syntax coloring via the `:syntax_color` option
+  * [Integer] `Integer.digits/2` now accepts negative integers
+  * [Integer] Add `Integer.mod/2` and `Integer.floor_div/2`
+  * [IO] Add `:label` option to `IO.inspect/2` to help distinguish multiple `IO.inspect/2` calls.
+  * [Kernel] Recognize merge conflict markers in source and provide a readable error message
+  * [Kernel] Warn on unused module attributes
+  * [Kernel] Improve compiler message on unexpected end of line
+  * [Kernel] Raise `BadBooleanError` when a non-boolean is given on the left-hand side of `and`/`or`
+  * [List] Add `List.pop_at/3`
+  * [List] Add `List.myers_difference/2`
+  * [OptionParser] Expand multi-letter aliases in `OptionParser`
+  * [Process] Add `Process.send_after/4`
+  * [Process] Improve error messages on `Process.register/2` errors
+  * [Registry] Add a local, decentralized and scalable key-value process storage
+  * [Stream] Add `Stream.map_every/2` that invokes the given function with every nth item
+  * [Stream] Introduce `Stream.zip/1` to lazily zip multiple entries at once
+  * [String] Update to Unicode 9.0.0
+  * [Task] Add `Task.async_stream/3` and `Task.async_stream/5` as well as the supervised versions `Task.Supervisor.async_stream/4` and `Task.Supervisor.async_stream/6`
+  * [URI] Allow 0 as URI scheme default port
 
 #### ExUnit
 
-  * [ExUnit] Show hint if comparing different but equivalent strings
-  * [ExUnit.CaptureIO] Add `with_io/3` to return result with captured io
-  * [ExUnit.CaptureLog] Add `with_log/2` to return result with captured logs
+  * [ExUnit.Diff] Use red or green background for whitespace-only diffs
+  * [ExUnit.Doctest] Allow inspected structures with multiples lines and unicode characters in the doctest result
+  * [ExUnit.Formatter] Replace lhs/rhs with left/right in the formatter for clarity
 
 #### IEx
 
-  * [IEx.Autocomplete] Add path autocompletion whenever when the cursor follows `"./` or `"/` or `"DRIVER:` where `DRIVER` is a single letter
-  * [IEx.Autocomplete] Add autocompletion for sigils, struct names, and struct fields
-  * [IEx.Helpers] Allow multiple modules to be given to `r/1`
-
-#### Logger
-
-  * [Logger] Add `Logger.put_application_level/2`
-  * [Logger] Print all log levels in accordance to Erlang/OTP. This also means `[warn]` is now shown as `[warning]`
+  * [IEx.Autocomplete] Stop appending a trailing dot when autocompleting modules in IEx
+  * [IEx.Autocomplete] Support autocompletion for structs
+  * [IEx.Autocomplete] Improve IEx autocomplete to support navigating map atom keys
+  * [IEx.Helpers] `c/1` now compiles in memory by default to avoid common issue where `.beam` files remain at projects root directory
+  * [IEx.Helpers] Add info about protocols in `i/1`
+  * [IEx.Server] Support interrupting IEx evaluation through the Ctrl+G prompt
 
 #### Mix
 
-  * [Mix] Add `MIX_INSTALL_FORCE` environment variable support
-  * [Mix] Support `:config` and `:system_env` in `Mix.install/2`
-  * [Mix] Add `Mix.installed?/0`
-  * [Mix.Shell] Add `:default` option to `Mix.Shell.yes?`
-  * [mix archive.install] Run `loadconfig` before building archive
-  * [mix compile] Move Elixir version check to before deps are compiled, in order to give feedback earlier
-  * [mix compile.elixir] Do not recompile files if their modification time change but their contents are still the same and the .beam files are still on disk
-  * [mix compile.elixir] Do not recompile all Elixir sources when Erlang modules change, only dependent ones
-  * [mix compile.elixir] Do not recompile Elixir files if `mix.exs` changes, instead recompile only files using `Mix.Project` or trigger a recompilation if a compiler option changes
-  * [mix compile.elixir] Only recompile needed files when a dependency is added, updated or removed
-  * [mix compile.elixir] Only recompile needed files when a dependency is configured
-  * [mix deps] Add `:subdir` option to git deps
-  * [mix escript.install] Run `loadconfig` before building escript
-  * [mix format] Support `:plugins` in `mix format` that can hook into custom extensions and sigils
-  * [mix format] Add `Mix.Tasks.Format.formatter_for_file/2`
-  * [mix local.rebar] No longer support `sub_dirs` in Rebar 2 to help migration towards Rebar 3
-  * [mix local.rebar] Support `--if-missing` option when installing Rebar
-  * [mix local.rebar] Set `REBAR_PROFILE=prod` when compiling Rebar dependencies
-  * [mix test] Support `--profile-require=time` to profile the time loading test files themselves
-  * [mix test] Allow filtering modules from coverage using regex
-  * [mix test] Allow the exit status of ExUnit to be configured and set the default to 2
-  * [mix test] Exit with a status of 3 when coverage falls below threshold
-  * [mix test] Write failed manifest when suite fails due to --warnings-as-errors
-  * [mix test] Ignore `MIX_TEST_PARTITION` when partitions set to 1
-  * [mix xref] Support multiple sinks and sources in `mix xref graph`
-  * [mix xref] Add `trace` subcommand to print compilation dependencies between files
-  * [mix xref] Add `--fail-above` option to `mix xref`
-  * [mix xref] Add `--label compile-connected` to `mix xref`
+  * [mix archive] Compress archive files built by `mix archive` as they are now unzipped during installation
+  * [mix archive] Install from SCM
+  * [mix compile] Automatically infer the list of applications for Mix projects
+  * [mix cmd] Add the ability to specify one or more apps in `mix cmd`
+  * [mix deps] Warn if there are non-applications in the `apps` directory for umbrella projects
+  * [mix deps] Add warning for invalid paths on `mix deps.clean`
+  * [mix deps] Add `Mix.Project.apps_paths` that returns the paths to children applications in umbrella projects
+  * [mix deps] Add `MIX_REBAR` environment variable for overriding local rebar
+  * [mix escript] Install from SCM
+  * [mix new] Check directory existence in `mix new` and ask how to proceed if one exists
+  * [mix new] Applications built with the `--sup` flag now have an individual module to work as application callback
+  * [mix test] Add `--formatter` option to `mix test`
+  * [mix xref] Provide "did you mean?" suggestions for `mix xref`
 
 ### 2. Bug fixes
 
-#### EEx
-
-  * [EEx] Accept comments in EEx between do and the first clause
-  * [EEx] Accept EEx expressions where `->` is followed by newline
-
 #### Elixir
 
-  * [Application] Allow any expression as first argument of `compile_env`
-  * [Application] Warn if `Application.compile_env` or `Application.compile_env!` are called without a require
-  * [Code] Make sure `:static_atoms_encoder` in `Code.string_to_quoted/2` also applies to quoted keyword keys
-  * [Code] Ensure bindings with no context are returned as atoms instead of `{binding, nil}` in eval operations
-  * [Inspect] Fix a bug when inspecting a non-binary bitstring with colors
-  * [Kernel] Reject bidirectional formatting characters in strings and comments
-  * [Kernel] Support escaping of terminators in uppercase sigils heredocs for consistency
-  * [Kernel] Raise if `__CALLER__` or `__ENV__` or `__STACKTRACE__` are used in match
-  * [Kernel] Improve error message on invalid argument for `byte_size` from binary concat
-  * [Kernel] Raise when aliasing non-Elixir modules without `:as`
-  * [Kernel] Allow `unquote_splicing` inside `%{...}` without parens
-  * [Kernel] Ensure that waiting on a struct expansion inside a typespec is correctly tracked as waiting time in the compiler
-  * [Kernel] Correctly parse the atom `.` as a keyword list key
-  * [Kernel] Do not leak variables from the first generator in `with` and `for` special forms
-  * [Kernel] Fix column number on strings with NFD characters
-  * [Kernel] Fix a bug where a combination of dynamic line in `quote` with `unquote` of remote calls would emit invalid AST metadata
-  * [OptionParser] Validate switch types/modifiers early on to give more precise feedback
-  * [Protocol] Add `defdelegate` to the list of unallowed macros inside protocols as protocols do not allow function definitions
-  * [Protocol] Warn if `@callback`, `@macrocallback` and `@optional_callbacks` are defined inside protocol
-  * [Protocol] Ensure protocol metadata is deterministic on consolidation
-  * [Range] Always show step when range is descending
-  * [String] Update Unicode database to version 14.0
-  * [URI] Only percent decode if followed by hex digits (according to https://url.spec.whatwg.org/#percent-decode)
-  * [Version] Ensure proper precedence of `and`/`or` in version requirements
+  * [Access] Do not accept nils in `Access.key/1` and `Access.key/2` in favor of explicit default values (or Access.key!/1 if you expect the key to always be available)
+  * [Float] Avoid multiple roundings in `Float.ceil/2`, `Float.floor/2` and `Float.round/2`
+  * [Kernel] Don't crash in `macro_exported?/3` when dealing with Erlang modules
+  * [Kernel] Ensure locals calls are rewritten when calling a local function or macro from inside a module
+  * [Kernel] Annotate the context for variables as zero-arity funs in quotes
+  * [Kernel.SpecialForms] Ensure comprehensions with guards and filters keep proper ordering,
+  * [Kernel.SpecialForms] Produce meaningful warning when with's else clauses have no effect
+  * [Macro] Wrap fn calls in parens in `Macro.to_string/2`
+  * [Macro] Do not print aliases as keys inside keyword lists in `Macro.to_string/2`
+  * [OptionParser] Support options in `OptionParser.to_argv/2` to ensure `:count` switches are correctly encoded
+  * [Stream] Ensure `Stream.take/2` does not consume next element on `:suspend`
+  * [String] Fix infinite recursion in `String.replace_leading/3` and `String.replace_trailing/3` when given an empty string
+  * [Task] Fix `Task.shutdown/1,2` infinite block when task has no monitor
+  * [Task] Ensure task cannot link after parents unlinks
 
 #### ExUnit
 
-  * [ExUnit] Fix formatter and counters from `ExUnit.run/0` to consider all tests in a module whenever if a module's `setup_all` fails
-  * [ExUnit] Allow doctests newlines to be terminated by CRLF
+  * [ExUnit] Fix a race condition in `assert_receive` where we would assert a message was not received but show it in the list of messages when the message is delivered right after the timeout value
+
+### IEx
+
+  * [IEx.Helpers] Purge consolidated protocols before and after `recompile/0`
+
+### Mix
+
+  * [Mix.Dep] Use `gmake` on FreeBSD instead of `make` when compiling make dependencies
+  * [Mix.Project] Only copy files from source when they're newer than destination (for Windows machines)
+  * [Mix.Task] Ensure non-recursive tasks inside umbrella are reenabled
+
+### 3. Soft deprecations (no warnings emitted)
+
+#### Elixir
+
+  * [Enum] `Enum.partition/2` has been deprecated in favor of `Enum.split_with/2`
+  * [System] Deprecate plural time units in favor of singular ones to align with future Erlang releases
+
+#### ExUnit
+
+  * [ExUnit] Using GenEvent to implement ExUnit formatters is deprecated. Please use the new `GenServer` based formatters instead
+
+### 4. Deprecations
+
+#### Elixir
+
+  * [Access] `Access.key/1` is deprecated due to erratic behaviour for missing keys, please use `Access.key/2` instead with proper default values
+  * [Behaviour] The `Behaviour` module is deprecated. Callbacks may now be defined directly via the `@callback` attribute
+  * [Enum] Deprecate `Enum.uniq/2` in favor of `Enum.uniq_by/2`
+  * [Float] `Float.to_char_list/2` and `Float.to_string/2` are deprecated (use the `:erlang.float_to_list/2` and `:erlang.float_to_binary/2` functions if such conversions are desired)
+  * [Kernel] Deprecate support for making private functions overridable. Overridable functions must always be public as they must be contracts
+  * [Kernel] Warn if variable is used as a function call
+  * [OptionParser] Deprecate aliases with multiple letters, such as `-abc`
+  * [Set] Deprecate the `Set` module
+  * [Stream] Deprecate `Stream.uniq/2` in favor of `Stream.uniq_by/2`
 
 #### IEx
 
-  * [IEx] Fix the loss of `.iex.exs` context after a pry session
-  * [IEx] Stop evaluator before exiting IEx server to avoid evaluators leaking
-
-#### Logger
-
-  * [Logger] Raise clear error message for invalid `:compile_time_purge_matching` configuration
-  * [Logger] Fix a bug where Logger would not reset its discard counter under some scenarios
+  * [IEx.Helpers] `import_file/2` is deprecated in favor of `import_file_if_available/1`
 
 #### Mix
 
-  * [mix compile.elixir] Track transitive runtime dependencies coming from local/path dependencies
-  * [mix compile.elixir] Recompile file if `@external_resource` is deleted
-  * [mix compile.elixir] Print number of compiling files on all compiler cycles. This will make the `Compiling N files (.ex)` show up multiple times if necessary
-  * [mix deps] Raise if local dep is unavailable while compiling
-  * [mix deps.unlock] Fix blank output when unlocking a dependency that is not locked
-  * [mix local.install] Do not respect `MIX_DEPS_PATH` for install commands
-  * [mix release] Improve release scripts by making sure shell errors cascade (this is done by avoiding exporting and defining variables in a single step)
-  * [mix release] Do not boot release if `RELEASE_COOKIE` is empty
-  * [mix release] Allow releases running as a daemon to be restarted
-  * [mix release] Raise proper error message when non-serializable values are in configs
-  * [mix test] Fix coverage engine to also tag `case`, `cond`, and `receive` branches where the right side is a literal
+  * [Mix.Utils] `underscore/1` and `camelize/1` are deprecated in favor of `Macro.underscore/1` and `Macro.camelize/1`
 
-### 3. Soft-deprecations (no warnings emitted)
+## v1.3
 
-#### Elixir
-
-  * [Code] Environment options in `Code.eval_quoted/3` and `Code.eval_string/3`, such as `:aliases` and `:tracers`, have been deprecated in favor of passing an environment
-  * [IO] `:all` on `IO.getn` is deprecated in favor of `:eof`
-  * [URI] `URI.parse/1` is deprecated in favor of `URI.new/1` and `URI.new!/1`
-
-#### Mix
-
-  * [mix format] `Mix.Tasks.Format.formatter_opts_for_file/2` is deprecated in favor of `Mix.Tasks.Format.formatter_for_file/2`
-
-### 4. Hard-deprecations
-
-#### Elixir
-
-  * [Code] `Code.cursor_context/2` is deprecated, use `Code.Fragment.cursor_context/2` instead
-  * [Macro] `Macro.to_string/2` is deprecated, use `Macro.to_string/1` instead
-  * [System] `System.get_pid/0` is deprecated, use `System.pid/0` instead
-  * [Version] Using `!` or `!=` in version requirements is deprecated, use `~>` or `>=` instead
-
-#### Mix
-
-  * [mix escript.build] `:strip_beam` option is deprecated in favor of `:strip_beams`
-  * [Mix] `:exit_code` in `Mix.raise/2` has been deprecated in favor of `:exit_status`
-  * [Mix.Config] `Mix.Config` is deprecated in favor of `Config` module
-
-## v1.12
-
-The CHANGELOG for v1.12 releases can be found [in the v1.12 branch](https://github.com/elixir-lang/elixir/blob/v1.12/CHANGELOG.md).
+The CHANGELOG for v1.3 releases can be found [in the v1.3 branch](https://github.com/elixir-lang/elixir/blob/v1.3/CHANGELOG.md).

CODE_OF_CONDUCT.md

@@ -13,23 +13,17 @@ The goal of the Code of Conduct is to specify a baseline standard of behavior so
 These are the values Elixir developers should aspire to:
 
   * Be friendly and welcoming
-  * Be kind
+  * Be patient
     * Remember that people have varying communication styles and that not everyone is using their native language. (Meaning and tone can be lost in translation.)
-    * Interpret the arguments of others in good faith, do not seek to disagree.
-    * When we do disagree, try to understand why.
   * Be thoughtful
     * Productive communication requires effort. Think about how your words will be interpreted.
     * Remember that sometimes it is best to refrain entirely from commenting.
   * Be respectful
     * In particular, respect differences of opinion. It is important that we resolve disagreements and differing views constructively.
-  * Be constructive
-    * Avoid derailing: stay on topic; if you want to talk about something else, start a new conversation.
-    * Avoid unconstructive criticism: don't merely decry the current state of affairs; offer — or at least solicit — suggestions as to how things may be improved.
-    * Avoid harsh words and stern tone: we are all aligned towards the well-being of the community and the progress of the ecosystem. Harsh words exclude, demotivate, and lead to unnecessary conflict.
-    * Avoid snarking (pithy, unproductive, sniping comments).
-    * Avoid microaggressions (brief and commonplace verbal, behavioral and environmental indignities that communicate hostile, derogatory or negative slights and insults towards a project, person or group).
-  * Be responsible
-    * What you say and do matters. Take responsibility for your words and actions, including their consequences, whether intended or otherwise.
+  * Avoid destructive behavior
+    * Derailing: stay on topic; if you want to talk about something else, start a new conversation.
+    * Unconstructive criticism: don't merely decry the current state of affairs; offer (or at least solicit) suggestions as to how things may be improved.
+    * Snarking (pithy, unproductive, sniping comments).
 
 The following actions are explicitly forbidden:
 
@@ -45,13 +39,13 @@ If you participate in or contribute to the Elixir ecosystem in any way, you are
 
 Explicit enforcement of the Code of Conduct applies to the official mediums operated by the Elixir project:
 
-* The [official GitHub projects][1] and code reviews.
+* The official GitHub projects and code reviews.
 * The official elixir-lang mailing lists.
-* The **[#elixir][2]** IRC channel on [Libera.Chat][3].
+* The #elixir-lang IRC channel on Freenode.
 
-Other Elixir activities (such as conferences, meetups, and unofficial forums) are encouraged to adopt this Code of Conduct. Such groups must provide their own contact information.
+Other Elixir activities (such as conferences, meetups, and other unofficial forums) are encouraged to adopt this Code of Conduct. Such groups must provide their own contact information.
 
-Project maintainers may block, remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct.
+Project maintainers may remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct.
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by emailing: elixir-lang-conduct@googlegroups.com. All complaints will be reviewed and investigated and will result in a response that is deemed necessary and appropriate to the circumstances. **All reports will be kept confidential**.
 
@@ -59,8 +53,4 @@ Instances of abusive, harassing, or otherwise unacceptable behavior may be repor
 
 ## Acknowledgements
 
-This document was based on the Code of Conduct from the Go project (dated Sep/2021) and the Contributor Covenant (v1.4).
-
-[1]: https://github.com/elixir-lang/
-[2]: https://web.libera.chat/#elixir
-[3]: https://libera.chat/
+This document was based on the Code of Conduct from the Go project with parts derived from Django's Code of Conduct, Rust's Code of Conduct and the Contributor Covenant.

ISSUE_TEMPLATE.md

@@ -0,0 +1,18 @@
+### Precheck
+
+* Do not use the issues tracker for help or support (try Elixir Forum, Stack Overflow, IRC, etc.)
+* For proposing a new feature, please start a discussion on the Elixir Core mailing list
+* For bugs, do a quick search and make sure the bug has not yet been reported
+* Finally, be nice and have fun!
+
+### Environment
+
+* Elixir version (elixir -v):
+* Operating system:
+
+### Current behavior
+
+Include code samples, errors and stacktraces if appropriate.
+
+### Expected behavior
+

LICENSE

@@ -1,176 +1,13 @@
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
+Copyright 2012 Plataformatec
 
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
 
-   1. Definitions.
+      http://www.apache.org/licenses/LICENSE-2.0
 
-      "License" shall mean the terms and conditions for use, reproduction,
-      and distribution as defined by Sections 1 through 9 of this document.
-
-      "Licensor" shall mean the copyright owner or entity authorized by
-      the copyright owner that is granting the License.
-
-      "Legal Entity" shall mean the union of the acting entity and all
-      other entities that control, are controlled by, or are under common
-      control with that entity. For the purposes of this definition,
-      "control" means (i) the power, direct or indirect, to cause the
-      direction or management of such entity, whether by contract or
-      otherwise, or (ii) ownership of fifty percent (50%) or more of the
-      outstanding shares, or (iii) beneficial ownership of such entity.
-
-      "You" (or "Your") shall mean an individual or Legal Entity
-      exercising permissions granted by this License.
-
-      "Source" form shall mean the preferred form for making modifications,
-      including but not limited to software source code, documentation
-      source, and configuration files.
-
-      "Object" form shall mean any form resulting from mechanical
-      transformation or translation of a Source form, including but
-      not limited to compiled object code, generated documentation,
-      and conversions to other media types.
-
-      "Work" shall mean the work of authorship, whether in Source or
-      Object form, made available under the License, as indicated by a
-      copyright notice that is included in or attached to the work
-      (an example is provided in the Appendix below).
-
-      "Derivative Works" shall mean any work, whether in Source or Object
-      form, that is based on (or derived from) the Work and for which the
-      editorial revisions, annotations, elaborations, or other modifications
-      represent, as a whole, an original work of authorship. For the purposes
-      of this License, Derivative Works shall not include works that remain
-      separable from, or merely link (or bind by name) to the interfaces of,
-      the Work and Derivative Works thereof.
-
-      "Contribution" shall mean any work of authorship, including
-      the original version of the Work and any modifications or additions
-      to that Work or Derivative Works thereof, that is intentionally
-      submitted to Licensor for inclusion in the Work by the copyright owner
-      or by an individual or Legal Entity authorized to submit on behalf of
-      the copyright owner. For the purposes of this definition, "submitted"
-      means any form of electronic, verbal, or written communication sent
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+  Unless required by applicable law or agreed to in writing, software
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+  See the License for the specific language governing permissions and
+  limitations under the License.

Makefile

@@ -1,14 +1,10 @@
+REBAR ?= "$(CURDIR)/rebar"
 PREFIX ?= /usr/local
-TEST_FILES ?= "*_test.exs"
 SHARE_PREFIX ?= $(PREFIX)/share
-MAN_PREFIX ?= $(SHARE_PREFIX)/man
-CANONICAL := 1.13/
-CANONICAL ?= master/
-ELIXIRC := bin/elixirc --ignore-module-conflict $(ELIXIRC_OPTS)
+CANONICAL :=
+ELIXIRC := bin/elixirc --verbose --ignore-module-conflict
 ERLC := erlc -I lib/elixir/include
-ERL_MAKE := if [ -n "$(ERLC_OPTS)" ]; then ERL_COMPILER_OPTIONS=$(ERLC_OPTS) erl -make; else erl -make; fi
 ERL := erl -I lib/elixir/include -noshell -pa lib/elixir/ebin
-GENERATE_APP := $(CURDIR)/lib/elixir/generate_app.escript
 VERSION := $(strip $(shell cat VERSION))
 Q := @
 LIBDIR := lib
@@ -19,27 +15,29 @@ INSTALL_DATA = $(INSTALL) -m644
 INSTALL_PROGRAM = $(INSTALL) -m755
 GIT_REVISION = $(strip $(shell git rev-parse HEAD 2> /dev/null ))
 GIT_TAG = $(strip $(shell head="$(call GIT_REVISION)"; git tag --points-at $$head 2> /dev/null | tail -1) )
-SOURCE_DATE_EPOCH_PATH = lib/elixir/tmp/ebin_reproducible
-SOURCE_DATE_EPOCH_FILE = $(SOURCE_DATE_EPOCH_PATH)/SOURCE_DATE_EPOCH
 
-.PHONY: install compile erlang elixir unicode app build_plt clean_plt dialyze test check_reproducible clean clean_residual_files format install_man clean_man docs Docs.zip Precompiled.zip zips
+.PHONY: install compile erlang elixir build_plt clean_plt dialyze test clean install_man clean_man docs Docs.zip Precompiled.zip zips
 .NOTPARALLEL: compile
 
 #==> Functions
 
 define CHECK_ERLANG_RELEASE
-	erl -noshell -eval '{V,_} = string:to_integer(erlang:system_info(otp_release)), io:fwrite("~s", [is_integer(V) and (V >= 22)])' -s erlang halt | grep -q '^true'; \
+	$(Q) erl -noshell -eval '{V,_} = string:to_integer(erlang:system_info(otp_release)), io:fwrite("~s", [is_integer(V) and (V >= 18)])' -s erlang halt | grep -q '^true'; \
 		if [ $$? != 0 ]; then \
-		  echo "At least Erlang/OTP 22.0 is required to build Elixir"; \
-		  exit 1; \
-		fi
+		   echo "At least Erlang 18.0 is required to build Elixir"; \
+		   exit 1; \
+		fi;
 endef
 
 define APP_TEMPLATE
 $(1): lib/$(1)/ebin/Elixir.$(2).beam lib/$(1)/ebin/$(1).app
 
 lib/$(1)/ebin/$(1).app: lib/$(1)/mix.exs
-	$(Q) cd lib/$(1) && ../../bin/elixir -e 'Mix.start(:permanent, [])' -r mix.exs -e 'Mix.Task.run("compile.app", ~w[--compile-path ebin])'
+	$(Q) mkdir -p lib/$(1)/_build/shared/lib/$(1)
+	$(Q) cp -R lib/$(1)/ebin lib/$(1)/_build/shared/lib/$(1)/
+	$(Q) cd lib/$(1) && ../../bin/elixir -e 'Mix.start(:permanent, [])' -r mix.exs -e 'Mix.Task.run("compile.app")'
+	$(Q) cp lib/$(1)/_build/shared/lib/$(1)/ebin/$(1).app lib/$(1)/ebin/$(1).app
+	$(Q) rm -rf lib/$(1)/_build
 
 lib/$(1)/ebin/Elixir.$(2).beam: $(wildcard lib/$(1)/lib/*.ex) $(wildcard lib/$(1)/lib/*/*.ex) $(wildcard lib/$(1)/lib/*/*/*.ex)
 	@ echo "==> $(1) (compile)"
@@ -47,65 +45,51 @@ lib/$(1)/ebin/Elixir.$(2).beam: $(wildcard lib/$(1)/lib/*.ex) $(wildcard lib/$(1
 	$(Q) cd lib/$(1) && ../../$$(ELIXIRC) "lib/**/*.ex" -o ebin
 
 test_$(1): compile $(1)
-	@ echo "==> $(1) (ex_unit)"
-	$(Q) cd lib/$(1) && ../../bin/elixir -r "test/test_helper.exs" -pr "test/**/$(TEST_FILES)";
-endef
-
-define WRITE_SOURCE_DATE_EPOCH
-$(shell mkdir -p $(SOURCE_DATE_EPOCH_PATH) && bin/elixir -e \
-  'IO.puts System.build_info()[:date] \
-   |> DateTime.from_iso8601() \
-   |> elem(1) \
-   |> DateTime.to_unix()' > $(SOURCE_DATE_EPOCH_FILE))
-endef
-
-define READ_SOURCE_DATE_EPOCH
-$(strip $(shell cat $(SOURCE_DATE_EPOCH_FILE)))
+	@ echo "==> $(1) (exunit)"
+	$(Q) cd lib/$(1) && ../../bin/elixir -r "test/test_helper.exs" -pr "test/**/*_test.exs";
 endef
 
 #==> Compilation tasks
 
-APP := lib/elixir/ebin/elixir.app
-PARSER := lib/elixir/src/elixir_parser.erl
-KERNEL := lib/elixir/ebin/Elixir.Kernel.beam
-UNICODE := lib/elixir/ebin/Elixir.String.Unicode.beam
+KERNEL:=lib/elixir/ebin/Elixir.Kernel.beam
+UNICODE:=lib/elixir/ebin/Elixir.String.Unicode.beam
 
 default: compile
 
-compile: erlang $(APP) elixir
+compile: lib/elixir/src/elixir.app.src erlang elixir
 
-erlang: $(PARSER)
-	$(Q) if [ ! -f $(APP) ]; then $(call CHECK_ERLANG_RELEASE); fi
-	$(Q) cd lib/elixir && mkdir -p ebin && $(ERL_MAKE)
+lib/elixir/src/elixir.app.src: src/elixir.app.src
+	$(Q) $(call CHECK_ERLANG_RELEASE)
+	$(Q) rm -rf lib/elixir/src/elixir.app.src
+	$(Q) echo "%% This file is automatically generated from <project_root>/src/elixir.app.src" \
+	                             >lib/elixir/src/elixir.app.src
+	$(Q) cat src/elixir.app.src >>lib/elixir/src/elixir.app.src
 
-$(PARSER): lib/elixir/src/elixir_parser.yrl
-	$(Q) erlc -o $@ +'{verbose,true}' +'{report,true}' $<
+erlang:
+	$(Q) cd lib/elixir && $(REBAR) compile
 
-# Since Mix depends on EEx and EEx depends on Mix,
-# we first compile EEx without the .app file,
-# then Mix, and then compile EEx fully
+# Since Mix depends on EEx and EEx depends on
+# Mix, we first compile EEx without the .app
+# file, then mix and then compile EEx fully
 elixir: stdlib lib/eex/ebin/Elixir.EEx.beam mix ex_unit logger eex iex
 
 stdlib: $(KERNEL) VERSION
 $(KERNEL): lib/elixir/lib/*.ex lib/elixir/lib/*/*.ex lib/elixir/lib/*/*/*.ex
-	$(Q) if [ ! -f $(KERNEL) ]; then \
-		echo "==> bootstrap (compile)"; \
-		$(ERL) -s elixir_compiler bootstrap -s erlang halt; \
+	$(Q) if [ ! -f $(KERNEL) ]; then                  \
+		echo "==> bootstrap (compile)";                 \
+		$(ERL) -s elixir_compiler core -s erlang halt;  \
 	fi
-	$(Q) $(MAKE) unicode
 	@ echo "==> elixir (compile)";
+	$(Q) cd lib/elixir && ../../$(ELIXIRC) "lib/kernel.ex" -o ebin;
 	$(Q) cd lib/elixir && ../../$(ELIXIRC) "lib/**/*.ex" -o ebin;
-	$(Q) $(MAKE) app
-
-app: $(APP)
-$(APP): lib/elixir/src/elixir.app.src lib/elixir/ebin VERSION $(GENERATE_APP)
-	$(Q) $(GENERATE_APP) $< $@ $(VERSION)
+	$(Q) $(MAKE) unicode
+	$(Q) rm -rf lib/elixir/ebin/elixir.app
+	$(Q) cd lib/elixir && $(REBAR) compile
 
 unicode: $(UNICODE)
 $(UNICODE): lib/elixir/unicode/*
 	@ echo "==> unicode (compile)";
-	$(Q) $(ELIXIRC) lib/elixir/unicode/unicode.ex -o lib/elixir/ebin;
-	$(Q) $(ELIXIRC) lib/elixir/unicode/tokenizer.ex -o lib/elixir/ebin;
+	$(Q) cd lib/elixir && ../../$(ELIXIRC) unicode/unicode.ex -o ebin;
 
 $(eval $(call APP_TEMPLATE,ex_unit,ExUnit))
 $(eval $(call APP_TEMPLATE,logger,Logger))
@@ -116,158 +100,98 @@ $(eval $(call APP_TEMPLATE,iex,IEx))
 install: compile
 	@ echo "==> elixir (install)"
 	$(Q) for dir in lib/*; do \
-		rm -rf $(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin; \
+		rm -Rf $(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin; \
 		$(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin"; \
 		$(INSTALL_DATA) $$dir/ebin/* "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/$$dir/ebin"; \
 	done
 	$(Q) $(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/bin"
 	$(Q) $(INSTALL_PROGRAM) $(filter-out %.ps1, $(filter-out %.bat, $(wildcard bin/*))) "$(DESTDIR)$(PREFIX)/$(LIBDIR)/elixir/bin"
 	$(Q) $(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/$(BINDIR)"
-	$(Q) for file in "$(DESTDIR)$(PREFIX)"/$(LIBDIR)/elixir/bin/*; do \
-		ln -sf "../$(LIBDIR)/elixir/bin/$${file##*/}" "$(DESTDIR)$(PREFIX)/$(BINDIR)/"; \
+	$(Q) for file in "$(DESTDIR)$(PREFIX)"/$(LIBDIR)/elixir/bin/* ; do \
+		ln -sf "../$(LIBDIR)/elixir/bin/$${file##*/}" "$(DESTDIR)$(PREFIX)/$(BINDIR)/" ; \
 	done
 	$(MAKE) install_man
 
-check_reproducible: compile
-	$(Q) echo "==> Checking for reproducible builds..."
-	$(Q) rm -rf lib/*/tmp/ebin_reproducible/
-	$(call WRITE_SOURCE_DATE_EPOCH)
-	$(Q) mkdir -p lib/elixir/tmp/ebin_reproducible/ \
-	              lib/eex/tmp/ebin_reproducible/ \
-	              lib/ex_unit/tmp/ebin_reproducible/ \
-	              lib/iex/tmp/ebin_reproducible/ \
-	              lib/logger/tmp/ebin_reproducible/ \
-	              lib/mix/tmp/ebin_reproducible/
-	$(Q) mv lib/elixir/ebin/* lib/elixir/tmp/ebin_reproducible/
-	$(Q) mv lib/eex/ebin/* lib/eex/tmp/ebin_reproducible/
-	$(Q) mv lib/ex_unit/ebin/* lib/ex_unit/tmp/ebin_reproducible/
-	$(Q) mv lib/iex/ebin/* lib/iex/tmp/ebin_reproducible/
-	$(Q) mv lib/logger/ebin/* lib/logger/tmp/ebin_reproducible/
-	$(Q) mv lib/mix/ebin/* lib/mix/tmp/ebin_reproducible/
-	SOURCE_DATE_EPOCH=$(call READ_SOURCE_DATE_EPOCH) $(MAKE) compile
-	$(Q) echo "Diffing..."
-	$(Q) bin/elixir lib/elixir/diff.exs lib/elixir/ebin/ lib/elixir/tmp/ebin_reproducible/
-	$(Q) bin/elixir lib/elixir/diff.exs lib/eex/ebin/ lib/eex/tmp/ebin_reproducible/
-	$(Q) bin/elixir lib/elixir/diff.exs lib/ex_unit/ebin/ lib/ex_unit/tmp/ebin_reproducible/
-	$(Q) bin/elixir lib/elixir/diff.exs lib/iex/ebin/ lib/iex/tmp/ebin_reproducible/
-	$(Q) bin/elixir lib/elixir/diff.exs lib/logger/ebin/ lib/logger/tmp/ebin_reproducible/
-	$(Q) bin/elixir lib/elixir/diff.exs lib/mix/ebin/ lib/mix/tmp/ebin_reproducible/
-	$(Q) echo "Builds are reproducible"
-
 clean:
+	cd lib/elixir && $(REBAR) clean
 	rm -rf ebin
 	rm -rf lib/*/ebin
-	rm -rf $(PARSER)
-	$(Q) $(MAKE) clean_residual_files
+	rm -rf lib/elixir/test/ebin
+	rm -rf lib/*/tmp
+	rm -rf lib/mix/test/fixtures/git_repo
+	rm -rf lib/mix/test/fixtures/deps_on_git_repo
+	rm -rf lib/mix/test/fixtures/git_rebar
+	rm -rf lib/elixir/src/elixir.app.src
+	$(MAKE) clean_man
 
-clean_elixir:
+clean_exbeam:
 	$(Q) rm -f lib/*/ebin/Elixir.*.beam
 
-clean_residual_files:
-	rm -rf lib/*/_build/
-	rm -rf lib/*/tmp/
-	rm -rf lib/elixir/test/ebin/
-	rm -rf lib/mix/test/fixtures/deps_on_git_repo/
-	rm -rf lib/mix/test/fixtures/git_rebar/
-	rm -rf lib/mix/test/fixtures/git_repo/
-	rm -rf lib/mix/test/fixtures/git_sparse_repo/
-	rm -f erl_crash.dump
-	$(Q) $(MAKE) clean_man
-
-#==> Documentation tasks
+#==> Create Documentation
 
 LOGO_PATH = $(shell test -f ../docs/logo.png && echo "--logo ../docs/logo.png")
-SOURCE_REF = $(shell tag="$(call GIT_TAG)" revision="$(call GIT_REVISION)"; echo "$${tag:-$$revision}")
+SOURCE_REF = $(shell tag="$(call GIT_TAG)" revision="$(call GIT_REVISION)"; echo "$${tag:-$$revision}\c")
 DOCS_FORMAT = html
-COMPILE_DOCS = CANONICAL=$(CANONICAL) bin/elixir ../ex_doc/bin/ex_doc "$(1)" "$(VERSION)" "lib/$(2)/ebin" --main "$(3)" --source-url "https://github.com/elixir-lang/elixir" --source-ref "$(call SOURCE_REF)" $(call LOGO_PATH) --output doc/$(2) --canonical "https://hexdocs.pm/$(2)/$(CANONICAL)" --homepage-url "https://elixir-lang.org/docs.html" --formatter "$(DOCS_FORMAT)" $(4)
+COMPILE_DOCS = bin/elixir ../ex_doc/bin/ex_doc "$(1)" "$(VERSION)" "lib/$(2)/ebin" -m "$(3)" -u "https://github.com/elixir-lang/elixir" --source-ref "$(call SOURCE_REF)" $(call LOGO_PATH) -o doc/$(2) -n https://hexdocs.pm/$(2)/$(CANONICAL) -p http://elixir-lang.org/docs.html -f "$(DOCS_FORMAT)" $(4)
 
 docs: compile ../ex_doc/bin/ex_doc docs_elixir docs_eex docs_mix docs_iex docs_ex_unit docs_logger
 
 docs_elixir: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (elixir)"
 	$(Q) rm -rf doc/elixir
-	$(call COMPILE_DOCS,Elixir,elixir,Kernel,--config "lib/elixir/docs.exs")
+	$(call COMPILE_DOCS,Elixir,elixir,Kernel,-e "lib/elixir/pages/Behaviours.md" -e "lib/elixir/pages/Guards.md" -e "lib/elixir/pages/Naming Conventions.md" -e "lib/elixir/pages/Operators.md" -e "lib/elixir/pages/Typespecs.md" -e "lib/elixir/pages/Writing Documentation.md")
 
 docs_eex: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (eex)"
 	$(Q) rm -rf doc/eex
-	$(call COMPILE_DOCS,EEx,eex,EEx,--config "lib/mix/docs.exs")
+	$(call COMPILE_DOCS,EEx,eex,EEx)
 
 docs_mix: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (mix)"
 	$(Q) rm -rf doc/mix
-	$(call COMPILE_DOCS,Mix,mix,Mix,--config "lib/mix/docs.exs")
+	$(call COMPILE_DOCS,Mix,mix,Mix)
 
 docs_iex: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (iex)"
 	$(Q) rm -rf doc/iex
-	$(call COMPILE_DOCS,IEx,iex,IEx,--config "lib/mix/docs.exs")
+	$(call COMPILE_DOCS,IEx,iex,IEx)
 
 docs_ex_unit: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (ex_unit)"
 	$(Q) rm -rf doc/ex_unit
-	$(call COMPILE_DOCS,ExUnit,ex_unit,ExUnit,--config "lib/mix/docs.exs")
+	$(call COMPILE_DOCS,ExUnit,ex_unit,ExUnit)
 
 docs_logger: compile ../ex_doc/bin/ex_doc
 	@ echo "==> ex_doc (logger)"
 	$(Q) rm -rf doc/logger
-	$(call COMPILE_DOCS,Logger,logger,Logger,--config "lib/mix/docs.exs")
+	$(call COMPILE_DOCS,Logger,logger,Logger)
 
 ../ex_doc/bin/ex_doc:
 	@ echo "ex_doc is not found in ../ex_doc as expected. See README for more information."
 	@ false
 
-#==> Zip tasks
+#==> Zips
 
 Docs.zip: docs
-	rm -f Docs-v$(VERSION).zip
+	rm -rf Docs-v$(VERSION).zip
 	zip -9 -r Docs-v$(VERSION).zip CHANGELOG.md doc NOTICE LICENSE README.md
 	@ echo "Docs file created $(CURDIR)/Docs-v$(VERSION).zip"
 
 Precompiled.zip: build_man compile
-	rm -f Precompiled-v$(VERSION).zip
-	zip -9 -r Precompiled-v$(VERSION).zip bin CHANGELOG.md lib/*/ebin lib/*/lib LICENSE man NOTICE README.md VERSION
+	rm -rf Precompiled-v$(VERSION).zip
+	zip -9 -r Precompiled-v$(VERSION).zip bin CHANGELOG.md lib/*/ebin LICENSE man NOTICE README.md VERSION
 	@ echo "Precompiled file created $(CURDIR)/Precompiled-v$(VERSION).zip"
 
 zips: Precompiled.zip Docs.zip
-	@ echo ""
-	@ echo "### Checksums"
-	@ echo ""
-	@ shasum -a 1 < Precompiled-v$(VERSION).zip | sed -e "s/-//" | xargs echo "  * Precompiled.zip SHA1:"
-	@ shasum -a 512 < Precompiled-v$(VERSION).zip | sed -e "s/-//" | xargs echo "  * Precompiled.zip SHA512:"
-	@ shasum -a 1 < Docs-v$(VERSION).zip | sed -e "s/-//" | xargs echo "  * Docs.zip SHA1:"
-	@ shasum -a 512 < Docs-v$(VERSION).zip | sed -e "s/-//" | xargs echo "  * Docs.zip SHA512:"
-	@ echo ""
 
-#==> Test tasks
+#==> Tests tasks
 
-# If you modify this task, please update .cirrus.yml accordingly
-test: test_formatted test_erlang test_elixir
-
-test_windows: test test_taskkill
-
-test_taskkill:
-	taskkill //IM erl.exe //F //T //FI "MEMUSAGE gt 0"
-	taskkill //IM epmd.exe //F //T //FI "MEMUSAGE gt 0"
+test: test_erlang test_elixir
 
 TEST_ERL = lib/elixir/test/erlang
 TEST_EBIN = lib/elixir/test/ebin
 TEST_ERLS = $(addprefix $(TEST_EBIN)/, $(addsuffix .beam, $(basename $(notdir $(wildcard $(TEST_ERL)/*.erl)))))
 
-define FORMAT
-	$(Q) if [ "$(OS)" = "Windows_NT" ]; then \
-		cmd //C call ./bin/mix.bat format $(1); \
-	else \
-		bin/elixir bin/mix format $(1); \
-	fi
-endef
-
-format: compile
-	$(call FORMAT)
-
-test_formatted: compile
-	$(call FORMAT,--check-formatted)
-
 test_erlang: compile $(TEST_ERLS)
 	@ echo "==> elixir (eunit)"
 	$(Q) $(ERL) -pa $(TEST_EBIN) -s test_helper test;
@@ -277,15 +201,15 @@ $(TEST_EBIN)/%.beam: $(TEST_ERL)/%.erl
 	$(Q) mkdir -p $(TEST_EBIN)
 	$(Q) $(ERLC) -o $(TEST_EBIN) $<
 
-test_elixir: test_stdlib test_ex_unit test_logger test_eex test_iex test_mix
+test_elixir: test_stdlib test_ex_unit test_logger test_mix test_eex test_iex
 
 test_stdlib: compile
-	@ echo "==> elixir (ex_unit)"
+	@ echo "==> elixir (exunit)"
 	$(Q) exec epmd & exit
 	$(Q) if [ "$(OS)" = "Windows_NT" ]; then \
-		cd lib/elixir && cmd //C call ../../bin/elixir.bat -r "test/elixir/test_helper.exs" -pr "test/elixir/**/$(TEST_FILES)"; \
+		cd lib/elixir && cmd //C call ../../bin/elixir.bat -r "test/elixir/test_helper.exs" -pr "test/elixir/**/*_test.exs"; \
 	else \
-		cd lib/elixir && ../../bin/elixir -r "test/elixir/test_helper.exs" -pr "test/elixir/**/$(TEST_FILES)"; \
+		cd lib/elixir && ../../bin/elixir -r "test/elixir/test_helper.exs" -pr "test/elixir/**/*_test.exs"; \
 	fi
 
 #==> Dialyzer tasks
@@ -295,7 +219,7 @@ PLT = .elixir.plt
 
 $(PLT):
 	@ echo "==> Building PLT with Elixir's dependencies..."
-	$(Q) dialyzer --output_plt $(PLT) --build_plt --apps erts kernel stdlib compiler syntax_tools parsetools tools ssl inets crypto runtime_tools ftp tftp mnesia public_key asn1 hipe sasl
+	$(Q) dialyzer --output_plt $(PLT) --build_plt --apps erts kernel stdlib compiler syntax_tools parsetools tools ssl inets
 
 clean_plt:
 	$(Q) rm -f $(PLT)
@@ -304,7 +228,7 @@ build_plt: clean_plt $(PLT)
 
 dialyze: compile $(PLT)
 	@ echo "==> Dialyzing Elixir..."
-	$(Q) dialyzer -pa lib/elixir/ebin --plt $(PLT) $(DIALYZER_OPTS) lib/*/ebin
+	$(Q) dialyzer --plt $(PLT) $(DIALYZER_OPTS) lib/*/ebin
 
 #==> Man page tasks
 
@@ -312,26 +236,24 @@ build_man: man/iex.1 man/elixir.1
 
 man/iex.1:
 	$(Q) cp man/iex.1.in man/iex.1
-	$(Q) sed -i.bak "/{COMMON}/r man/common" man/iex.1
+	$(Q) sed -i.bak "/{COMMON}/r common" man/iex.1
 	$(Q) sed -i.bak "/{COMMON}/d" man/iex.1
-	$(Q) rm -f man/iex.1.bak
+	$(Q) rm man/iex.1.bak
 
 man/elixir.1:
 	$(Q) cp man/elixir.1.in man/elixir.1
-	$(Q) sed -i.bak "/{COMMON}/r man/common" man/elixir.1
+	$(Q) sed -i.bak "/{COMMON}/r common" man/elixir.1
 	$(Q) sed -i.bak "/{COMMON}/d" man/elixir.1
-	$(Q) rm -f man/elixir.1.bak
+	$(Q) rm man/elixir.1.bak
 
 clean_man:
 	rm -f man/elixir.1
-	rm -f man/elixir.1.bak
 	rm -f man/iex.1
-	rm -f man/iex.1.bak
 
 install_man: build_man
-	$(Q) mkdir -p $(DESTDIR)$(MAN_PREFIX)/man1
-	$(Q) $(INSTALL_DATA) man/elixir.1  $(DESTDIR)$(MAN_PREFIX)/man1
-	$(Q) $(INSTALL_DATA) man/elixirc.1 $(DESTDIR)$(MAN_PREFIX)/man1
-	$(Q) $(INSTALL_DATA) man/iex.1     $(DESTDIR)$(MAN_PREFIX)/man1
-	$(Q) $(INSTALL_DATA) man/mix.1     $(DESTDIR)$(MAN_PREFIX)/man1
+	$(Q) mkdir -p $(DESTDIR)$(SHARE_PREFIX)/man/man1
+	$(Q) $(INSTALL_DATA) man/elixir.1  $(DESTDIR)$(SHARE_PREFIX)/man/man1
+	$(Q) $(INSTALL_DATA) man/elixirc.1 $(DESTDIR)$(SHARE_PREFIX)/man/man1
+	$(Q) $(INSTALL_DATA) man/iex.1     $(DESTDIR)$(SHARE_PREFIX)/man/man1
+	$(Q) $(INSTALL_DATA) man/mix.1     $(DESTDIR)$(SHARE_PREFIX)/man/man1
 	$(MAKE) clean_man

NOTICE

@@ -1,7 +1,9 @@
 LEGAL NOTICE INFORMATION
 ------------------------
 
-All the files in this distribution are copyright to the terms below.
+All the files in this distribution are copyright (c) 2012 Plataformatec
+covered under Elixir's license (see the file LICENSE) except the cases
+below.
 
 == lib/elixir/src/elixir_parser.erl (generated by build scripts)
 
@@ -11,24 +13,7 @@ Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 
-    https://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-
-== All other files
-
-Copyright 2012 Plataformatec
-Copyright 2021 The Elixir Team
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-   https://www.apache.org/licenses/LICENSE-2.0
+    http://www.apache.org/licenses/LICENSE-2.0
 
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,

README.md

@@ -1,81 +1,14 @@
-<img src="https://github.com/elixir-lang/elixir-lang.github.com/raw/master/images/logo/logo.png" width="200" alt="Elixir">
-
-[![CI](https://github.com/elixir-lang/elixir/workflows/CI/badge.svg?branch=master)](https://github.com/elixir-lang/elixir/actions?query=branch%3Amaster+workflow%3ACI) [![Build status](https://api.cirrus-ci.com/github/elixir-lang/elixir.svg?branch=master)](https://cirrus-ci.com/github/elixir-lang/elixir)
-
-Elixir is a dynamic, functional language designed for building scalable
-and maintainable applications.
+![Elixir](https://github.com/elixir-lang/elixir-lang.github.com/raw/master/images/logo/logo.png)
+=========
+[![Build Status](https://secure.travis-ci.org/elixir-lang/elixir.svg?branch=master
+"Build Status")](https://travis-ci.org/elixir-lang/elixir)
 
 For more about Elixir, installation and documentation,
-[check Elixir's website](https://elixir-lang.org/).
-
-## Policies
-
-New releases are announced in the [announcement mailing list][8].
-You can subscribe by sending an email to elixir-lang-ann+subscribe@googlegroups.com
-and replying to the confirmation email.
-
-All security releases [will be tagged with `[security]`][10]. For more
-information, please read our [Security Policy][9].
-
-All interactions in our official communication channels follow our
-[Code of Conduct][1].
-
-## Bug reports
-
-For reporting bugs, [visit our issue tracker][2] and follow the steps
-for reporting a new issue. **Please disclose security vulnerabilities
-privately at elixir-security@googlegroups.com**.
-
-## Issues tracker management
-
-All currently open bugs related to the Elixir repository are listed
-in the issues tracker. The Elixir team uses the issues tracker to focus
-on *actionable items*, including planned enhancements in the short- and
-medium-term. We also do our best to label entries for clarity and to ease
-collaboration.
-
-Our *actionable item policy* has some important consequences, such as:
-
-  * Proposing new features as well as request for support, help, and
-    guidance must be done in their own spaces, detailed next.
-
-  * Issues where we have identified to be outside of Elixir scope,
-    such as a bug upstream, will be closed (and requested to be moved
-    elsewhere if appropriate).
-
-  * We actively close unrelated and non-actionable issues to keep the
-    issues tracker tidy. However, we may get things wrong from time to
-    time, so we are glad to revisit issues and reopen if necessary.
-
-Keep the tone positive and be kind! For more information, see the
-[Code of Conduct][1].
-
-### Proposing new features
-
-For proposing new features, please start a discussion in the
-[Elixir Core mailing list][3]. Keep in mind that it is your responsibility
-to argue and explain why a feature is useful and how it will impact the
-codebase and the community.
-
-Once a proposal is accepted, it will be added to [the issue tracker][2].
-Features and bug fixes that have already been merged and will be included
-in the next release are then "closed" and added to the [changelog][7].
-
-### Discussions, support, and help
-
-For general discussions, support, and help, please use many of the community
-spaces [listed on the sidebar of the Elixir website](https://elixir-lang.org/),
-such as forums, chat platforms, etc, where the wider community will be available
-to help you.
+[check Elixir's website](http://elixir-lang.org/).
 
 ## Compiling from source
 
-For the many different ways to install Elixir,
-[see our installation instructions on the website](https://elixir-lang.org/install.html).
-However, if you want to contribute to Elixir, you will need to compile from source.
-
-First, [install Erlang](https://elixir-lang.org/install.html#installing-erlang).
-After that, clone this repository to your machine, compile and test it:
+To run Elixir from source, clone this repository to your machine, compile and test it:
 
 ```sh
 git clone https://github.com/elixir-lang/elixir.git
@@ -87,37 +20,51 @@ make clean test
 [this article includes important notes for compiling Elixir from source
 on Windows](https://github.com/elixir-lang/elixir/wiki/Windows).
 
-In case you want to use this Elixir version as your system version,
-you need to add the `bin` directory to [your PATH environment variable](https://elixir-lang.org/install.html#setting-path-environment-variable).
-
 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 18.0 or later). You can check your Erlang version
+by calling `erl` in the command line. You will see some information as follows:
+
+    Erlang/OTP 18 [erts-7.0] [source] [smp:2:2] [async-threads:10] [hipe] [kernel-poll:false]
+
+If you have properly set up your dependencies and tests still fail,
+you may want to open up a bug report, as explained next.
+
+## Bug reports
+
+For reporting bugs, [visit our issues tracker][2] and follow the steps
+for reporting a new issue. Please disclose security vulnerabilities
+privately at elixir-security@googlegroups.com.
+
 ## Contributing
 
-We welcome everyone to contribute to Elixir. To do so, there are a few
-things you need to know about the code. First, Elixir code is divided
-in applications inside the `lib` folder:
+We welcome everyone to contribute to Elixir and help us tackle existing issues!
+To do so, there are a few things you need to know about the code. First, Elixir
+code is divided in applications inside the `lib` folder:
 
-* `elixir` - Elixir's kernel and standard library
+* `elixir` - Contains Elixir's kernel and stdlib
 
-* `eex` - EEx is the template engine that allows you to embed Elixir
+* `eex` - Template engine that allows you to embed Elixir
 
-* `ex_unit` - ExUnit is a simple test framework that ships with Elixir
+* `ex_unit` - Simple test framework that ships with Elixir
 
-* `iex` - IEx stands for Interactive Elixir: Elixir's interactive shell
+* `iex` - IEx, Elixir's interactive shell
 
-* `logger` - Logger is the built-in logger
+* `logger` - The built-in logger
 
-* `mix` - Mix is Elixir's build tool
+* `mix` - Elixir's build tool
 
 You can run all tests in the root directory with `make test` and you can
-also run tests for a specific framework `make test_#{APPLICATION}`, for example,
-`make test_ex_unit`. If you just changed something in the Elixir's standard
-library, you can run only that portion through `make test_stdlib`.
+also run tests for a specific framework `make test_#{NAME}`, for example,
+`make test_ex_unit`.
 
-If you are changing just one file, you can choose to compile and run tests only
+In case you are changing a single file, you can compile and run tests only
 for that particular file for fast development cycles. For example, if you
 are changing the String module, you can compile it and run its tests as:
 
@@ -126,36 +73,28 @@ bin/elixirc lib/elixir/lib/string.ex -o lib/elixir/ebin
 bin/elixir lib/elixir/test/elixir/string_test.exs
 ```
 
-To recompile (including Erlang modules):
-
-```sh
-make compile
-```
-
-After your changes are done, please remember to run `make format` to guarantee
-all files are properly formatted and then run the full suite with
+After your changes are done, please remember to run the full suite with
 `make test`.
 
-If your contribution fails during the bootstrapping of the language,
-you can rebuild the language from scratch with:
-
-```sh
-make clean_elixir compile
-```
-
-Similarly, if you can't get Elixir to compile or the tests to pass after
-updating an existing checkout, run `make clean compile`. You can check
-[the official build status](https://github.com/elixir-lang/elixir/actions/workflows/ci.yml).
-More tasks can be found by reading the [Makefile](Makefile).
+From time to time, your tests may fail in an existing Elixir checkout and
+may require a clean start by running `make clean compile`. You can always
+check [the official build status on Travis-CI](https://travis-ci.org/elixir-lang/elixir).
 
 With tests running and passing, you are ready to contribute to Elixir and
 [send a pull request](https://help.github.com/articles/using-pull-requests/).
 We have saved some excellent pull requests we have received in the past in
 case you are looking for some examples:
 
-* [Implement Enum.member? - Pull request](https://github.com/elixir-lang/elixir/pull/992)
-* [Add String.valid? - Pull request](https://github.com/elixir-lang/elixir/pull/1058)
-* [Implement capture_io for ExUnit - Pull request](https://github.com/elixir-lang/elixir/pull/1059)
+* [Implement Enum.member? – Pull Request](https://github.com/elixir-lang/elixir/pull/992)
+* [Add String.valid? – Pull Request](https://github.com/elixir-lang/elixir/pull/1058)
+* [Implement capture_io for ExUnit – Pull Request](https://github.com/elixir-lang/elixir/pull/1059)
+
+We usually keep a list of enhancements and bugs [in the issue tracker][2].
+For proposing new features, please start a discussion in the
+[Elixir Core mailing list][3]. Keep in mind that it is your responsibility
+to argue and explain why a feature is useful and how it will impact the
+codebase and the community. Finally, remember all interactions in our official
+spaces follow our [Code of Conduct][7].
 
 ### Reviewing changes
 
@@ -163,23 +102,15 @@ Once a pull request is sent, the Elixir team will review your changes.
 We outline our process below to clarify the roles of everyone involved.
 
 All pull requests must be approved by two committers before being merged into
-the repository. If any changes are necessary, the team will leave appropriate
-comments requesting changes to the code. Unfortunately we cannot guarantee a
-pull request will be merged, even when modifications are requested, as the Elixir
-team will re-evaluate the contribution as it changes.
-
-Committers may also push style changes directly to your branch. If you would
-rather manage all changes yourself, you can disable "Allow edits from maintainers"
-feature when submitting your pull request.
+the repository. In case any changes are necessary, the team will leave
+appropriate comments requesting changes to the code.
 
 The Elixir team may optionally assign someone to review a pull request.
-If someone is assigned, they must explicitly approve the code before
+In case someone is assigned, they must explicitly approve the code before
 another team member can merge it.
 
-When the review finishes, your pull request will be squashed and merged
-into the repository. If you have carefully organized your commits and
-believe they should be merged without squashing, please mention it in
-a comment.
+When review is completed, your pull request will be squashed and merged
+into the repository.
 
 ## Building documentation
 
@@ -190,45 +121,35 @@ to be installed and built alongside Elixir:
 # After cloning and compiling Elixir, in its parent directory:
 git clone git://github.com/elixir-lang/ex_doc.git
 cd ex_doc && ../elixir/bin/mix do deps.get, compile
+cd ../elixir && make docs
 ```
 
-Now go back to Elixir's root directory and run:
-
-```sh
-make docs                  # to generate HTML pages
-make docs DOCS_FORMAT=epub # to generate EPUB documents
-```
-
-This will produce documentation sets for `elixir`, `eex`, `ex_unit`, `iex`, `logger`,
-and `mix` under the `doc` directory. If you are planning to contribute documentation,
-[please check our best practices for writing documentation](https://hexdocs.pm/elixir/writing-documentation.html).
+This will produce documentation sets for `elixir`, `mix`, etc., under
+the `doc` directory. If you are planning to contribute documentation,
+[please check our best practices for writing documentation](http://elixir-lang.org/docs/stable/elixir/writing-documentation.html).
 
 ## Development links
 
+  * [Elixir Website][1]
   * [Elixir Documentation][6]
   * [Elixir Core Mailing list (development)][3]
-  * [Announcement mailing list][8]
-  * [Code of Conduct][1]
-  * [Issue tracker][2]
-  * [Changelog][7]
-  * [Security Policy][9]
-  * **[#elixir][4]** on [Libera.Chat][5] IRC
+  * [Issues tracker][2]
+  * [Code of Conduct][7]
+  * **[#elixir-lang][4]** on [Freenode][5] IRC
 
-  [1]: CODE_OF_CONDUCT.md
+  [1]: http://elixir-lang.org
   [2]: https://github.com/elixir-lang/elixir/issues
   [3]: https://groups.google.com/group/elixir-lang-core
-  [4]: https://web.libera.chat/#elixir
-  [5]: https://libera.chat
-  [6]: https://elixir-lang.org/docs.html
-  [7]: CHANGELOG.md
-  [8]: https://groups.google.com/group/elixir-lang-ann
-  [9]: SECURITY.md
-  [10]: https://groups.google.com/forum/#!searchin/elixir-lang-ann/%5Bsecurity%5D%7Csort:date
+  [4]: https://webchat.freenode.net/?channels=#elixir-lang
+  [5]: http://www.freenode.net
+  [6]: http://elixir-lang.org/docs.html
+  [7]: CODE_OF_CONDUCT.md
 
 ## License
 
-"Elixir" and the Elixir logo are registered trademarks of The Elixir Team.
+"Elixir" and the Elixir logo are copyright (c) 2012 Plataformatec.
 
-Elixir source code is released under Apache License 2.0.
+Elixir source code is released under Apache 2 License.
 
-Check [NOTICE](NOTICE) and [LICENSE](LICENSE) files for more information.
+Check [NOTICE](NOTICE) and [LICENSE](LICENSE) files for more
+information.

RELEASE.md

@@ -1,45 +1,43 @@
 # Release process
 
-## Shipping a new version
+## All releases
+
+This document simply outlines the release process:
 
 1. Ensure you are running on the oldest supported Erlang version
 
-2. Update version in /VERSION, bin/elixir and bin/elixir.bat
+2. Remove all `-dev` extension from versions (see below for all files)
 
-3. Ensure /CHANGELOG.md is updated, versioned and add the current date
+3. Ensure CHANGELOG is updated and add current date
 
-4. Update "Compatibility and Deprecations" if a new OTP version is supported
+4. Commit changes above with title "Release vVERSION" and generate new tag
 
-5. Commit changes above with title "Release vVERSION" and generate a new tag
+5. Run `make clean test` to ensure all tests pass from scratch and the CI is green
 
-6. Run `make clean test` to ensure all tests pass from scratch and the CI is green
+6. Recompile an existing project (for example, Ecto) to ensure manifests can be upgraded
 
-7. Recompile an existing project (for example, Ecto) to ensure manifests can be upgraded
+7. Push branch and the new tag
 
-8. Push branch and the new tag
+8. If a new `vMAJOR.MINOR`, create a new branch "vMAJOR.MINOR" and set `CANONICAL=` in Makefile before building docs
 
-9. Publish new zips with `make zips`, upload `Precompiled.zip` and `Docs.zip` to GitHub Releases, and include SHAs+CHANGELOG
+9. Publish new zips with `make zips`, upload `Precompiled.zip` and `Docs.zip` to GitHub Releases
 
-10. Add the release to `elixir.csv` (all releases), update `erlang.csv` to the precompiled OTP version, and `_data/elixir-versions.yml` (except for RCs) files in `elixir-lang/elixir-lang.github.com`
+10. Add the release to `elixir.csv` and `_data/elixir-versions.yml` files in `elixir-lang/elixir-lang.github.com`
 
-11. Send an e-mail to elixir-lang-ann@googlegroups.com with title "Elixir vVERSION released". The body should be a link to the Release page on GitHub and the checksums. If it is a security release, prefix the title with the `[security]` tag
+11. After a new `vMAJOR.MINOR`, move back to master, bump versions, start new CHANGELOG, add `-dev` back and commit "Start vMAJOR.MINOR+1"
 
-## Creating a new vMAJOR.MINOR branch
+## Places where version is mentioned
 
-### In the new branch
+* VERSION
+* CHANGELOG.md
+* src/elixir.app.src (not lib/elixir/src/elixir.app.src)
 
-1. Set `CANONICAL=` in /Makefile
+## Deprecation policy
 
-2. Update tables in /SECURITY.md and "Compatibility and Deprecations"
+Elixir deprecations happens in 3 steps:
 
-3. Commit "Branch out vMAJOR.MINOR"
+  1. The feature is soft-deprecated. It means both CHANGELOG and documentation must list the feature as deprecated but no warning is effectively emitted by running the code. There is no requirement to soft-deprecate a feature.
 
-### Back in master
+  2. The feature is effectively deprecated by emitting warnings on usage. In order to deprecate a feature, the proposed alternative MUST exist for AT LEAST two versions. For example, `Enum.uniq/2` was soft-deprecated in favor of `Enum.uniq_by/2` in Elixir v1.1. This means a deprecation warning may only be emitted by Elixir v1.3 or later.
 
-1. Bump /VERSION file, bin/elixir and bin/elixir.bat
-
-2. Start new /CHANGELOG.md
-
-3. Update tables in /SECURITY.md in "Compatibility and Deprecations"
-
-4. Commit "Start vMAJOR.MINOR+1"
+  3. The feature is removed. This can only happen on major releases. This means deprecated features in Elixir v1.x shall only be removed by Elixir v2.x.

SECURITY.md

@@ -1,23 +0,0 @@
-# Security Policy
-
-## Supported versions
-
-Elixir applies bug fixes only to the latest minor branch. Security patches are available for the last 5 minor branches:
-
-Elixir version | Support
-:------------- | :-----------------------------
-1.13           | Bug fixes and security patches
-1.12           | Security patches only
-1.11           | Security patches only
-1.10           | Security patches only
-1.9            | Security patches only
-
-## Announcements
-
-New releases are announced in the read-only [announcements mailing list](https://groups.google.com/group/elixir-lang-ann). You can subscribe by sending an email to elixir-lang-ann+subscribe@googlegroups.com and replying to the confirmation email.
-
-All security releases [will be tagged with `[security]`](https://groups.google.com/forum/#!searchin/elixir-lang-ann/%5Bsecurity%5D%7Csort:date).
-
-## Reporting a vulnerability
-
-Please disclose security vulnerabilities privately at elixir-security@googlegroups.com

VERSION

@@ -1 +1 @@
-1.13.3
+1.4.3

bin/elixir

@@ -1,62 +1,30 @@
 #!/bin/sh
-set -e
+if [ $# -eq 0 ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
+  echo "Usage: `basename $0` [options] [.exs file] [data]
 
-ELIXIR_VERSION=1.13.3
+  -v                          Prints version and exits
+  -e COMMAND                  Evaluates the given command (*)
+  -r FILE                     Requires the given files/patterns (*)
+  -S SCRIPT                   Finds and executes the given script in PATH
+  -pr FILE                    Requires the given files/patterns in parallel (*)
+  -pa PATH                    Prepends the given path to Erlang code path (*)
+  -pz PATH                    Appends the given path to Erlang code path (*)
 
-if [ $# -eq 0 ] || { [ $# -eq 1 ] && { [ "$1" = "--help" ] || [ "$1" = "-h" ]; }; }; then
-  cat <<USAGE >&2
-Usage: $(basename "$0") [options] [.exs file] [data]
+  --app APP                   Starts the given app and its dependencies (*)
+  --cookie COOKIE             Sets a cookie for this distributed node
+  --detached                  Starts the Erlang VM detached from console
+  --erl SWITCHES              Switches to be passed down to Erlang (*)
+  --hidden                    Makes a hidden node
+  --logger-otp-reports BOOL   Enables or disables OTP reporting
+  --logger-sasl-reports BOOL  Enables or disables SASL reporting
+  --name NAME                 Makes and assigns a name to the distributed node
+  --no-halt                   Does not halt the Erlang VM after execution
+  --sname NAME                Makes and assigns a short name to the distributed node
+  --werl                      Uses Erlang's Windows shell GUI (Windows only)
 
-## General options
-
-  -e "COMMAND"                 Evaluates the given command (*)
-  -h, --help                   Prints this message (standalone)
-  -r "FILE"                    Requires the given files/patterns (*)
-  -S SCRIPT                    Finds and executes the given script in \$PATH
-  -pr "FILE"                   Requires the given files/patterns in parallel (*)
-  -pa "PATH"                   Prepends the given path to Erlang code path (*)
-  -pz "PATH"                   Appends the given path to Erlang code path (*)
-  -v, --version                Prints Erlang/OTP and Elixir versions (standalone)
-
-  --app APP                    Starts the given app and its dependencies (*)
-  --erl "SWITCHES"             Switches to be passed down to Erlang (*)
-  --eval "COMMAND"             Evaluates the given command, same as -e (*)
-  --logger-otp-reports BOOL    Enables or disables OTP reporting
-  --logger-sasl-reports BOOL   Enables or disables SASL reporting
-  --no-halt                    Does not halt the Erlang VM after execution
-  --short-version              Prints Elixir version (standalone)
-  --werl                       Uses Erlang's Windows shell GUI (Windows only)
-
-Options given after the .exs file or -- are passed down to the executed code.
-Options can be passed to the Erlang runtime using \$ELIXIR_ERL_OPTIONS or --erl.
-
-## Distribution options
-
-The following options are related to node distribution.
-
-  --cookie COOKIE              Sets a cookie for this distributed node
-  --hidden                     Makes a hidden node
-  --name NAME                  Makes and assigns a name to the distributed node
-  --rpc-eval NODE "COMMAND"    Evaluates the given command on the given remote node (*)
-  --sname NAME                 Makes and assigns a short name to the distributed node
-
-## Release options
-
-The following options are generally used under releases.
-
-  --boot "FILE"                Uses the given FILE.boot to start the system
-  --boot-var VAR "VALUE"       Makes \$VAR available as VALUE to FILE.boot (*)
-  --erl-config "FILE"          Loads configuration in FILE.config written in Erlang (*)
-  --pipe-to "PIPEDIR" "LOGDIR" Starts the Erlang VM as a named PIPEDIR and LOGDIR
-  --vm-args "FILE"             Passes the contents in file as arguments to the VM
-
---pipe-to starts Elixir detached from console (Unix-like only).
-It will attempt to create PIPEDIR and LOGDIR if they don't exist.
-See run_erl to learn more. To reattach, run: to_erl PIPEDIR.
-
-** Options marked with (*) can be given more than once.
-** Standalone options can't be combined with other options.
-USAGE
+** Options marked with (*) can be given more than once
+** Options given after the .exs file or -- are passed down to the executed code
+** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS or --erl" >&2
   exit 1
 fi
 
@@ -66,147 +34,70 @@ readlink_f () {
   if [ -h "$filename" ]; then
     readlink_f "$(readlink "$filename")"
   else
-    echo "$(pwd -P)/$filename"
+    echo "`pwd -P`/$filename"
   fi
 }
 
-if [ $# -eq 1 ] && [ "$1" = "--short-version" ]; then
-  echo "$ELIXIR_VERSION"
-  exit 0
-fi
-
-# Stores static Erlang arguments and --erl (which is passed as is)
-ERL=""
-
-# Stores erl arguments preserving spaces/quotes (mimics an array)
-erl_set () {
-  eval "E${E}=\$1"
-  E=$((E + 1))
-}
-
-# Checks if a string starts with prefix. Usage: starts_with "$STRING" "$PREFIX"
-starts_with () {
-  case $1 in
-    "$2"*) true;;
-    *) false;;
-  esac
-}
-
-ERL_EXEC="erl"
 MODE="elixir"
+ERL_EXEC="erl"
+ERL=""
 I=1
-E=0
-LENGTH=$#
-set -- "$@" -extra
 
-while [ $I -le $LENGTH ]; do
+while [ $I -le $# ]; do
   S=1
-  case "$1" in
+  eval "PEEK=\${$I}"
+  case "$PEEK" in
     +iex)
-        set -- "$@" "$1"
         MODE="iex"
         ;;
     +elixirc)
-        set -- "$@" "$1"
         MODE="elixirc"
         ;;
-    -v|--no-halt)
-        set -- "$@" "$1"
+    -v|--compile|--no-halt)
         ;;
-    -e|-r|-pr|-pa|-pz|--app|--eval|--remsh|--dot-iex)
+    -e|-r|-pr|-pa|-pz|--remsh|--app)
         S=2
-        set -- "$@" "$1" "$2"
         ;;
-    --rpc-eval)
-        S=3
-        set -- "$@" "$1" "$2" "$3"
+    --detached|--hidden)
+        ERL="$ERL `echo $PEEK | cut -c 2-`"
         ;;
-    --detached)
-        echo "warning: the --detached option is deprecated" >&2
-        ERL="$ERL -detached"
+    --cookie)
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        ERL="$ERL -setcookie "$VAL""
         ;;
-    --hidden)
-        ERL="$ERL -hidden"
+    --sname|--name)
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        ERL="$ERL `echo $PEEK | cut -c 2-` "$VAL""
         ;;
     --logger-otp-reports)
-        S=2
-        if [ "$2" = 'true' ] || [ "$2" = 'false' ]; then
-          ERL="$ERL -logger handle_otp_reports $2"
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        if [ "$VAL" == 'true' ] || [ "$VAL" == 'false' ]; then
+            ERL="$ERL -logger handle_otp_reports "$VAL""
         fi
         ;;
     --logger-sasl-reports)
-        S=2
-        if [ "$2" = 'true' ] || [ "$2" = 'false' ]; then
-          ERL="$ERL -logger handle_sasl_reports $2"
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        if [ "$VAL" == 'true' ] || [ "$VAL" == 'false' ]; then
+            ERL="$ERL -logger handle_sasl_reports "$VAL""
         fi
         ;;
     --erl)
-        S=2
-        ERL="$ERL $2"
-        ;;
-    --cookie)
-        S=2
-        erl_set "-setcookie"
-        erl_set "$2"
-        ;;
-    --sname|--name)
-        S=2
-        erl_set "$(echo "$1" | cut -c 2-)"
-        erl_set "$2"
-        ;;
-    --erl-config)
-        S=2
-        erl_set "-config"
-        erl_set "$2"
-        ;;
-    --vm-args)
-        S=2
-        erl_set "-args_file"
-        erl_set "$2"
-        ;;
-    --boot)
-        S=2
-        erl_set "-boot"
-        erl_set "$2"
-        ;;
-    --boot-var)
-        S=3
-        erl_set "-boot_var"
-        erl_set "$2"
-        erl_set "$3"
-        ;;
-    --pipe-to)
-        S=3
-        RUN_ERL_PIPE="$2"
-        RUN_ERL_LOG="$3"
-        if [ "$(starts_with "$RUN_ERL_PIPE" "-")" ]; then
-          echo "--pipe-to : PIPEDIR cannot be a switch" >&2 && exit 1
-        elif [ "$(starts_with "$RUN_ERL_LOG" "-")" ]; then
-          echo "--pipe-to : LOGDIR cannot be a switch" >&2 && exit 1
-        fi
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        ERL="$ERL "$VAL""
         ;;
     --werl)
-        if [ "$OS" = "Windows_NT" ]; then ERL_EXEC="werl"; fi
+        USE_WERL=true
         ;;
     *)
-        while [ $I -le $LENGTH ]; do
-          I=$((I + 1))
-          set -- "$@" "$1"
-          shift
-        done
         break
         ;;
   esac
-
-  I=$((I + S))
-  shift $S
-done
-
-I=$((E - 1))
-while [ $I -ge 0 ]; do
-  eval "VAL=\$E$I"
-  set -- "$VAL" "$@"
-  I=$((I - 1))
+  I=$(expr $I + $S)
 done
 
 SELF=$(readlink_f "$0")
@@ -215,30 +106,21 @@ SCRIPT_PATH=$(dirname "$SELF")
 if [ "$OSTYPE" = "cygwin" ]; then SCRIPT_PATH=$(cygpath -m "$SCRIPT_PATH"); fi
 if [ "$MODE" != "iex" ]; then ERL="-noshell -s elixir start_cli $ERL"; fi
 
-if [ "$OS" != "Windows_NT" ] && [ -z "$NO_COLOR" ]; then
+# Check for terminal support
+if [ "$OS" != "Windows_NT" ]; then
   if test -t 1 -a -t 2; then ERL="-elixir ansi_enabled true $ERL"; fi
 fi
 
-# One MAY change ERTS_BIN= but you MUST NOT change
-# ERTS_BIN=$ERTS_BIN as it is handled by Elixir releases.
-ERTS_BIN=
-ERTS_BIN="$ERTS_BIN"
-
-set -- "$ERTS_BIN$ERL_EXEC" -pa "$SCRIPT_PATH"/../lib/*/ebin $ELIXIR_ERL_OPTIONS $ERL "$@"
-
-if [ -n "$RUN_ERL_PIPE" ]; then
-  ESCAPED=""
-  for PART in "$@"; do
-    ESCAPED="$ESCAPED $(echo "$PART" | sed 's/[^a-zA-Z0-9_\-\/]/\\&/g')"
-  done
-  mkdir -p "$RUN_ERL_PIPE"
-  mkdir -p "$RUN_ERL_LOG"
-  ERL_EXEC="run_erl"
-  set -- "$ERTS_BIN$ERL_EXEC" -daemon "$RUN_ERL_PIPE/" "$RUN_ERL_LOG/" "$ESCAPED"
+if [ "$OS" = "Windows_NT" ] && [ $USE_WERL ]; then
+    ERL_EXEC="werl"
 fi
 
-if [ -n "$ELIXIR_CLI_DRY_RUN" ]; then
-  echo "$@"
-else
-  exec "$@"
+if [ -z "$ERL_PATH" ]; then
+  if [ -f "$SCRIPT_PATH/../releases/RELEASES" ] && [ -f "$SCRIPT_PATH/erl" ]; then
+    ERL_PATH="$SCRIPT_PATH"/"$ERL_EXEC"
+  else
+    ERL_PATH="$ERL_EXEC"
+  fi
 fi
+
+exec "$ERL_PATH" -pa "$SCRIPT_PATH"/../lib/*/ebin $ELIXIR_ERL_OPTIONS $ERL -extra "$@"

bin/elixir.bat

@@ -1,183 +1,113 @@
 @if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-
-set ELIXIR_VERSION=1.13.3
-
-setlocal enabledelayedexpansion
-if    ""%1""==""""                if ""%2""=="""" goto documentation
-if /I ""%1""==""--help""          if ""%2""=="""" goto documentation
-if /I ""%1""==""-h""              if ""%2""=="""" goto documentation
-if /I ""%1""==""/h""              if ""%2""=="""" goto documentation
-if    ""%1""==""/?""              if ""%2""=="""" goto documentation
-if /I ""%1""==""--short-version"" if ""%2""=="""" goto shortversion
+setlocal
+if    ""%1""==""""       goto documentation
+if /I ""%1""==""--help"" goto documentation
+if /I ""%1""==""-h""     goto documentation
+if /I ""%1""==""/h""     goto documentation
+if    ""%1""==""/?""     goto documentation
 goto parseopts
 
 :documentation
 echo Usage: %~nx0 [options] [.exs file] [data]
 echo.
-echo ## General options
+echo   -v                          Prints version and exits
+echo   -e COMMAND                  Evaluates the given command (*)
+echo   -r FILE                     Requires the given files/patterns (*)
+echo   -S SCRIPT                   Finds and executes the given script in PATH
+echo   -pr FILE                    Requires the given files/patterns in parallel (*)
+echo   -pa PATH                    Prepends the given path to Erlang code path (*)
+echo   -pz PATH                    Appends the given path to Erlang code path (*)
 echo.
-echo   -e "COMMAND"                 Evaluates the given command (*)
-echo   -h, --help                   Prints this message (standalone)
-echo   -r "FILE"                    Requires the given files/patterns (*)
-echo   -S SCRIPT                    Finds and executes the given script in $PATH
-echo   -pr "FILE"                   Requires the given files/patterns in parallel (*)
-echo   -pa "PATH"                   Prepends the given path to Erlang code path (*)
-echo   -pz "PATH"                   Appends the given path to Erlang code path (*)
-echo   -v, --version                Prints Erlang/OTP and Elixir versions (standalone)
+echo   --app APP                   Starts the given app and its dependencies (*)
+echo   --cookie COOKIE             Sets a cookie for this distributed node
+echo   --detached                  Starts the Erlang VM detached from console
+echo   --erl SWITCHES              Switches to be passed down to Erlang (*)
+echo   --hidden                    Makes a hidden node
+echo   --logger-otp-reports BOOL   Enables or disables OTP reporting
+echo   --logger-sasl-reports BOOL  Enables or disables SASL reporting
+echo   --name NAME                 Makes and assigns a name to the distributed node
+echo   --no-halt                   Does not halt the Erlang VM after execution
+echo   --sname NAME                Makes and assigns a short name to the distributed node
+echo   --werl                      Uses Erlang's Windows shell GUI
 echo.
-echo   --app APP                    Starts the given app and its dependencies (*)
-echo   --erl "SWITCHES"             Switches to be passed down to Erlang (*)
-echo   --eval "COMMAND"             Evaluates the given command, same as -e (*)
-echo   --logger-otp-reports BOOL    Enables or disables OTP reporting
-echo   --logger-sasl-reports BOOL   Enables or disables SASL reporting
-echo   --no-halt                    Does not halt the Erlang VM after execution
-echo   --short-version              Prints Elixir version (standalone)
-echo   --werl                       Uses Erlang's Windows shell GUI (Windows only)
-echo.
-echo Options given after the .exs file or -- are passed down to the executed code.
-echo Options can be passed to the Erlang runtime using $ELIXIR_ERL_OPTIONS or --erl.
-echo.
-echo ## Distribution options
-echo.
-echo The following options are related to node distribution.
-echo.
-echo   --cookie COOKIE              Sets a cookie for this distributed node
-echo   --hidden                     Makes a hidden node
-echo   --name NAME                  Makes and assigns a name to the distributed node
-echo   --rpc-eval NODE "COMMAND"    Evaluates the given command on the given remote node (*)
-echo   --sname NAME                 Makes and assigns a short name to the distributed node
-echo.
-echo ## Release options
-echo.
-echo The following options are generally used under releases.
-echo.
-echo   --boot "FILE"                Uses the given FILE.boot to start the system
-echo   --boot-var VAR "VALUE"       Makes $VAR available as VALUE to FILE.boot (*)
-echo   --erl-config "FILE"          Loads configuration in FILE.config written in Erlang (*)
-echo   --vm-args "FILE"             Passes the contents in file as arguments to the VM
-echo.
-echo --pipe-to is not supported on Windows. If set, Elixir won't boot.
-echo.
-echo ** Options marked with (*) can be given more than once.
-echo ** Standalone options can't be combined with other options.
-goto end
-
-:shortversion
-echo !ELIXIR_VERSION!
+echo ** Options marked with (*) can be given more than once
+echo ** Options given after the .exs file or -- are passed down to the executed code
+echo ** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS or --erl
 goto end
 
 :parseopts
 
-rem Parameters for Elixir
-set parsElixir=
-
 rem Parameters for Erlang
 set parsErlang=
 
+rem Make sure we keep a copy of all parameters
+set allPars=%*
+
+rem Get the original path name from the batch file
+set originPath=%~dp0
+
 rem Optional parameters before the "-extra" parameter
 set beforeExtra=
 
-rem Option which determines whether the loop is over
-set endLoop=0
+rem Flag which determines whether or not to use werl vs erl
+set useWerl=0
 
 rem Designates which mode / Elixir component to run as
 set runMode="elixir"
 
-rem Designates the path to the current script
-set SCRIPT_PATH=%~dp0
-
-rem Designates the path to the ERTS system
-set ERTS_BIN=
-set ERTS_BIN=!ERTS_BIN!
-
 rem Recursive loop called for each parameter that parses the cmd line parameters
 :startloop
-set "par=%~1"
-if "!par!"=="" (
-  rem skip if no parameter
+set par="%1"
+shift
+if "%par%"=="" (
+  rem if no parameters defined
   goto expand_erl_libs
 )
-shift
-set par="!par:"=\"!"
-if !endLoop! == 1 (
-  set parsElixir=!parsElixir! !par!
-  goto startloop
+if "%par%"=="""" (
+  rem if no parameters defined - special case for parameter that is already quoted
+  goto expand_erl_libs
 )
 rem ******* EXECUTION OPTIONS **********************
-if !par!=="--werl"   (set useWerl=1 && goto startloop)
-if !par!=="+iex"     (set parsElixir=!parsElixir! +iex && set runMode="iex" && goto startloop)
-if !par!=="+elixirc" (set parsElixir=!parsElixir! +elixirc && set runMode="elixirc" && goto startloop)
-rem ******* EVAL PARAMETERS ************************
-if ""==!par:-e=! (
-  set "VAR=%~1"
-  if not defined VAR (set VAR= )
-  set parsElixir=!parsElixir! -e "!VAR:"=\"!"
-  shift
-  goto startloop
-)
-if ""==!par:--eval=! (
-  set "VAR=%~1"
-  if not defined VAR (set VAR= )
-  set parsElixir=!parsElixir! --eval "!VAR:"=\"!"
-  shift
-  goto startloop
-)
-if ""==!par:--rpc-eval=! (
-  set "VAR=%~2"
-  if not defined VAR (set VAR= )
-  set parsElixir=!parsElixir! --rpc-eval %1 "!VAR:"=\"!"
-  shift
-  shift
-  goto startloop
-)
+if "%par%"==""--werl"" (set useWerl=1)
+if "%par%"==""+iex"" (set runMode="iex")
 rem ******* ELIXIR PARAMETERS **********************
-if ""==!par:-r=!          (set "parsElixir=!parsElixir! -r %1" && shift && goto startloop)
-if ""==!par:-pr=!         (set "parsElixir=!parsElixir! -pr %1" && shift && goto startloop)
-if ""==!par:-pa=!         (set "parsElixir=!parsElixir! -pa %1" && shift && goto startloop)
-if ""==!par:-pz=!         (set "parsElixir=!parsElixir! -pz %1" && shift && goto startloop)
-if ""==!par:-v=!          (set "parsElixir=!parsElixir! -v" && goto startloop)
-if ""==!par:--version=!   (set "parsElixir=!parsElixir! --version" && goto startloop)
-if ""==!par:--app=!       (set "parsElixir=!parsElixir! --app %1" && shift && goto startloop)
-if ""==!par:--no-halt=!   (set "parsElixir=!parsElixir! --no-halt" && goto startloop)
-if ""==!par:--remsh=!     (set "parsElixir=!parsElixir! --remsh %1" && shift && goto startloop)
-if ""==!par:--dot-iex=!   (set "parsElixir=!parsElixir! --dot-iex %1" && shift && goto startloop)
+rem Note: we don't have to do anything with options that don't take an argument
+if """"=="%par:-e=%"      (shift)
+if """"=="%par:-r=%"      (shift)
+if """"=="%par:-pr=%"     (shift)
+if """"=="%par:-pa=%"     (shift)
+if """"=="%par:-pz=%"     (shift)
+if """"=="%par:--app=%"   (shift)
+if """"=="%par:--remsh=%" (shift)
 rem ******* ERLANG PARAMETERS **********************
-if ""==!par:--boot=!                (set "parsErlang=!parsErlang! -boot %1" && shift && goto startloop)
-if ""==!par:--boot-var=!            (set "parsErlang=!parsErlang! -boot_var %1 %2" && shift && shift && goto startloop)
-if ""==!par:--cookie=!              (set "parsErlang=!parsErlang! -setcookie %1" && shift && goto startloop)
-if ""==!par:--hidden=!              (set "parsErlang=!parsErlang! -hidden" && goto startloop)
-if ""==!par:--detached=!            (set "parsErlang=!parsErlang! -detached" && echo warning: the --detached option is deprecated && goto startloop)
-if ""==!par:--erl-config=!          (set "parsErlang=!parsErlang! -config %1" && shift && goto startloop)
-if ""==!par:--logger-otp-reports=!  (set "parsErlang=!parsErlang! -logger handle_otp_reports %1" && shift && goto startloop)
-if ""==!par:--logger-sasl-reports=! (set "parsErlang=!parsErlang! -logger handle_sasl_reports %1" && shift && goto startloop)
-if ""==!par:--name=!                (set "parsErlang=!parsErlang! -name %1" && shift && goto startloop)
-if ""==!par:--sname=!               (set "parsErlang=!parsErlang! -sname %1" && shift && goto startloop)
-if ""==!par:--vm-args=!             (set "parsErlang=!parsErlang! -args_file %1" && shift && goto startloop)
-if ""==!par:--erl=!                 (set "beforeExtra=!beforeExtra! %~1" && shift && goto startloop)
-if ""==!par:--pipe-to=!             (echo --pipe-to : Option is not supported on Windows && goto end)
-set endLoop=1
-set parsElixir=!parsElixir! !par!
-goto startloop
+if """"=="%par:--detached=%"            (set parsErlang=%parsErlang% -detached)
+if """"=="%par:--hidden=%"              (set parsErlang=%parsErlang% -hidden)
+if """"=="%par:--cookie=%"              (set parsErlang=%parsErlang% -setcookie %1 && shift)
+if """"=="%par:--sname=%"               (set parsErlang=%parsErlang% -sname %1 && shift)
+if """"=="%par:--name=%"                (set parsErlang=%parsErlang% -name %1 && shift)
+if """"=="%par:--logger-otp-reports=%"  (set parsErlang=%parsErlang% -logger handle_otp_reports %1 && shift)
+if """"=="%par:--logger-sasl-reports=%" (set parsErlang=%parsErlang% -logger handle_sasl_reports %1 && shift)
+if """"=="%par:--erl=%"                 (set beforeExtra=%beforeExtra% %~1 && shift)
+goto:startloop
 
+rem ******* assume all pre-params are parsed ********************
 :expand_erl_libs
-rem expand all ebin paths as Windows does not support the ..\*\ebin wildcard
+rem ******* expand all ebin paths as Windows does not support the ..\*\ebin wildcard ********************
+setlocal enabledelayedexpansion
 set ext_libs=
-for  /d %%d in ("!SCRIPT_PATH!..\lib\*.") do (
+for  /d %%d in ("%originPath%..\lib\*.") do (
   set ext_libs=!ext_libs! -pa "%%~fd\ebin"
 )
+setlocal disabledelayedexpansion
 
 :run
-reg query HKCU\Console /v VirtualTerminalLevel 2>nul | findstr /e "0x1" >nul 2>nul
-if %errorlevel% == 0 (
-  set beforeExtra=-elixir ansi_enabled true !beforeExtra!
+if not %runMode% == "iex" (
+  set beforeExtra=-noshell -s elixir start_cli %beforeExtra%
 )
-if not !runMode! == "iex" (
-  set beforeExtra=-noshell -s elixir start_cli !beforeExtra!
-)
-if defined useWerl (
-  start "" "!ERTS_BIN!werl.exe" !ext_libs! !ELIXIR_ERL_OPTIONS! !parsErlang! !beforeExtra! -extra !parsElixir!
+if %useWerl% equ 1 (
+  start werl.exe %ext_libs% %ELIXIR_ERL_OPTIONS% %parsErlang% %beforeExtra% -extra %*
 ) else (
-  "!ERTS_BIN!erl.exe" !ext_libs! !ELIXIR_ERL_OPTIONS! !parsErlang! !beforeExtra! -extra !parsElixir!
+  erl.exe %ext_libs% %ELIXIR_ERL_OPTIONS% %parsErlang% %beforeExtra% -extra %*
 )
 :end
 endlocal

bin/elixirc

@@ -1,25 +1,17 @@
 #!/bin/sh
-set -e
-
 if [ $# -eq 0 ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
-  cat <<USAGE >&2
-Usage: $(basename "$0") [elixir switches] [compiler switches] [.ex files]
+  echo "Usage: `basename $0` [elixir switches] [compiler switches] [.ex files]
 
-  -h, --help                Prints this message and exits
-  -o                        The directory to output compiled files
-  -v, --version             Prints Elixir version and exits (standalone)
+  -o                   The directory to output compiled files
+  --no-docs            Do not attach documentation to compiled modules
+  --no-debug-info      Do not attach debug info to compiled modules
+  --verbose            Print compilation status
+  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+  --ignore-module-conflict
 
-  --ignore-module-conflict  Does not emit warnings if a module was previously defined
-  --no-debug-info           Does not attach debug info to compiled modules
-  --no-docs                 Does not attach documentation to compiled modules
-  --profile time            Profile the time to compile modules
-  --verbose                 Prints compilation status
-  --warnings-as-errors      Treats warnings as errors and return non-zero exit status
-
-Options given after -- are passed down to the executed code.
-Options can be passed to the Erlang runtime using \$ELIXIR_ERL_OPTIONS.
-Options can be passed to the Erlang compiler using \$ERL_COMPILER_OPTIONS.
-USAGE
+** Options given after -- are passed down to the executed code
+** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS
+** Options can be passed to the Erlang compiler using ERL_COMPILER_OPTIONS" >&2
   exit 1
 fi
 
@@ -29,7 +21,7 @@ readlink_f () {
   if [ -h "$filename" ]; then
     readlink_f "$(readlink "$filename")"
   else
-    echo "$(pwd -P)/$filename"
+    echo "`pwd -P`/$filename"
   fi
 }
 

bin/elixirc.bat

@@ -14,16 +14,12 @@ goto run
 :documentation
 echo Usage: %~nx0 [elixir switches] [compiler switches] [.ex files]
 echo.
-echo   -h, --help                Prints this message and exits
-echo   -o                        The directory to output compiled files
-echo   -v, --version             Prints Elixir version and exits (standalone)
-echo.
-echo   --ignore-module-conflict  Does not emit warnings if a module was previously defined
-echo   --no-debug-info           Does not attach debug info to compiled modules
-echo   --no-docs                 Does not attach documentation to compiled modules
-echo   --profile time            Profile the time to compile modules
-echo   --verbose                 Prints compilation status
-echo   --warnings-as-errors      Treats warnings as errors and returns non-zero exit status
+echo  -o                   The directory to output compiled files
+echo  --no-docs            Do not attach documentation to compiled modules
+echo  --no-debug-info      Do not attach debug info to compiled modules
+echo  --verbose            Print compilation status
+echo  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+echo  --ignore-module-conflict
 echo.
 echo ** Options given after -- are passed down to the executed code
 echo ** Options can be passed to the Erlang runtime using ELIXIR_ERL_OPTIONS

bin/iex

@@ -1,18 +1,34 @@
 #!/bin/sh
-set -e
+if [ $# -gt 0 ] && ([ "$1" = "--help" ] || [ "$1" = "-h" ]); then
+  echo "Usage: `basename $0` [options] [.exs file] [data]
 
-if [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
-  cat <<USAGE >&2
-Usage: $(basename "$0") [options] [.exs file] [data]
+  -v                          Prints version and exits
+  -e COMMAND                  Evaluates the given command (*)
+  -r FILE                     Requires the given files/patterns (*)
+  -S SCRIPT                   Finds and executes the given script in PATH
+  -pr FILE                    Requires the given files/patterns in parallel (*)
+  -pa PATH                    Prepends the given path to Erlang code path (*)
+  -pz PATH                    Appends the given path to Erlang code path (*)
 
-The following options are exclusive to IEx:
+  --app APP                   Starts the given app and its dependencies (*)
+  --cookie COOKIE             Sets a cookie for this distributed node
+  --detached                  Starts the Erlang VM detached from console
+  --erl SWITCHES              Switches to be passed down to Erlang (*)
+  --hidden                    Makes a hidden node
+  --logger-otp-reports BOOL   Enables or disables OTP reporting
+  --logger-sasl-reports BOOL  Enables or disables SASL reporting
+  --name NAME                 Makes and assigns a name to the distributed node
+  --no-halt                   Does not halt the Erlang VM after execution
+  --sname NAME                Makes and assigns a short name to the distributed node
+  --werl                      Uses Erlang's Windows shell GUI (Windows only)
 
-  --dot-iex "PATH"    Overrides default .iex.exs file and uses path instead;
-                      path can be empty, then no file will be loaded
-  --remsh NAME        Connects to a node using a remote shell
+  --dot-iex PATH              Overrides default .iex.exs file and uses path instead;
+                              path can be empty, then no file will be loaded
+  --remsh NAME                Connects to a node using a remote shell
 
-It accepts all other options listed by "elixir --help".
-USAGE
+** Options marked with (*) can be given more than once
+** Options given after the .exs file or -- are passed down to the executed code
+** Options can be passed to the VM using ELIXIR_ERL_OPTIONS or --erl" >&2
   exit 1
 fi
 
@@ -22,10 +38,10 @@ readlink_f () {
   if [ -h "$filename" ]; then
     readlink_f "$(readlink "$filename")"
   else
-    echo "$(pwd -P)/$filename"
+    echo "`pwd -P`/$filename"
   fi
 }
 
 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-exec "$SCRIPT_PATH"/elixir --no-halt --erl "-noshell -user Elixir.IEx.CLI" +iex "$@"
+exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user Elixir.IEx.CLI" +iex "$@"

bin/iex.bat

@@ -1,4 +1,4 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
+@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
 setlocal
 if /I ""%1""==""--help"" goto documentation
 if /I ""%1""==""-h""     goto documentation
@@ -9,19 +9,37 @@ goto run
 :documentation
 echo Usage: %~nx0 [options] [.exs file] [data]
 echo.
-echo The following options are exclusive to IEx:
+echo  -v                          Prints version and exits
+echo  -e COMMAND                  Evaluates the given command (*)
+echo  -r FILE                     Requires the given files/patterns (*)
+echo  -S SCRIPT                   Finds and executes the given script in PATH
+echo  -pr FILE                    Requires the given files/patterns in parallel (*)
+echo  -pa PATH                    Prepends the given path to Erlang code path (*)
+echo  -pz PATH                    Appends the given path to Erlang code path (*)
 echo.
-echo   --dot-iex "PATH"    Overrides default .iex.exs file and uses path instead;
-echo                       path can be empty, then no file will be loaded
-echo   --remsh NAME        Connects to a node using a remote shell
-echo   --werl              Uses Erlang's Windows shell GUI (Windows only)
+echo  --app APP                   Starts the given app and its dependencies (*)
+echo  --cookie COOKIE             Sets a cookie for this distributed node
+echo  --detached                  Starts the Erlang VM detached from console
+echo  --erl SWITCHES              Switches to be passed down to Erlang (*)
+echo  --hidden                    Makes a hidden node
+echo  --logger-otp-reports BOOL   Enables or disables OTP reporting
+echo  --logger-sasl-reports BOOL  Enables or disables SASL reporting
+echo  --name NAME                 Makes and assigns a name to the distributed node
+echo  --no-halt                   Does not halt the Erlang VM after execution
+echo  --sname NAME                Makes and assigns a short name to the distributed node
+echo  --werl                      Uses Erlang's Windows shell GUI (Windows only)
 echo.
-echo Set the IEX_WITH_WERL environment variable to always use werl.
-echo It accepts all other options listed by "elixir --help".
+echo  --dot-iex PATH              Overrides default .iex.exs file and uses path instead;
+echo                              path can be empty, then no file will be loaded
+echo  --remsh NAME                Connects to a node using a remote shell
+echo.
+echo ** Options marked with (*) can be given more than once
+echo ** Options given after the .exs file or -- are passed down to the executed code
+echo ** Options can be passed to the Erlang VM using ELIXIR_ERL_OPTIONS or --erl
 goto end
 
 :run
-if defined IEX_WITH_WERL (@set __ELIXIR_IEX_FLAGS=--werl) else (set __ELIXIR_IEX_FLAGS=)
-call "%~dp0\elixir.bat" --no-halt --erl "-noshell -user Elixir.IEx.CLI" +iex %__ELIXIR_IEX_FLAGS% %*
+@if defined IEX_WITH_WERL (@set __ELIXIR_IEX_FLAGS=--werl) else (set __ELIXIR_IEX_FLAGS=)
+call "%~dp0\elixir.bat" +iex --erl "-user Elixir.IEx.CLI" --no-halt %__ELIXIR_IEX_FLAGS% %*
 :end
 endlocal

bin/mix

@@ -1,3 +1,3 @@
 #!/usr/bin/env elixir
-Mix.start()
-Mix.CLI.main()
+Mix.start
+Mix.CLI.main

lib/eex/lib/eex.ex

@@ -1,9 +1,8 @@
 defmodule EEx.SyntaxError do
-  defexception [:message, :file, :line, :column]
+  defexception [:message, :file, :line]
 
-  @impl true
   def message(exception) do
-    "#{exception.file}:#{exception.line}:#{exception.column}: #{exception.message}"
+    "#{exception.file}:#{exception.line}: #{exception.message}"
   end
 end
 
@@ -12,24 +11,24 @@ defmodule EEx do
   EEx stands for Embedded Elixir. It allows you to embed
   Elixir code inside a string in a robust way.
 
-      iex> EEx.eval_string("foo <%= bar %>", bar: "baz")
+      iex> EEx.eval_string "foo <%= bar %>", [bar: "baz"]
       "foo baz"
 
   ## API
 
-  This module provides three main APIs for you to use:
+  This module provides 3 main APIs for you to use:
 
-    1. Evaluate a string (`eval_string/3`) or a file (`eval_file/3`)
+    1. Evaluate a string (`eval_string`) or a file (`eval_file`)
        directly. This is the simplest API to use but also the
-       slowest, since the code is evaluated at runtime and not precompiled.
+       slowest, since the code is evaluated and not compiled before.
 
-    2. Define a function from a string (`function_from_string/5`)
-       or a file (`function_from_file/5`). This allows you to embed
+    2. Define a function from a string (`function_from_string`)
+       or a file (`function_from_file`). This allows you to embed
        the template as a function inside a module which will then
        be compiled. This is the preferred API if you have access
        to the template at compilation time.
 
-    3. Compile a string (`compile_string/2`) or a file (`compile_file/2`)
+    3. Compile a string (`compile_string`) or a file (`compile_file`)
        into Elixir syntax tree. This is the API used by both functions
        above and is available to you if you want to provide your own
        ways of handling the compiled template.
@@ -39,19 +38,11 @@ defmodule EEx do
   All functions in this module accept EEx-related options.
   They are:
 
+    * `:line` - the line to be used as the template start. Defaults to 1.
     * `:file` - the file to be used in the template. Defaults to the given
-      file the template is read from or to `"nofile"` when compiling from a string.
-    * `:line` - the line to be used as the template start. Defaults to `1`.
-    * `:indentation` - (since v1.11.0) an integer added to the column after every
-      new line. Defaults to `0`.
+      file the template is read from or to "nofile" when compiling from a string.
     * `:engine` - the EEx engine to be used for compilation.
-    * `:trim` - if `true`, trims whitespace left and right of quotation as
-      long as at least one newline is present. All subsequent newlines and
-      spaces are removed but one newline is retained. Defaults to `false`.
-    * `:parser_options` - (since: 1.13.0) allow customizing the parsed code that is generated.
-      See `Code.string_to_quoted/2` for available options. Note that the options
-      `:file`, `:line` and `:column` are ignored if passed in.
-      Defaults to `Code.get_compiler_option(:parser_options)` (which defaults to `[]` if not set).
+    * `:trim` - trims whitespace left/right of quotation tags
 
   ## Engine
 
@@ -74,7 +65,7 @@ defmodule EEx do
   **must** use the equals sign (`=`). Since everything in
   Elixir is an expression, there are no exceptions for this rule.
   For example, while some template languages would special-case
-  `if` clauses, they are treated the same in EEx and
+  `if/2` clauses, they are treated the same in EEx and
   also require `=` in order to have their result printed:
 
       <%= if true do %>
@@ -83,13 +74,7 @@ defmodule EEx do
         This will never appear
       <% end %>
 
-  To escape an EEx expression in EEx use `<%% content %>`. For example:
-
-      <%%= x + 3 %>
-
-  will be rendered as `<%= x + 3 %>`.
-
-  Note that different engines may have different rules
+  Notice that different engines may have different rules
   for each tag. Other tags may be added in future versions.
 
   ### Macros
@@ -98,7 +83,7 @@ defmodule EEx do
   An example is the `@` macro which allows easy data access
   in a template:
 
-      iex> EEx.eval_string("<%= @foo %>", assigns: [foo: 1])
+      iex> EEx.eval_string "<%= @foo %>", assigns: [foo: 1]
       "1"
 
   In other words, `<%= @foo %>` translates to:
@@ -110,33 +95,30 @@ defmodule EEx do
   """
 
   @doc """
-  Generates a function definition from the given string.
+  Generates a function definition from the string.
 
-  The first argument is the kind of the generated function (`:def` or `:defp`).
-  The `name` argument is the name that the generated function will have.
-  `template` is the string containing the EEx template. `args` is a list of arguments
-  that the generated function will accept. They will be available inside the EEx
-  template. `options` is a list of EEx compilation options (see the module documentation).
+  The kind (`:def` or `:defp`) must be given, the
+  function name, its arguments and the compilation options.
 
   ## Examples
 
       iex> defmodule Sample do
       ...>   require EEx
-      ...>   EEx.function_from_string(:def, :sample, "<%= a + b %>", [:a, :b])
+      ...>   EEx.function_from_string :def, :sample, "<%= a + b %>", [:a, :b]
       ...> end
       iex> Sample.sample(1, 2)
       "3"
 
   """
-  defmacro function_from_string(kind, name, template, args \\ [], options \\ []) do
+  defmacro function_from_string(kind, name, source, args \\ [], options \\ []) do
     quote bind_quoted: binding() do
-      info = Keyword.merge([file: __ENV__.file, line: __ENV__.line], options)
-      args = Enum.map(args, fn arg -> {arg, [line: info[:line]], nil} end)
-      compiled = EEx.compile_string(template, info)
+      info = Keyword.merge [file: __ENV__.file, line: __ENV__.line], options
+      args = Enum.map args, fn arg -> {arg, [line: info[:line]], nil} end
+      compiled = EEx.compile_string(source, info)
 
       case kind do
-        :def -> def unquote(name)(unquote_splicing(args)), do: unquote(compiled)
-        :defp -> defp unquote(name)(unquote_splicing(args)), do: unquote(compiled)
+        :def  -> def(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
+        :defp -> defp(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
       end
     end
   end
@@ -144,11 +126,8 @@ defmodule EEx do
   @doc """
   Generates a function definition from the file contents.
 
-  The first argument is the kind of the generated function (`:def` or `:defp`).
-  The `name` argument is the name that the generated function will have.
-  `file` is the path to the EEx template file. `args` is a list of arguments
-  that the generated function will accept. They will be available inside the EEx
-  template. `options` is a list of EEx compilation options (see the module documentation).
+  The kind (`:def` or `:defp`) must be given, the
+  function name, its arguments and the compilation options.
 
   This function is useful in case you have templates but
   you want to precompile inside a module for speed.
@@ -161,84 +140,44 @@ defmodule EEx do
       # sample.ex
       defmodule Sample do
         require EEx
-        EEx.function_from_file(:def, :sample, "sample.eex", [:a, :b])
+        EEx.function_from_file :def, :sample, "sample.eex", [:a, :b]
       end
 
       # iex
-      Sample.sample(1, 2)
-      #=> "3"
+      Sample.sample(1, 2) #=> "3"
 
   """
   defmacro function_from_file(kind, name, file, args \\ [], options \\ []) do
     quote bind_quoted: binding() do
-      info = Keyword.merge([file: IO.chardata_to_string(file), line: 1], options)
-      args = Enum.map(args, fn arg -> {arg, [line: 1], nil} end)
+      info = Keyword.merge options, [file: file, line: 1]
+      args = Enum.map args, fn arg -> {arg, [line: 1], nil} end
       compiled = EEx.compile_file(file, info)
 
       @external_resource file
       @file file
       case kind do
-        :def -> def unquote(name)(unquote_splicing(args)), do: unquote(compiled)
-        :defp -> defp unquote(name)(unquote_splicing(args)), do: unquote(compiled)
+        :def  -> def(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
+        :defp -> defp(unquote(name)(unquote_splicing(args)), do: unquote(compiled))
       end
     end
   end
 
   @doc """
-  Gets a string `source` and generates a quoted expression
+  Gets a string `source` and generate a quoted expression
   that can be evaluated by Elixir or compiled to a function.
-
-  This is useful if you want to compile a EEx template into code and inject
-  that code somewhere or evaluate it at runtime.
-
-  The generated quoted code will use variables defined in the template that
-  will be taken from the context where the code is evaluated. If you
-  have a template such as `<%= a + b %>`, then the returned quoted code
-  will use the `a` and `b` variables in the context where it's evaluated. See
-  examples below.
-
-  ## Examples
-
-      iex> quoted = EEx.compile_string("<%= a + b %>")
-      iex> {result, _bindings} = Code.eval_quoted(quoted, a: 1, b: 2)
-      iex> result
-      "3"
-
   """
-  @spec compile_string(String.t(), keyword) :: Macro.t()
+  @spec compile_string(String.t, Keyword.t) :: Macro.t | no_return
   def compile_string(source, options \\ []) when is_binary(source) and is_list(options) do
     EEx.Compiler.compile(source, options)
   end
 
   @doc """
-  Gets a `filename` and generates a quoted expression
+  Gets a `filename` and generate a quoted expression
   that can be evaluated by Elixir or compiled to a function.
-
-  This is useful if you want to compile a EEx template into code and inject
-  that code somewhere or evaluate it at runtime.
-
-  The generated quoted code will use variables defined in the template that
-  will be taken from the context where the code is evaluated. If you
-  have a template such as `<%= a + b %>`, then the returned quoted code
-  will use the `a` and `b` variables in the context where it's evaluated. See
-  examples below.
-
-  ## Examples
-
-      # sample.eex
-      <%= a + b %>
-
-      # In code:
-      quoted = EEx.compile_file("sample.eex")
-      {result, _bindings} = Code.eval_quoted(quoted, a: 1, b: 2)
-      result
-      #=> "3"
-
   """
-  @spec compile_file(Path.t(), keyword) :: Macro.t()
-  def compile_file(filename, options \\ []) when is_list(options) do
-    filename = IO.chardata_to_string(filename)
-    options = Keyword.merge([file: filename, line: 1], options)
+  @spec compile_file(String.t, Keyword.t) :: Macro.t | no_return
+  def compile_file(filename, options \\ []) when is_binary(filename) and is_list(options) do
+    options = Keyword.merge options, [file: filename, line: 1]
     compile_string(File.read!(filename), options)
   end
 
@@ -247,11 +186,11 @@ defmodule EEx do
 
   ## Examples
 
-      iex> EEx.eval_string("foo <%= bar %>", bar: "baz")
+      iex> EEx.eval_string "foo <%= bar %>", [bar: "baz"]
       "foo baz"
 
   """
-  @spec eval_string(String.t(), keyword, keyword) :: String.t()
+  @spec eval_string(String.t, Keyword.t, Keyword.t) :: any
   def eval_string(source, bindings \\ [], options \\ [])
       when is_binary(source) and is_list(bindings) and is_list(options) do
     compiled = compile_string(source, options)
@@ -266,16 +205,14 @@ defmodule EEx do
       # sample.eex
       foo <%= bar %>
 
-      # IEx
-      EEx.eval_file("sample.eex", bar: "baz")
-      #=> "foo baz"
+      # iex
+      EEx.eval_file "sample.eex", [bar: "baz"] #=> "foo baz"
 
   """
-  @spec eval_file(Path.t(), keyword, keyword) :: String.t()
+  @spec eval_file(String.t, Keyword.t, Keyword.t) :: any
   def eval_file(filename, bindings \\ [], options \\ [])
-      when is_list(bindings) and is_list(options) do
-    filename = IO.chardata_to_string(filename)
-    options = Keyword.put_new(options, :file, filename)
+      when is_binary(filename) and is_list(bindings) and is_list(options) do
+    options  = Keyword.put options, :file, filename
     compiled = compile_file(filename, options)
     do_eval(compiled, bindings, options)
   end

lib/eex/lib/eex/compiler.ex

@@ -9,176 +9,66 @@ defmodule EEx.Compiler do
   and the engine together by handling the tokens and invoking
   the engine every time a full expression or text is received.
   """
-  @spec compile(String.t(), keyword) :: Macro.t()
+  @spec compile(String.t, Keyword.t) :: Macro.t | no_return
   def compile(source, opts) when is_binary(source) and is_list(opts) do
-    file = opts[:file] || "nofile"
-    line = opts[:line] || 1
-    column = 1
-    indentation = opts[:indentation] || 0
-    trim = opts[:trim] || false
-    parser_options = opts[:parser_options] || Code.get_compiler_option(:parser_options)
-    tokenizer_options = %{trim: trim, indentation: indentation}
-
-    case EEx.Tokenizer.tokenize(source, line, column, tokenizer_options) do
+    file   = opts[:file] || "nofile"
+    line   = opts[:line] || 1
+    trim   = opts[:trim] || false
+    case EEx.Tokenizer.tokenize(source, line, trim: trim) do
       {:ok, tokens} ->
-        state = %{
-          engine: opts[:engine] || @default_engine,
-          file: file,
-          line: line,
-          quoted: [],
-          start_line: nil,
-          start_column: nil,
-          parser_options: parser_options
-        }
-
-        init = state.engine.init(opts)
-        generate_buffer(tokens, init, [], state)
-
-      {:error, line, column, message} ->
-        raise EEx.SyntaxError, file: file, line: line, column: column, message: message
+        state = %{engine: opts[:engine] || @default_engine,
+                  file: file, line: line, quoted: [], start_line: nil}
+        generate_buffer(tokens, state.engine.init(opts), [], state)
+      {:error, line, message} ->
+        raise EEx.SyntaxError, line: line, file: file, message: message
     end
   end
 
   # Generates the buffers by handling each expression from the tokenizer.
   # It returns Macro.t/0 or it raises.
 
-  defp generate_buffer([{:text, line, column, chars} | rest], buffer, scope, state) do
-    buffer =
-      if function_exported?(state.engine, :handle_text, 3) do
-        meta = [line: line, column: column]
-        state.engine.handle_text(buffer, meta, IO.chardata_to_string(chars))
-      else
-        # TODO: Remove this branch on Elixir v2.0
-        state.engine.handle_text(buffer, IO.chardata_to_string(chars))
-      end
-
-    generate_buffer(rest, buffer, scope, state)
+  defp generate_buffer([{:text, chars} | t], buffer, scope, state) do
+    buffer = state.engine.handle_text(buffer, IO.chardata_to_string(chars))
+    generate_buffer(t, buffer, scope, state)
   end
 
-  defp generate_buffer([{:expr, line, column, mark, chars} | rest], buffer, scope, state) do
-    options = [file: state.file, line: line, column: column(column, mark)] ++ state.parser_options
-    expr = Code.string_to_quoted!(chars, options)
+  defp generate_buffer([{:expr, line, mark, chars} | t], buffer, scope, state) do
+    expr = Code.string_to_quoted!(chars, [line: line, file: state.file])
     buffer = state.engine.handle_expr(buffer, IO.chardata_to_string(mark), expr)
-    generate_buffer(rest, buffer, scope, state)
+    generate_buffer(t, buffer, scope, state)
   end
 
-  defp generate_buffer(
-         [{:start_expr, start_line, start_column, mark, chars} | rest],
-         buffer,
-         scope,
-         state
-       ) do
-    if mark != '=' do
-      message =
-        "the contents of this expression won't be output unless the EEx block starts with \"<%=\""
-
-      :elixir_errors.erl_warn({start_line, start_column}, state.file, message)
-    end
-
-    {rest, line, contents} =
-      look_ahead_middle(rest, start_line, chars) || {rest, start_line, chars}
-
-    {contents, rest} =
-      generate_buffer(
-        rest,
-        state.engine.handle_begin(buffer),
-        [contents | scope],
-        %{
-          state
-          | quoted: [],
-            line: line,
-            start_line: start_line,
-            start_column: column(start_column, mark)
-        }
-      )
-
+  defp generate_buffer([{:start_expr, start_line, mark, chars} | t], buffer, scope, state) do
+    {contents, line, t} = look_ahead_text(t, start_line, chars)
+    {contents, t} = generate_buffer(t, "", [contents | scope],
+                                    %{state | quoted: [], line: line, start_line: start_line})
     buffer = state.engine.handle_expr(buffer, IO.chardata_to_string(mark), contents)
-    generate_buffer(rest, buffer, scope, state)
+    generate_buffer(t, buffer, scope, state)
   end
 
-  defp generate_buffer(
-         [{:middle_expr, line, _column, '', chars} | rest],
-         buffer,
-         [current | scope],
-         state
-       ) do
+  defp generate_buffer([{:middle_expr, line, _, chars} | t], buffer, [current | scope], state) do
     {wrapped, state} = wrap_expr(current, line, buffer, chars, state)
-    state = %{state | line: line}
-    generate_buffer(rest, state.engine.handle_begin(buffer), [wrapped | scope], state)
+    generate_buffer(t, "", [wrapped | scope], %{state | line: line})
   end
 
-  defp generate_buffer(
-         [{:middle_expr, line, column, modifier, chars} | t],
-         buffer,
-         [_ | _] = scope,
-         state
-       ) do
-    message =
-      "unexpected beginning of EEx tag \"<%#{modifier}\" on \"<%#{modifier}#{chars}%>\", " <>
-        "please remove \"#{modifier}\" accordingly"
-
-    :elixir_errors.erl_warn({line, column}, state.file, message)
-    generate_buffer([{:middle_expr, line, column, '', chars} | t], buffer, scope, state)
-    # TODO: Make this an error on Elixir v2.0 since it accidentally worked previously.
-    # raise EEx.SyntaxError, message: message, file: state.file, line: line
-  end
-
-  defp generate_buffer([{:middle_expr, line, column, _, chars} | _], _buffer, [], state) do
-    raise EEx.SyntaxError,
-      message: "unexpected middle of expression <%#{chars}%>",
-      file: state.file,
-      line: line,
-      column: column
-  end
-
-  defp generate_buffer(
-         [{:end_expr, line, _column, '', chars} | rest],
-         buffer,
-         [current | _],
-         state
-       ) do
+  defp generate_buffer([{:end_expr, line, _, chars} | t], buffer, [current | _], state) do
     {wrapped, state} = wrap_expr(current, line, buffer, chars, state)
-    column = state.start_column
-    options = [file: state.file, line: state.start_line, column: column] ++ state.parser_options
-    tuples = Code.string_to_quoted!(wrapped, options)
+    tuples = Code.string_to_quoted!(wrapped, [line: state.start_line, file: state.file])
     buffer = insert_quoted(tuples, state.quoted)
-    {buffer, rest}
+    {buffer, t}
   end
 
-  defp generate_buffer(
-         [{:end_expr, line, column, modifier, chars} | t],
-         buffer,
-         [_ | _] = scope,
-         state
-       ) do
-    message =
-      "unexpected beginning of EEx tag \"<%#{modifier}\" on end of " <>
-        "expression \"<%#{modifier}#{chars}%>\", please remove \"#{modifier}\" accordingly"
-
-    :elixir_errors.erl_warn({line, column}, state.file, message)
-    generate_buffer([{:end_expr, line, column, '', chars} | t], buffer, scope, state)
-    # TODO: Make this an error on Elixir v2.0 since it accidentally worked previously.
-    # raise EEx.SyntaxError, message: message, file: state.file, line: line, column: column
+  defp generate_buffer([{:end_expr, line, _, chars} | _], _buffer, [], state) do
+    raise EEx.SyntaxError, message: "unexpected token #{inspect chars}", file: state.file, line: line
   end
 
-  defp generate_buffer([{:end_expr, line, column, _, chars} | _], _buffer, [], state) do
-    raise EEx.SyntaxError,
-      message: "unexpected end of expression <%#{chars}%>",
-      file: state.file,
-      line: line,
-      column: column
-  end
-
-  defp generate_buffer([{:eof, _, _}], buffer, [], state) do
+  defp generate_buffer([], buffer, [], state) do
     state.engine.handle_body(buffer)
   end
 
-  defp generate_buffer([{:eof, line, column}], _buffer, _scope, state) do
-    raise EEx.SyntaxError,
-      message: "unexpected end of string, expected a closing '<% end %>'",
-      file: state.file,
-      line: line,
-      column: column
+  defp generate_buffer([], _buffer, _scope, state) do
+    raise EEx.SyntaxError, message: "unexpected end of string, expected a closing '<% end %>'",
+                           file: state.file, line: state.line
   end
 
   # Creates a placeholder and wrap it inside the expression block
@@ -187,28 +77,24 @@ defmodule EEx.Compiler do
     new_lines = List.duplicate(?\n, line - state.line)
     key = length(state.quoted)
     placeholder = '__EEX__(' ++ Integer.to_charlist(key) ++ ');'
-    count = current ++ placeholder ++ new_lines ++ chars
-    new_state = %{state | quoted: [{key, state.engine.handle_end(buffer)} | state.quoted]}
-
-    {count, new_state}
+    {current ++ placeholder ++ new_lines ++ chars,
+     %{state | quoted: [{key, buffer} | state.quoted]}}
   end
 
-  # Look middle expressions that immediately follow a start_expr
+  # Look text ahead on expressions
 
-  defp look_ahead_middle([{:text, _, _, text} | rest], start, contents) do
+  defp look_ahead_text([{:text, text}, {:middle_expr, line, _, chars} | t]=list, start, contents) do
     if only_spaces?(text) do
-      look_ahead_middle(rest, start, contents ++ text)
+      {contents ++ text ++ chars, line, t}
     else
-      nil
+      {contents, start, list}
     end
   end
-
-  defp look_ahead_middle([{:middle_expr, line, _column, _, chars} | rest], _start, contents) do
-    {rest, line, contents ++ chars}
+  defp look_ahead_text([{:middle_expr, line, _, chars} | t], _start, contents) do
+    {contents ++ chars, line, t}
   end
-
-  defp look_ahead_middle(_tokens, _start, _contents) do
-    nil
+  defp look_ahead_text(t, start, contents) do
+    {contents, start, t}
   end
 
   defp only_spaces?(chars) do
@@ -218,7 +104,7 @@ defmodule EEx.Compiler do
   # Changes placeholder to real expression
 
   defp insert_quoted({:__EEX__, _, [key]}, quoted) do
-    {^key, value} = List.keyfind(quoted, key, 0)
+    {^key, value} = List.keyfind quoted, key, 0
     value
   end
 
@@ -231,15 +117,10 @@ defmodule EEx.Compiler do
   end
 
   defp insert_quoted(list, quoted) when is_list(list) do
-    Enum.map(list, &insert_quoted(&1, quoted))
+    Enum.map list, &insert_quoted(&1, quoted)
   end
 
   defp insert_quoted(other, _quoted) do
     other
   end
-
-  defp column(column, mark) do
-    # length('<%') == 2
-    column + 2 + length(mark)
-  end
 end

lib/eex/lib/eex/engine.ex

@@ -2,73 +2,37 @@ defmodule EEx.Engine do
   @moduledoc ~S"""
   Basic EEx engine that ships with Elixir.
 
-  An engine needs to implement all callbacks below.
+  An engine needs to implement four functions:
 
-  This module also ships with a default engine implementation
-  you can delegate to. See `EEx.SmartEngine` as an example.
+    * `init(opts)` - returns the initial buffer
+
+    * `handle_body(quoted)` - receives the final built quoted
+      expression, should do final post-processing and return a
+      quoted expression.
+
+    * `handle_text(buffer, text)` - it receives the buffer,
+      the text and must return a new quoted expression.
+
+    * `handle_expr(buffer, marker, expr)` - it receives the buffer,
+      the marker, the expr and must return a new quoted expression.
+
+      The marker is what follows exactly after `<%`. For example,
+      `<% foo %>` has an empty marker, but `<%= foo %>` has `"="`
+      as marker. The allowed markers so far are: `""` and `"="`.
+
+      Read `handle_expr/3` below for more information about the markers
+      implemented by default by this engine.
+
+  `EEx.Engine` can be used directly if one desires to use the
+  default implementations for the functions above.
   """
 
-  @type state :: term
-
-  @doc """
-  Called at the beginning of every template.
-
-  It must return the initial state.
-  """
-  @callback init(opts :: keyword) :: state
-
-  @doc """
-  Called at the end of every template.
-
-  It must return Elixir's quoted expressions for the template.
-  """
-  @callback handle_body(state) :: Macro.t()
-
-  @doc """
-  Called for the text/static parts of a template.
-
-  It must return the updated state.
-  """
-  @callback handle_text(state, [line: pos_integer, column: pos_integer], text :: String.t()) ::
-              state
-
-  @doc """
-  Called for the dynamic/code parts of a template.
-
-  The marker is what follows exactly after `<%`. For example,
-  `<% foo %>` has an empty marker, but `<%= foo %>` has `"="`
-  as marker. The allowed markers so far are:
-
-    * `""`
-    * `"="`
-    * `"/"`
-    * `"|"`
-
-  Markers `"/"` and `"|"` are only for use in custom EEx engines
-  and are not implemented by default. Using them without an
-  appropriate implementation raises `EEx.SyntaxError`.
-
-  It must return the updated state.
-  """
-  @callback handle_expr(state, marker :: String.t(), expr :: Macro.t()) :: state
-
-  @doc """
-  Invoked at the beginning of every nesting.
-
-  It must return a new state that is used only inside the nesting.
-  Once the nesting terminates, the current `state` is resumed.
-  """
-  @callback handle_begin(state) :: state
-
-  @doc """
-  Invokes at the end of a nesting.
-
-  It must return Elixir's quoted expressions for the nesting.
-  """
-  @callback handle_end(state) :: Macro.t()
+  @callback init(opts :: Keyword.t) :: Macro.t
+  @callback handle_body(quoted :: Macro.t) :: Macro.t
+  @callback handle_text(buffer :: Macro.t, text :: String.t) :: Macro.t
+  @callback handle_expr(buffer :: Macro.t, marker :: String.t, expr :: Macro.t) :: Macro.t
 
   @doc false
-  @deprecated "Use explicit delegation to EEx.Engine instead"
   defmacro __using__(_) do
     quote do
       @behaviour EEx.Engine
@@ -77,27 +41,19 @@ defmodule EEx.Engine do
         EEx.Engine.init(opts)
       end
 
-      def handle_body(state) do
-        EEx.Engine.handle_body(state)
+      def handle_body(quoted) do
+        EEx.Engine.handle_body(quoted)
       end
 
-      def handle_begin(state) do
-        EEx.Engine.handle_begin(state)
+      def handle_text(buffer, text) do
+        EEx.Engine.handle_text(buffer, text)
       end
 
-      def handle_end(state) do
-        EEx.Engine.handle_end(state)
+      def handle_expr(buffer, marker, expr) do
+        EEx.Engine.handle_expr(buffer, marker, expr)
       end
 
-      def handle_text(state, text) do
-        EEx.Engine.handle_text(state, [], text)
-      end
-
-      def handle_expr(state, marker, expr) do
-        EEx.Engine.handle_expr(state, marker, expr)
-      end
-
-      defoverridable EEx.Engine
+      defoverridable [handle_body: 1, handle_expr: 3, handle_text: 2, init: 1]
     end
   end
 
@@ -110,112 +66,78 @@ defmodule EEx.Engine do
   This can be added to any custom engine by invoking
   `handle_assign/1` with `Macro.prewalk/2`:
 
-      def handle_expr(state, token, expr) do
+      def handle_expr(buffer, token, expr) do
         expr = Macro.prewalk(expr, &EEx.Engine.handle_assign/1)
-        super(state, token, expr)
+        EEx.Engine.handle_expr(buffer, token, expr)
       end
 
   """
-  @spec handle_assign(Macro.t()) :: Macro.t()
+  @spec handle_assign(Macro.t) :: Macro.t
   def handle_assign({:@, meta, [{name, _, atom}]}) when is_atom(name) and is_atom(atom) do
     line = meta[:line] || 0
-    quote(line: line, do: EEx.Engine.fetch_assign!(var!(assigns), unquote(name)))
+    quote line: line, do: EEx.Engine.fetch_assign!(var!(assigns), unquote(name))
   end
-
   def handle_assign(arg) do
     arg
   end
 
   @doc false
-  # TODO: Raise on v2.0
-  @spec fetch_assign!(Access.t(), Access.key()) :: term | nil
+  # TODO: Raise on 2.0
+  @spec fetch_assign!(map, Map.key) :: term | nil
   def fetch_assign!(assigns, key) do
     case Access.fetch(assigns, key) do
       {:ok, val} ->
         val
-
       :error ->
         keys = Enum.map(assigns, &elem(&1, 0))
-
-        IO.warn(
-          "assign @#{key} not available in EEx template. " <>
-            "Please ensure all assigns are given as options. " <>
-            "Available assigns: #{inspect(keys)}"
-        )
-
+        IO.warn "assign @#{key} not available in EEx template. " <>
+                "Please ensure all assigns are given as options. " <>
+                "Available assigns: #{inspect keys}"
         nil
     end
   end
 
-  @doc "Default implementation for `c:init/1`."
+  @doc """
+  Returns an empty string as initial buffer.
+  """
   def init(_opts) do
-    %{
-      binary: [],
-      dynamic: [],
-      vars_count: 0
-    }
+    ""
   end
 
-  @doc "Default implementation for `c:handle_begin/1`."
-  def handle_begin(state) do
-    check_state!(state)
-    %{state | binary: [], dynamic: []}
+  @doc """
+  The default implementation simply returns the given expression.
+  """
+  def handle_body(quoted) do
+    quoted
   end
 
-  @doc "Default implementation for `c:handle_end/1`."
-  def handle_end(quoted) do
-    handle_body(quoted)
+  @doc """
+  The default implementation simply concatenates text to the buffer.
+  """
+  def handle_text(buffer, text) do
+    quote do: unquote(buffer) <> unquote(text)
   end
 
-  @doc "Default implementation for `c:handle_body/1`."
-  def handle_body(state) do
-    check_state!(state)
-    %{binary: binary, dynamic: dynamic} = state
-    binary = {:<<>>, [], Enum.reverse(binary)}
-    dynamic = [binary | dynamic]
-    {:__block__, [], Enum.reverse(dynamic)}
+  @doc """
+  Implements expressions according to the markers.
+
+      <% Elixir expression - inline with output %>
+      <%= Elixir expression - replace with result %>
+
+  All other markers are not implemented by this engine.
+  """
+  def handle_expr(buffer, "=", expr) do
+    quote do
+      tmp1 = unquote(buffer)
+      tmp1 <> String.Chars.to_string(unquote(expr))
+    end
   end
 
-  @doc "Default implementation for `c:handle_text/3`."
-  def handle_text(state, _meta, text) do
-    check_state!(state)
-    %{binary: binary} = state
-    %{state | binary: [text | binary]}
-  end
-
-  @doc "Default implementation for `c:handle_expr/3`."
-  def handle_expr(state, "=", ast) do
-    check_state!(state)
-    %{binary: binary, dynamic: dynamic, vars_count: vars_count} = state
-    var = Macro.var(:"arg#{vars_count}", __MODULE__)
-
-    ast =
-      quote do
-        unquote(var) = String.Chars.to_string(unquote(ast))
-      end
-
-    segment =
-      quote do
-        unquote(var) :: binary
-      end
-
-    %{state | dynamic: [ast | dynamic], binary: [segment | binary], vars_count: vars_count + 1}
-  end
-
-  def handle_expr(state, "", ast) do
-    %{dynamic: dynamic} = state
-    %{state | dynamic: [ast | dynamic]}
-  end
-
-  def handle_expr(_state, marker, _ast) when marker in ["/", "|"] do
-    raise EEx.SyntaxError,
-          "unsupported EEx syntax <%#{marker} %> (the syntax is valid but not supported by the current EEx engine)"
-  end
-
-  defp check_state!(%{binary: _, dynamic: _, vars_count: _}), do: :ok
-
-  defp check_state!(state) do
-    raise "unexpected EEx.Engine state: #{inspect(state)}. " <>
-            "This typically means a bug or an outdated EEx.Engine or tool"
+  def handle_expr(buffer, "", expr) do
+    quote do
+      tmp2 = unquote(buffer)
+      unquote(expr)
+      tmp2
+    end
   end
 end

lib/eex/lib/eex/smart_engine.ex

@@ -24,35 +24,18 @@ defmodule EEx.SmartEngine do
       # sample.ex
       defmodule Sample do
         require EEx
-        EEx.function_from_file(:def, :sample, "sample.eex", [:assigns])
+        EEx.function_from_file :def, :sample, "sample.eex", [:assigns]
       end
 
       # iex
-      Sample.sample(a: 1, b: 2)
-      #=> "3"
+      Sample.sample(a: 1, b: 2) #=> "3"
 
   """
 
-  @behaviour EEx.Engine
+  use EEx.Engine
 
-  @impl true
-  defdelegate init(opts), to: EEx.Engine
-
-  @impl true
-  defdelegate handle_body(state), to: EEx.Engine
-
-  @impl true
-  defdelegate handle_begin(state), to: EEx.Engine
-
-  @impl true
-  defdelegate handle_end(state), to: EEx.Engine
-
-  @impl true
-  defdelegate handle_text(state, meta, text), to: EEx.Engine
-
-  @impl true
-  def handle_expr(state, marker, expr) do
+  def handle_expr(buffer, mark, expr) do
     expr = Macro.prewalk(expr, &EEx.Engine.handle_assign/1)
-    EEx.Engine.handle_expr(state, marker, expr)
+    super(buffer, mark, expr)
   end
 end

lib/eex/lib/eex/tokenizer.ex

@@ -1,113 +1,80 @@
 defmodule EEx.Tokenizer do
   @moduledoc false
 
-  @type content :: IO.chardata()
+  @type content :: IO.chardata
   @type line :: non_neg_integer
-  @type column :: non_neg_integer
-  @type marker :: '=' | '/' | '|' | ''
-  @type token ::
-          {:text, line, column, content}
-          | {:expr | :start_expr | :middle_expr | :end_expr, line, column, marker, content}
-          | {:eof, line, column}
-
-  @spaces [?\s, ?\t]
+  @type token :: {:text, content} |
+                 {:expr | :start_expr | :middle_expr | :end_expr, line, '=' | '', content}
 
   @doc """
   Tokenizes the given charlist or binary.
 
   It returns {:ok, list} with the following tokens:
 
-    * `{:text, line, column, content}`
-    * `{:expr, line, column, marker, content}`
-    * `{:start_expr, line, column, marker, content}`
-    * `{:middle_expr, line, column, marker, content}`
-    * `{:end_expr, line, column, marker, content}`
-    * `{:eof, line, column}`
+    * `{:text, content}`
+    * `{:expr, line, marker, content}`
+    * `{:start_expr, line, marker, content}`
+    * `{:middle_expr, line, marker, content}`
+    * `{:end_expr, line, marker, content}`
 
-  Or `{:error, line, column, message}` in case of errors.
+  Or `{:error, line, error}` in case of errors.
   """
-  @spec tokenize(binary | charlist, line, column, map) ::
-          {:ok, [token]} | {:error, line, column, String.t()}
+  @spec tokenize(binary | charlist, line, Keyword.t) :: {:ok, [token]} | {:error, line, String.t}
+  def tokenize(bin, line, opts \\ [])
 
-  def tokenize(bin, line, column, opts) when is_binary(bin) do
-    tokenize(String.to_charlist(bin), line, column, opts)
+  def tokenize(bin, line, opts)
+      when is_binary(bin) and is_integer(line) and line >= 0 and is_list(opts) do
+    tokenize(String.to_charlist(bin), line, opts)
   end
 
-  def tokenize(list, line, column, opts)
-      when is_list(list) and is_integer(line) and line >= 0 and is_integer(column) and column >= 0 do
-    column = opts.indentation + column
-
-    {list, line, column} =
-      (opts.trim && trim_init(list, line, column, opts)) || {list, line, column}
-
-    tokenize(list, line, column, opts, [{line, column}], [])
+  def tokenize(list, line, opts)
+      when is_list(list) and is_integer(line) and line >= 0 and is_list(opts) do
+    tokenize(list, line, opts, [], [])
   end
 
-  defp tokenize('<%%' ++ t, line, column, opts, buffer, acc) do
-    tokenize(t, line, column + 3, opts, [?%, ?< | buffer], acc)
+  defp tokenize('<%%' ++ t, line, opts, buffer, acc) do
+   tokenize t, line, opts, [?%, ?< | buffer], acc
   end
 
-  defp tokenize('<%#' ++ t, line, column, opts, buffer, acc) do
-    case expr(t, line, column + 3, opts, []) do
-      {:error, _, _, _} = error ->
-        error
-
-      {:ok, _, new_line, new_column, rest} ->
-        {rest, new_line, new_column, buffer} =
-          trim_if_needed(rest, new_line, new_column, opts, buffer)
-
-        acc = tokenize_text(buffer, acc)
-        tokenize(rest, new_line, new_column, opts, [{new_line, new_column}], acc)
+  defp tokenize('<%#' ++ t, line, opts, buffer, acc) do
+    case expr(t, line, []) do
+      {:error, _, _} = error -> error
+      {:ok, _, new_line, rest} ->
+        {rest, new_line, buffer} = trim_if_needed(rest, new_line, opts, buffer, acc)
+        tokenize rest, new_line, opts, buffer, acc
     end
   end
 
-  defp tokenize('<%' ++ t, line, column, opts, buffer, acc) do
+  defp tokenize('<%' ++ t, line, opts, buffer, acc) do
     {marker, t} = retrieve_marker(t)
 
-    case expr(t, line, column + 2 + length(marker), opts, []) do
-      {:error, _, _, _} = error ->
-        error
-
-      {:ok, expr, new_line, new_column, rest} ->
-        {key, expr} =
-          case :elixir_tokenizer.tokenize(expr, 1, file: "eex", check_terminators: false) do
-            {:ok, _line, _column, warnings, tokens} ->
-              Enum.each(Enum.reverse(warnings), fn {location, file, msg} ->
-                :elixir_errors.erl_warn(location, file, msg)
-              end)
-
-              token_key(tokens, expr)
-
-            {:error, _, _, _, _} ->
-              {:expr, expr}
-          end
-
-        {rest, new_line, new_column, buffer} =
-          trim_if_needed(rest, new_line, new_column, opts, buffer)
-
-        acc = tokenize_text(buffer, acc)
-        final = {key, line, column, marker, expr}
-        tokenize(rest, new_line, new_column, opts, [{new_line, new_column}], [final | acc])
+    case expr(t, line, []) do
+      {:error, _, _} = error -> error
+      {:ok, expr, new_line, rest} ->
+        token = token_name(expr)
+        {rest, new_line, buffer} = trim_if_needed(rest, new_line, opts, buffer, acc)
+        acc   = tokenize_text(buffer, acc)
+        final = {token, line, marker, Enum.reverse(expr)}
+        tokenize rest, new_line, opts, [], [final | acc]
     end
   end
 
-  defp tokenize('\n' ++ t, line, _column, opts, buffer, acc) do
-    tokenize(t, line + 1, opts.indentation + 1, opts, [?\n | buffer], acc)
+  defp tokenize('\n' ++ t, line, opts, buffer, acc) do
+    tokenize t, line + 1, opts, [?\n | buffer], acc
   end
 
-  defp tokenize([h | t], line, column, opts, buffer, acc) do
-    tokenize(t, line, column + 1, opts, [h | buffer], acc)
+  defp tokenize([h | t], line, opts, buffer, acc) do
+    tokenize t, line, opts, [h | buffer], acc
   end
 
-  defp tokenize([], line, column, _opts, buffer, acc) do
-    eof = {:eof, line, column}
-    {:ok, Enum.reverse([eof | tokenize_text(buffer, acc)])}
+  defp tokenize([], _line, _opts, buffer, acc) do
+    {:ok, Enum.reverse(tokenize_text(buffer, acc))}
   end
 
   # Retrieve marker for <%
 
-  defp retrieve_marker([marker | t]) when marker in [?=, ?/, ?|] do
-    {[marker], t}
+  defp retrieve_marker('=' ++ t) do
+    {'=', t}
   end
 
   defp retrieve_marker(t) do
@@ -116,129 +83,140 @@ defmodule EEx.Tokenizer do
 
   # Tokenize an expression until we find %>
 
-  defp expr([?%, ?> | t], line, column, _opts, buffer) do
-    {:ok, Enum.reverse(buffer), line, column + 2, t}
+  defp expr([?%, ?> | t], line, buffer) do
+    {:ok, buffer, line, t}
   end
 
-  defp expr('\n' ++ t, line, _column, opts, buffer) do
-    expr(t, line + 1, opts.indentation + 1, opts, [?\n | buffer])
+  defp expr('\n' ++ t, line, buffer) do
+    expr t, line + 1, [?\n | buffer]
   end
 
-  defp expr([h | t], line, column, opts, buffer) do
-    expr(t, line, column + 1, opts, [h | buffer])
+  defp expr([h | t], line, buffer) do
+    expr t, line, [h | buffer]
   end
 
-  defp expr([], line, column, _opts, _buffer) do
-    {:error, line, column, "missing token '%>'"}
+  defp expr([], line, _buffer) do
+    {:error, line, "missing token '%>'"}
   end
 
-  # Receives tokens and check if it is a start, middle or an end token.
-  defp token_key(tokens, expr) do
-    case {tokens, tokens |> Enum.reverse() |> drop_eol()} do
-      {[{:end, _} | _], [{:do, _} | _]} ->
-        {:middle_expr, expr}
+  # Receive an expression content and check
+  # if it is a start, middle or an end token.
+  #
+  # Start tokens finish with "do" and "fn ->"
+  # Middle tokens are marked with "->" or keywords
+  # End tokens contain only the end word and optionally ")"
 
-      {_, [{:do, _} | _]} ->
-        {:start_expr, maybe_append_space(expr)}
+  defp token_name([h | t]) when h in [?\s, ?\t, ?)] do
+    token_name(t)
+  end
 
-      {_, [{:block_identifier, _, _} | _]} ->
-        {:middle_expr, maybe_append_space(expr)}
+  defp token_name('od' ++ [h | _]) when h in [?\s, ?\t, ?)] do
+    :start_expr
+  end
 
-      {[{:end, _} | _], [{:stab_op, _, _} | _]} ->
-        {:middle_expr, expr}
+  defp token_name('>-' ++ rest) do
+    rest = Enum.reverse(rest)
 
-      {_, [{:stab_op, _, _} | reverse_tokens]} ->
-        fn_index = Enum.find_index(reverse_tokens, &match?({:fn, _}, &1)) || :infinity
-        end_index = Enum.find_index(reverse_tokens, &match?({:end, _}, &1)) || :infinity
+    # Tokenize the remaining passing check_terminators as
+    # false, which relax the tokenizer to not error on
+    # unmatched pairs. Then, we check if there is a "fn"
+    # token and, if so, it is not followed by an "end"
+    # token. If this is the case, we are on a start expr.
+    case :elixir_tokenizer.tokenize(rest, 1, file: "eex", check_terminators: false) do
+      {:ok, _line, _column, tokens} ->
+        tokens   = Enum.reverse(tokens)
+        fn_index = fn_index(tokens)
 
-        if end_index > fn_index do
-          {:start_expr, expr}
+        if fn_index && end_index(tokens) > fn_index do
+          :start_expr
         else
-          {:middle_expr, expr}
-        end
-
-      {tokens, _} ->
-        case Enum.drop_while(tokens, &closing_bracket?/1) do
-          [{:end, _} | _] -> {:end_expr, expr}
-          _ -> {:expr, expr}
+          :middle_expr
         end
+      _error ->
+        :middle_expr
     end
   end
 
-  defp drop_eol([{:eol, _} | rest]), do: drop_eol(rest)
-  defp drop_eol(rest), do: rest
+  defp token_name('esle' ++ t),   do: check_spaces(t, :middle_expr)
+  defp token_name('retfa' ++ t),  do: check_spaces(t, :middle_expr)
+  defp token_name('hctac' ++ t),  do: check_spaces(t, :middle_expr)
+  defp token_name('eucser' ++ t), do: check_spaces(t, :middle_expr)
+  defp token_name('dne' ++ t),    do: check_spaces(t, :end_expr)
 
-  defp maybe_append_space([?\s]), do: [?\s]
-  defp maybe_append_space([h]), do: [h, ?\s]
-  defp maybe_append_space([h | t]), do: [h | maybe_append_space(t)]
+  defp token_name(_) do
+    :expr
+  end
 
-  defp closing_bracket?({closing, _}) when closing in ~w"( [ {"a, do: true
-  defp closing_bracket?(_), do: false
+  defp fn_index(tokens) do
+    Enum.find_index tokens, fn
+      {:fn_paren, _} -> true
+      {:fn, _}       -> true
+      _              -> false
+    end
+  end
+
+  defp end_index(tokens) do
+    Enum.find_index(tokens, &match?({:end, _}, &1)) || :infinity
+  end
+
+  defp check_spaces(string, token) do
+    if Enum.all?(string, &(&1 in [?\s, ?\t])) do
+      token
+    else
+      :expr
+    end
+  end
 
   # Tokenize the buffered text by appending
   # it to the given accumulator.
 
-  defp tokenize_text([{_line, _column}], acc) do
+  defp tokenize_text([], acc) do
     acc
   end
 
   defp tokenize_text(buffer, acc) do
-    [{line, column} | buffer] = Enum.reverse(buffer)
-    [{:text, line, column, buffer} | acc]
+    [{:text, Enum.reverse(buffer)} | acc]
   end
 
-  defp trim_if_needed(rest, line, column, opts, buffer) do
-    if opts.trim do
-      buffer = trim_left(buffer, 0)
-      {rest, line, column} = trim_right(rest, line, column, 0, opts)
-      {rest, line, column, buffer}
+  # If trim mode is enabled and the token is on a line with
+  # only itself and whitespace, trim the whitespace around it,
+  # including the line break following it if there is one.
+  defp trim_if_needed(rest, line, opts, buffer, acc) do
+    original = {rest, line, buffer}
+    if opts[:trim] do
+      case {trim_left(buffer, acc), trim_right(rest, line)} do
+        {{true, new_buffer}, {true, new_rest, new_line}} ->
+          {new_rest, new_line, new_buffer}
+        _ ->
+          original
+      end
     else
-      {rest, line, column, buffer}
+      original
     end
   end
 
-  defp trim_init([h | t], line, column, opts) when h in @spaces,
-    do: trim_init(t, line, column + 1, opts)
-
-  defp trim_init([?\r, ?\n | t], line, _column, opts),
-    do: trim_init(t, line + 1, opts.indentation + 1, opts)
-
-  defp trim_init([?\n | t], line, _column, opts),
-    do: trim_init(t, line + 1, opts.indentation + 1, opts)
-
-  defp trim_init([?<, ?% | _] = rest, line, column, _opts),
-    do: {rest, line, column}
-
-  defp trim_init(_, _, _, _), do: false
-
-  defp trim_left(buffer, count) do
-    case trim_whitespace(buffer, 0) do
-      {[?\n, ?\r | rest], _} -> trim_left(rest, count + 1)
-      {[?\n | rest], _} -> trim_left(rest, count + 1)
-      _ when count > 0 -> [?\n | buffer]
-      _ -> buffer
+  defp trim_left(buffer, acc) do
+    case {trim_whitespace(buffer), acc} do
+      {[?\n | _] = trimmed_buffer, _} -> {true, trimmed_buffer}
+      {[], []} -> {true, []}
+      _ -> {false, buffer}
     end
   end
 
-  defp trim_right(rest, line, column, last_column, opts) do
-    case trim_whitespace(rest, column) do
-      {[?\r, ?\n | rest], column} ->
-        trim_right(rest, line + 1, opts.indentation + 1, column + 1, opts)
-
-      {[?\n | rest], column} ->
-        trim_right(rest, line + 1, opts.indentation + 1, column, opts)
-
-      {[], column} ->
-        {[], line, column}
-
-      _ when last_column > 0 ->
-        {[?\n | rest], line - 1, last_column}
-
-      _ ->
-        {rest, line, column}
+  defp trim_right(rest, line) do
+    case trim_whitespace(rest) do
+      [?\r, ?\n | trimmed_rest] -> {true, trimmed_rest, line + 1}
+      [?\n | trimmed_rest] -> {true, trimmed_rest, line + 1}
+      [] -> {true, [], line}
+      _ -> {false, rest, line}
     end
   end
 
-  defp trim_whitespace([h | t], column) when h in @spaces, do: trim_whitespace(t, column + 1)
-  defp trim_whitespace(list, column), do: {list, column}
+  defp trim_whitespace([h | t]) when h == ?\s or h == ?\t do
+    trim_whitespace(t)
+  end
+
+  defp trim_whitespace(list) do
+    list
+  end
 end

lib/eex/mix.exs

@@ -1,11 +1,9 @@
-defmodule EEx.MixProject do
+defmodule EEx.Mixfile do
   use Mix.Project
 
   def project do
-    [
-      app: :eex,
-      version: System.version(),
-      build_per_environment: false
-    ]
+    [app: :eex,
+     version: System.version,
+     build_per_environment: false]
   end
 end

lib/eex/test/eex/smart_engine_test.exs

@@ -1,59 +1,45 @@
-Code.require_file("../test_helper.exs", __DIR__)
+Code.require_file "../test_helper.exs", __DIR__
 
 defmodule EEx.SmartEngineTest do
   use ExUnit.Case, async: true
 
+  import ExUnit.CaptureIO
+
   test "evaluates simple string" do
-    assert_eval("foo bar", "foo bar")
+    assert_eval "foo bar", "foo bar"
   end
 
   test "evaluates with assigns as keywords" do
-    assert_eval("1", "<%= @foo %>", assigns: [foo: 1])
+    assert_eval "1", "<%= @foo %>", assigns: [foo: 1]
   end
 
   test "evaluates with assigns as a map" do
-    assert_eval("1", "<%= @foo %>", assigns: %{foo: 1})
+    assert_eval "1", "<%= @foo %>", assigns: %{foo: 1}
   end
 
   test "error with missing assigns" do
-    stderr =
-      ExUnit.CaptureIO.capture_io(:stderr, fn ->
-        assert_eval("", "<%= @foo %>", assigns: %{})
-      end)
-
+    stderr = capture_io(:stderr, fn ->
+      assert_eval "", "<%= @foo %>", assigns: %{}
+    end)
     assert stderr =~ "assign @foo not available in EEx template"
   end
 
   test "evaluates with loops" do
-    assert_eval("1\n2\n3\n", "<%= for x <- [1, 2, 3] do %><%= x %>\n<% end %>")
+    assert_eval "1\n2\n3\n", "<%= for x <- [1, 2, 3] do %><%= x %>\n<% end %>"
   end
 
-  test "preserves line numbers in assignments" do
-    result = EEx.compile_string("foo\n<%= @hello %>", engine: EEx.SmartEngine)
-
+  test "compiled preserved line numbers" do
+    result = EEx.compile_string("<%= @hello %>", engine: EEx.SmartEngine)
     Macro.prewalk(result, fn
-      {_left, meta, [_, :hello]} ->
-        assert Keyword.get(meta, :line) == 2
-        send(self(), :found)
-
-      node ->
-        node
+      {_left, meta, _right} ->
+        assert Keyword.get(meta, :line, 0) in [0, 1]
+      _ ->
+        :ok
     end)
-
-    assert_received :found
-  end
-
-  test "error with unused \"do\" block without \"<%=\" modifier" do
-    stderr =
-      ExUnit.CaptureIO.capture_io(:stderr, fn ->
-        assert_eval("", "<% if true do %>I'm invisible!<% end %>", assigns: %{})
-      end)
-
-    assert stderr =~ "the contents of this expression won't be output"
   end
 
   defp assert_eval(expected, actual, binding \\ []) do
-    result = EEx.eval_string(actual, binding, file: __ENV__.file, engine: EEx.SmartEngine)
+    result = EEx.eval_string(actual, binding, file: __ENV__.file)
     assert result == expected
   end
 end

lib/eex/test/eex/tokenizer_test.exs

@@ -1,291 +1,154 @@
-Code.require_file("../test_helper.exs", __DIR__)
+Code.require_file "../test_helper.exs", __DIR__
 
 defmodule EEx.TokenizerTest do
   use ExUnit.Case, async: true
   require EEx.Tokenizer, as: T
 
-  @opts %{indentation: 0, trim: false}
-
   test "simple chars lists" do
-    assert T.tokenize('foo', 1, 1, @opts) == {:ok, [{:text, 1, 1, 'foo'}, {:eof, 1, 4}]}
+    assert T.tokenize('foo', 1) == {:ok, [{:text, 'foo'}]}
   end
 
   test "simple strings" do
-    assert T.tokenize("foo", 1, 1, @opts) == {:ok, [{:text, 1, 1, 'foo'}, {:eof, 1, 4}]}
+    assert T.tokenize("foo", 1) == {:ok, [{:text, 'foo'}]}
   end
 
   test "strings with embedded code" do
-    assert T.tokenize('foo <% bar %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo '}, {:expr, 1, 5, '', ' bar '}, {:eof, 1, 14}]}
+    assert T.tokenize('foo <% bar %>', 1) ==
+           {:ok, [{:text, 'foo '}, {:expr, 1, '', ' bar '}]}
   end
 
   test "strings with embedded equals code" do
-    assert T.tokenize('foo <%= bar %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo '}, {:expr, 1, 5, '=', ' bar '}, {:eof, 1, 15}]}
-  end
-
-  test "strings with embedded slash code" do
-    assert T.tokenize('foo <%/ bar %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo '}, {:expr, 1, 5, '/', ' bar '}, {:eof, 1, 15}]}
-  end
-
-  test "strings with embedded pipe code" do
-    assert T.tokenize('foo <%| bar %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo '}, {:expr, 1, 5, '|', ' bar '}, {:eof, 1, 15}]}
+    assert T.tokenize('foo <%= bar %>', 1) ==
+           {:ok, [{:text, 'foo '}, {:expr, 1, '=', ' bar '}]}
   end
 
   test "strings with more than one line" do
-    assert T.tokenize('foo\n<%= bar %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo\n'}, {:expr, 2, 1, '=', ' bar '}, {:eof, 2, 11}]}
+    assert T.tokenize('foo\n<%= bar %>', 1) ==
+           {:ok, [{:text, 'foo\n'}, {:expr, 2, '=', ' bar '}]}
   end
 
   test "strings with more than one line and expression with more than one line" do
     string = '''
-    foo <%= bar
+foo <%= bar
 
-    baz %>
-    <% foo %>
-    '''
+baz %>
+<% foo %>
+'''
 
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:expr, 1, 5, '=', ' bar\n\nbaz '},
-      {:text, 3, 7, '\n'},
-      {:expr, 4, 1, '', ' foo '},
-      {:text, 4, 10, '\n'},
-      {:eof, 5, 1}
-    ]
-
-    assert T.tokenize(string, 1, 1, @opts) == {:ok, exprs}
+    assert T.tokenize(string, 1) == {:ok, [
+      {:text, 'foo '},
+      {:expr, 1, '=', ' bar\n\nbaz '},
+      {:text, '\n'},
+      {:expr, 4, '', ' foo '},
+      {:text, '\n'}
+    ]}
   end
 
   test "quotation" do
-    assert T.tokenize('foo <%% true %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo <% true %>'}, {:eof, 1, 16}]}
+    assert T.tokenize('foo <%% true %>', 1) == {:ok, [
+      {:text, 'foo <% true %>'}
+    ]}
   end
 
-  test "quotation with do-end" do
-    assert T.tokenize('foo <%% true do %>bar<%% end %>', 1, 1, @opts) ==
-             {:ok, [{:text, 1, 1, 'foo <% true do %>bar<% end %>'}, {:eof, 1, 32}]}
+  test "quotation with do/end" do
+    assert T.tokenize('foo <%% true do %>bar<%% end %>', 1) == {:ok, [
+      {:text, 'foo <% true do %>bar<% end %>'}
+    ]}
   end
 
   test "quotation with interpolation" do
-    exprs = [
-      {:text, 1, 1, 'a <% b '},
-      {:expr, 1, 9, '=', ' c '},
-      {:text, 1, 17, ' '},
-      {:expr, 1, 18, '=', ' d '},
-      {:text, 1, 26, ' e %> f'},
-      {:eof, 1, 33}
-    ]
+    assert T.tokenize('a <%% b <%= c %> <%= d %> e %> f', 1) == {:ok, [
+      {:text, 'a <% b '},
+      {:expr, 1, '=', ' c '},
+      {:text, ' '},
+      {:expr, 1, '=', ' d '},
+      {:text, ' e %> f'}
+    ]}
 
-    assert T.tokenize('a <%% b <%= c %> <%= d %> e %> f', 1, 1, @opts) == {:ok, exprs}
+    assert T.tokenize('<%%% a <%%= b %> c %>', 1) == {:ok, [
+      {:text, '<%% a <%= b %> c %>'}
+    ]}
   end
 
-  test "improperly formatted quotation with interpolation" do
-    exprs = [
-      {:text, 1, 1, '<%% a <%= b %> c %>'},
-      {:eof, 1, 22}
-    ]
-
-    assert T.tokenize('<%%% a <%%= b %> c %>', 1, 1, @opts) == {:ok, exprs}
+  test "comments" do
+    assert T.tokenize('foo <%# true %>', 1) == {:ok, [
+      {:text, 'foo '}
+    ]}
   end
 
-  test "EEx comments" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:eof, 1, 16}
-    ]
-
-    assert T.tokenize('foo <%# true %>', 1, 1, @opts) == {:ok, exprs}
-  end
-
-  test "EEx comments with do-end" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:text, 1, 19, 'bar'},
-      {:eof, 1, 32}
-    ]
-
-    assert T.tokenize('foo <%# true do %>bar<%# end %>', 1, 1, @opts) == {:ok, exprs}
-  end
-
-  test "EEx comments inside do-end" do
-    exprs = [
-      {:start_expr, 1, 1, '', ' if true do '},
-      {:text, 1, 31, 'bar'},
-      {:end_expr, 1, 34, [], ' end '},
-      {:eof, 1, 43}
-    ]
-
-    assert T.tokenize('<% if true do %><%# comment %>bar<% end %>', 1, 1, @opts) == {:ok, exprs}
-
-    exprs = [
-      {:start_expr, 1, 1, [], ' case true do '},
-      {:middle_expr, 1, 33, '', ' true -> '},
-      {:text, 1, 46, 'bar'},
-      {:end_expr, 1, 49, [], ' end '},
-      {:eof, 1, 58}
-    ]
-
-    assert T.tokenize('<% case true do %><%# comment %><% true -> %>bar<% end %>', 1, 1, @opts) ==
-             {:ok, exprs}
-  end
-
-  test "Elixir comments" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:expr, 1, 5, [], ' true # this is a boolean '},
-      {:eof, 1, 35}
-    ]
-
-    assert T.tokenize('foo <% true # this is a boolean %>', 1, 1, @opts) == {:ok, exprs}
-  end
-
-  test "Elixir comments with do-end" do
-    exprs = [
-      {:start_expr, 1, 1, [], ' if true do # startif '},
-      {:text, 1, 27, 'text'},
-      {:end_expr, 1, 31, [], ' end # closeif '},
-      {:eof, 1, 50}
-    ]
-
-    assert T.tokenize('<% if true do # startif %>text<% end # closeif %>', 1, 1, @opts) ==
-             {:ok, exprs}
+  test "comments with do/end" do
+    assert T.tokenize('foo <%# true do %>bar<%# end %>', 1) == {:ok, [
+      {:text, 'foo bar'}
+    ]}
   end
 
   test "strings with embedded do end" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:start_expr, 1, 5, '', ' if true do '},
-      {:text, 1, 21, 'bar'},
-      {:end_expr, 1, 24, '', ' end '},
-      {:eof, 1, 33}
-    ]
-
-    assert T.tokenize('foo <% if true do %>bar<% end %>', 1, 1, @opts) == {:ok, exprs}
+    assert T.tokenize('foo <% if true do %>bar<% end %>', 1) == {:ok, [
+      {:text, 'foo '},
+      {:start_expr, 1, '', ' if true do '},
+      {:text, 'bar'},
+      {:end_expr, 1, '', ' end '}
+    ]}
   end
 
   test "strings with embedded -> end" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:start_expr, 1, 5, '', ' cond do '},
-      {:middle_expr, 1, 18, '', ' false -> '},
-      {:text, 1, 32, 'bar'},
-      {:middle_expr, 1, 35, '', ' true -> '},
-      {:text, 1, 48, 'baz'},
-      {:end_expr, 1, 51, '', ' end '},
-      {:eof, 1, 60}
-    ]
-
-    assert T.tokenize('foo <% cond do %><% false -> %>bar<% true -> %>baz<% end %>', 1, 1, @opts) ==
-             {:ok, exprs}
-  end
-
-  test "strings with fn-end with newline" do
-    exprs = [
-      {:start_expr, 1, 1, '=', ' a fn ->\n'},
-      {:text, 2, 3, 'foo'},
-      {:end_expr, 2, 6, [], ' end '},
-      {:eof, 2, 15}
-    ]
-
-    assert T.tokenize('<%= a fn ->\n%>foo<% end %>', 1, 1, @opts) ==
-             {:ok, exprs}
-  end
-
-  test "strings with multiple fn-end" do
-    exprs = [
-      {:start_expr, 1, 1, '=', ' a fn -> '},
-      {:text, 1, 15, 'foo'},
-      {:middle_expr, 1, 18, '', ' end, fn -> '},
-      {:text, 1, 34, 'bar'},
-      {:end_expr, 1, 37, '', ' end '},
-      {:eof, 1, 46}
-    ]
-
-    assert T.tokenize('<%= a fn -> %>foo<% end, fn -> %>bar<% end %>', 1, 1, @opts) ==
-             {:ok, exprs}
-  end
-
-  test "strings with fn-end followed by do block" do
-    exprs = [
-      {:start_expr, 1, 1, '=', ' a fn -> '},
-      {:text, 1, 15, 'foo'},
-      {:middle_expr, 1, 18, '', ' end do '},
-      {:text, 1, 30, 'bar'},
-      {:end_expr, 1, 33, '', ' end '},
-      {:eof, 1, 42}
-    ]
-
-    assert T.tokenize('<%= a fn -> %>foo<% end do %>bar<% end %>', 1, 1, @opts) == {:ok, exprs}
+    assert T.tokenize('foo <% cond do %><% false -> %>bar<% true -> %>baz<% end %>', 1) == {:ok, [
+      {:text, 'foo '},
+      {:start_expr, 1, '', ' cond do '},
+      {:middle_expr, 1, '', ' false -> '},
+      {:text, 'bar'},
+      {:middle_expr, 1, '', ' true -> '},
+      {:text, 'baz'},
+      {:end_expr, 1, '', ' end '}
+    ]}
   end
 
   test "strings with embedded keywords blocks" do
-    exprs = [
-      {:text, 1, 1, 'foo '},
-      {:start_expr, 1, 5, '', ' if true do '},
-      {:text, 1, 21, 'bar'},
-      {:middle_expr, 1, 24, '', ' else '},
-      {:text, 1, 34, 'baz'},
-      {:end_expr, 1, 37, '', ' end '},
-      {:eof, 1, 46}
-    ]
-
-    assert T.tokenize('foo <% if true do %>bar<% else %>baz<% end %>', 1, 1, @opts) ==
-             {:ok, exprs}
+    assert T.tokenize('foo <% if true do %>bar<% else %>baz<% end %>', 1) == {:ok, [
+      {:text, 'foo '},
+      {:start_expr, 1, '', ' if true do '},
+      {:text, 'bar'},
+      {:middle_expr, 1, '', ' else '},
+      {:text, 'baz'},
+      {:end_expr, 1, '', ' end '}
+    ]}
   end
 
   test "trim mode" do
-    template = '\t<%= if true do %> \n TRUE \n  <% else %>\n FALSE \n  <% end %>  \n\n  '
-
-    exprs = [
-      {:start_expr, 1, 2, '=', ' if true do '},
-      {:text, 1, 20, '\n TRUE \n'},
-      {:middle_expr, 3, 3, '', ' else '},
-      {:text, 3, 13, '\n FALSE \n'},
-      {:end_expr, 5, 3, '', ' end '},
-      {:eof, 7, 3}
-    ]
-
-    assert T.tokenize(template, 1, 1, %{@opts | trim: true}) == {:ok, exprs}
+    template = '\t<%= if true do %> \n TRUE \n  <% else %>\n FALSE \n  <% end %>  '
+    assert T.tokenize(template, 1, trim: true) == {:ok, [
+      {:start_expr, 1, '=', ' if true do '},
+      {:text, ' TRUE \n'},
+      {:middle_expr, 3, '', ' else '},
+      {:text, ' FALSE \n'},
+      {:end_expr, 5, '', ' end '}
+    ]}
   end
 
   test "trim mode with comment" do
-    exprs = [
-      {:text, 1, 19, '\n123'},
-      {:eof, 2, 4}
-    ]
-
-    assert T.tokenize('  <%# comment %>  \n123', 1, 1, %{@opts | trim: true}) == {:ok, exprs}
+    assert T.tokenize('  <%# comment %>  \n123', 1, trim: true) == {:ok, [
+      {:text, '123'}
+    ]}
   end
 
   test "trim mode with CRLF" do
-    exprs = [
-      {:text, 1, 1, '0\n'},
-      {:expr, 2, 3, '=', ' 12 '},
-      {:text, 2, 15, '\n34'},
-      {:eof, 3, 3}
-    ]
-
-    assert T.tokenize('0\r\n  <%= 12 %>  \r\n34', 1, 1, %{@opts | trim: true}) == {:ok, exprs}
+    assert T.tokenize('0\r\n  <%= 12 %>  \r\n34', 1, trim: true) == {:ok, [
+      {:text, '0\r\n'},
+      {:expr, 2, '=', ' 12 '},
+      {:text, '34'}
+    ]}
   end
 
   test "trim mode set to false" do
-    exprs = [
-      {:text, 1, 1, ' '},
-      {:expr, 1, 2, '=', ' 12 '},
-      {:text, 1, 11, ' \n'},
-      {:eof, 2, 1}
-    ]
-
-    assert T.tokenize(' <%= 12 %> \n', 1, 1, %{@opts | trim: false}) == {:ok, exprs}
+    assert T.tokenize(' <%= 12 %> \n', 1, trim: false) == {:ok, [
+      {:text, ' '},
+      {:expr, 1, '=', ' 12 '},
+      {:text, ' \n'}
+    ]}
   end
 
   test "trim mode no false positives" do
-    assert_not_trimmed = fn x ->
-      assert T.tokenize(x, 1, 1, %{@opts | trim: false}) == T.tokenize(x, 1, 1, @opts)
-    end
+    assert_not_trimmed = fn x -> assert T.tokenize(x, 1, trim: true) == T.tokenize(x, 1) end
 
     assert_not_trimmed.('foo <%= "bar" %>  ')
     assert_not_trimmed.('\n  <%= "foo" %>bar')
@@ -293,13 +156,8 @@ defmodule EEx.TokenizerTest do
     assert_not_trimmed.('  <%= 01 %><%= 23 %>\n')
   end
 
-  test "returns error when there is start mark and no end mark" do
-    assert T.tokenize('foo <% :bar', 1, 1, @opts) == {:error, 1, 12, "missing token '%>'"}
-    assert T.tokenize('<%# true ', 1, 1, @opts) == {:error, 1, 10, "missing token '%>'"}
-  end
-
-  test "marks invalid expressions as regular expressions" do
-    assert T.tokenize('<% 1 $ 2 %>', 1, 1, @opts) ==
-             {:ok, [{:expr, 1, 1, [], ' 1 $ 2 '}, {:eof, 1, 12}]}
+  test "raise syntax error when there is start mark and no end mark" do
+    assert T.tokenize('foo <% :bar', 1) == {:error, 1, "missing token '%>'"}
+    assert T.tokenize('<%# true ', 1) == {:error, 1, "missing token '%>'"}
   end
 end

lib/eex/test/fixtures/eex_template_with_syntax_error.eex

@@ -1 +0,0 @@
-foo <%= bar

lib/eex/test/test_helper.exs

@@ -1 +1 @@
-ExUnit.start(trace: "--trace" in System.argv())
+ExUnit.start [trace: "--trace" in System.argv]

lib/elixir/diff.exs

@@ -1,156 +0,0 @@
-defmodule Diff do
-  @moduledoc """
-  Utilities for comparing build artifacts.
-  """
-
-  @known_chunks ~w(
-    abstract_code
-    debug_info
-    attributes
-    compile_info
-    exports
-    labeled_exports
-    imports
-    indexed_imports
-    locals
-    labeled_locals
-    atoms
-  )a
-
-  @doc """
-  Compares the build artifacts of two build directories.
-  """
-  @spec compare_dirs(Path.t(), Path.t()) ::
-          {
-            only1_paths :: list(Path.t()),
-            only2_paths :: list(Path.t()),
-            diff :: list({Path.t(), diff :: String.t()})
-          }
-  def compare_dirs(dir1, dir2) do
-    dir1 = Path.expand(dir1)
-    dir2 = Path.expand(dir2)
-
-    assert_dir!(dir1)
-    assert_dir!(dir2)
-
-    dir1_paths = relative_paths(dir1)
-    dir2_paths = relative_paths(dir2)
-
-    only1_paths = dir1_paths -- dir2_paths
-    only2_paths = dir2_paths -- dir1_paths
-    common_paths = dir1_paths -- only1_paths
-    common_files = Enum.reject(common_paths, &File.dir?/1)
-
-    diff =
-      Enum.flat_map(common_files, fn path ->
-        file1 = Path.join(dir1, path)
-        file2 = Path.join(dir2, path)
-
-        case compare_files(file1, file2) do
-          :eq -> []
-          {:diff, diff} -> [{path, diff}]
-        end
-      end)
-
-    {only1_paths, only2_paths, diff}
-  end
-
-  @doc """
-  Compares the contents of two files.
-
-  If the files are BEAM files, it performs a more human-friendly
-  "BEAM-diff".
-  """
-  @spec compare_files(Path.t(), Path.t()) :: :eq | {:diff, diff :: String.t()}
-  def compare_files(file1, file2) do
-    content1 = File.read!(file1)
-    content2 = File.read!(file2)
-
-    if content1 == content2 do
-      :eq
-    else
-      diff =
-        if String.ends_with?(file1, ".beam") do
-          beam_diff(file1, content1, file2, content2)
-        else
-          file_diff(file1, file2)
-        end
-
-      {:diff, diff}
-    end
-  end
-
-  defp beam_diff(file1, content1, file2, content2) do
-    with {:ok, {module, chunks1}} <- :beam_lib.chunks(content1, @known_chunks),
-         {:ok, {^module, chunks2}} <- :beam_lib.chunks(content2, @known_chunks),
-         true <- chunks1 != chunks2 do
-      for {chunk1, chunk2} <- Enum.zip(chunks1, chunks2), chunk1 != chunk2 do
-        tmp_file1 =
-          chunk1
-          |> inspect(pretty: true, limit: :infinity)
-          |> write_tmp()
-
-        tmp_file2 =
-          chunk2
-          |> inspect(pretty: true, limit: :infinity)
-          |> write_tmp()
-
-        file_diff(tmp_file1, tmp_file2)
-      end
-    else
-      _ ->
-        file_diff(file1, file2)
-    end
-  end
-
-  defp file_diff(file1, file2) do
-    {diff, _} = System.cmd("diff", [file1, file2])
-    diff
-  end
-
-  defp relative_paths(dir) do
-    dir
-    |> Path.join("**")
-    |> Path.wildcard()
-    |> Enum.map(&Path.relative_to(&1, dir))
-  end
-
-  defp assert_dir!(dir) do
-    unless File.dir?(dir) do
-      raise ArgumentError, "#{inspect(dir)} is not a directory"
-    end
-  end
-
-  defp write_tmp(content) do
-    filename = generate_tmp_filename()
-    File.mkdir_p!("tmp")
-    File.write!(Path.join("tmp", filename), content)
-    Path.join("tmp", filename)
-  end
-
-  defp generate_tmp_filename do
-    sec = :os.system_time(:second)
-    rand = :rand.uniform(999_999_999)
-    scheduler_id = :erlang.system_info(:scheduler_id)
-    "tmp-#{sec}-#{rand}-#{scheduler_id}"
-  end
-end
-
-case System.argv() do
-  [dir1, dir2] ->
-    case Diff.compare_dirs(dir1, dir2) do
-      {[], [], []} ->
-        IO.puts("#{inspect(dir1)} and #{inspect(dir2)} are equal")
-
-      {only1, only2, diff} ->
-        for path <- only1, do: IO.puts("Only in #{dir1}: #{path}")
-        for path <- only2, do: IO.puts("Only in #{dir2}: #{path}")
-        for {path, diff} <- diff, do: IO.puts("Diff #{path}:\n#{diff}")
-
-        System.halt(1)
-    end
-
-  _ ->
-    IO.puts("Please, provide two directories as arguments")
-    System.halt(1)
-end

lib/elixir/docs.exs

@@ -1,117 +0,0 @@
-# Returns config for Elixir docs
-
-canonical = System.fetch_env!("CANONICAL")
-
-[
-  extras: Path.wildcard("lib/elixir/pages/*.md") ++ ["CHANGELOG.md"],
-  deps: [
-    eex: "https://hexdocs.pm/eex/#{canonical}",
-    ex_unit: "https://hexdocs.pm/ex_unit/#{canonical}",
-    iex: "https://hexdocs.pm/iex/#{canonical}",
-    logger: "https://hexdocs.pm/logger/#{canonical}",
-    mix: "https://hexdocs.pm/mix/#{canonical}"
-  ],
-  groups_for_functions: [
-    Guards: &(&1[:guard] == true)
-  ],
-  skip_undefined_reference_warnings_on: ["lib/elixir/pages/compatibility-and-deprecations.md"],
-  groups_for_modules: [
-    # [Kernel, Kernel.SpecialForms],
-
-    "Basic Types": [
-      Atom,
-      Base,
-      Bitwise,
-      Date,
-      DateTime,
-      Exception,
-      Float,
-      Function,
-      Integer,
-      Module,
-      NaiveDateTime,
-      Record,
-      Regex,
-      String,
-      Time,
-      Tuple,
-      URI,
-      Version,
-      Version.Requirement
-    ],
-    "Collections & Enumerables": [
-      Access,
-      Date.Range,
-      Enum,
-      Keyword,
-      List,
-      Map,
-      MapSet,
-      Range,
-      Stream
-    ],
-    "IO & System": [
-      File,
-      File.Stat,
-      File.Stream,
-      IO,
-      IO.ANSI,
-      IO.Stream,
-      OptionParser,
-      Path,
-      Port,
-      StringIO,
-      System
-    ],
-    Calendar: [
-      Calendar,
-      Calendar.ISO,
-      Calendar.TimeZoneDatabase,
-      Calendar.UTCOnlyTimeZoneDatabase
-    ],
-    "Processes & Applications": [
-      Agent,
-      Application,
-      Config,
-      Config.Provider,
-      Config.Reader,
-      DynamicSupervisor,
-      GenServer,
-      Node,
-      Process,
-      Registry,
-      Supervisor,
-      Task,
-      Task.Supervisor
-    ],
-    Protocols: [
-      Collectable,
-      Enumerable,
-      Inspect,
-      Inspect.Algebra,
-      Inspect.Opts,
-      List.Chars,
-      Protocol,
-      String.Chars
-    ],
-    "Code & Macros": [
-      Code,
-      Code.Fragment,
-      Kernel.ParallelCompiler,
-      Macro,
-      Macro.Env
-    ]
-
-    ## Automatically detected groups
-
-    # Deprecated: [
-    #   Behaviour,
-    #   Dict,
-    #   GenEvent,
-    #   HashDict,
-    #   HashSet,
-    #   Set,
-    #   Supervisor.Spec
-    # ]
-  ]
-]

lib/elixir/generate_app.escript

@@ -1,13 +0,0 @@
-#!/usr/bin/env escript
-%% -*- erlang -*-
-
-main([Source, Target, Version]) ->
-  {ok, [{application, Name, Props0}]} = file:consult(Source),
-  Ebin = filename:dirname(Target),
-  Files = filelib:wildcard(filename:join(Ebin, "*.beam")),
-  Mods = [list_to_atom(filename:basename(F, ".beam")) || F <- Files],
-  Props1 = lists:keyreplace(modules, 1, Props0, {modules, Mods}),
-  Props = lists:keyreplace(vsn, 1, Props1, {vsn, Version}),
-  AppDef = io_lib:format("~tp.~n", [{application, Name, Props}]),
-  ok = file:write_file(Target, AppDef),
-  io:format("Generated ~ts app~n", [Name]).

lib/elixir/lib/access.ex

@@ -1,19 +1,27 @@
 defmodule Access do
   @moduledoc """
-  Key-based access to data structures.
+  Key-based access to data structures using the `data[key]` syntax.
 
-  The `Access` module defines a behaviour for dynamically accessing
-  keys of any type in a data structure via the `data[key]` syntax.
+  Elixir provides two syntaxes for accessing values. `user[:name]`
+  is used by dynamic structures, like maps and keywords, while
+  `user.name` is used by structs. The main difference is that
+  `user[:name]` won't raise if the key `:name` is missing but
+  `user.name` will raise if there is no `:name` key.
 
-  `Access` supports keyword lists (`Keyword`) and maps (`Map`) out
-  of the box. Keywords supports only atoms keys, keys for maps can
-  be of any type. Both return `nil` if the key does not exist:
+  Besides the cases above, this module provides convenience
+  functions for accessing other structures, like `at/1` for
+  lists and `elem/1` for tuples. Those functions can be used
+  by the nested update functions in `Kernel`, such as
+  `Kernel.get_in/2`, `Kernel.put_in/3`, `Kernel.update_in/3`,
+  `Kernel.get_and_update_in/3` and friends.
+
+  ## Dynamic lookups
+
+  Out of the box, `Access` works with `Keyword` and `Map`:
 
       iex> keywords = [a: 1, b: 2]
       iex> keywords[:a]
       1
-      iex> keywords[:c]
-      nil
 
       iex> map = %{a: 1, b: 2}
       iex> map[:a]
@@ -23,98 +31,120 @@ defmodule Access do
       iex> star_ratings[1.5]
       "★☆"
 
+  Note that the dynamic lookup syntax (`term[key]`) roughly translates to
+  `Access.get(term, key, nil)`.
+
+  `Access` can be combined with `Kernel.put_in/3` to put a value
+  in a given key:
+
+      iex> map = %{a: 1, b: 2}
+      iex> put_in map[:a], 3
+      %{a: 3, b: 2}
+
   This syntax is very convenient as it can be nested arbitrarily:
 
+      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
+      iex> put_in users["john"][:age], 28
+      %{"john" => %{age: 28}, "meg" => %{age: 23}}
+
+  Furthermore, `Access` transparently ignores `nil` values:
+
       iex> keywords = [a: 1, b: 2]
       iex> keywords[:c][:unknown]
       nil
 
-  This works because accessing anything on a `nil` value, returns
-  `nil` itself:
+  Since `Access` is a behaviour, it can be implemented for key-value
+  data structures. The implementation should be added to the
+  module that defines the struct being accessed. `Access` requires the
+  key comparison to be implemented using the `===` operator.
 
-      iex> nil[:a]
-      nil
+  ## Static lookups
 
-  The access syntax can also be used with the `Kernel.put_in/2`,
-  `Kernel.update_in/2` and `Kernel.get_and_update_in/2` macros
-  to allow values to be set in nested data structures:
+  The `Access` syntax (`foo[bar]`) cannot be used to access fields in
+  structs, since structs do not implement the `Access` behaviour by
+  default. It is also a design decision: the dynamic access lookup
+  is meant to be used for dynamic key-value structures, like maps
+  and keywords, and not by static ones like structs (where fields are
+  known and not dynamic).
 
-      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
-      iex> put_in(users["john"][:age], 28)
-      %{"john" => %{age: 28}, "meg" => %{age: 23}}
+  Therefore Elixir provides a static lookup for struct fields and for atom
+  fields in maps. Imagine a struct named `User` with a `:name` field.
+  The following would raise:
 
-  > Attention! While the access syntax is allowed in maps via
-  > `map[key]`, if your map is made of predefined atom keys,
-  > you should prefer to access those atom keys with `map.key`
-  > instead of `map[key]`, as `map.key` will raise if the key
-  > is missing (which is not supposed to happen if the keys are
-  > predefined). Similarly, since structs are maps and structs
-  > have predefined keys, they only allow the `struct.key`
-  > syntax and they do not allow the `struct[key]` access syntax.
-  > See the `Map` module for more information.
+      user = %User{name: "John"}
+      user[:name]
+      # ** (UndefinedFunctionError) undefined function User.fetch/2
+      #    (User does not implement the Access behaviour)
 
-  ## Nested data structures
+  Structs instead use the `user.name` syntax to access fields:
 
-  Both key-based access syntaxes can be used with the nested update
-  functions and macros in `Kernel`, such as `Kernel.get_in/2`,
-  `Kernel.put_in/3`, `Kernel.update_in/3`, `Kernel.pop_in/2`, and
-  `Kernel.get_and_update_in/3`.
+      user.name
+      #=> "John"
 
-  For example, to update a map inside another map:
+  The same `user.name` syntax can also be used by `Kernel.put_in/2`
+  to for updating structs fields:
 
-      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
-      iex> put_in(users["john"].age, 28)
-      %{"john" => %{age: 28}, "meg" => %{age: 23}}
+      put_in user.name, "Mary"
+      #=> %User{name: "Mary"}
 
-  This module provides convenience functions for traversing other
-  structures, like tuples and lists. These functions can be used
-  in all the `Access`-related functions and macros in `Kernel`.
+  Differently from `user[:name]`, `user.name` is not extensible via
+  a behaviour and is restricted only to structs and atom keys in maps.
 
-  For instance, given a user map with the `:name` and `:languages`
-  keys, here is how to deeply traverse the map and convert all
-  language names to uppercase:
+  As mentioned above, this works for atom keys in maps as well. Refer to the
+  `Map` module for more information on this.
 
-      iex> languages = [
-      ...>   %{name: "elixir", type: :functional},
-      ...>   %{name: "c", type: :procedural}
-      ...> ]
-      iex> user = %{name: "john", languages: languages}
-      iex> update_in(user, [:languages, Access.all(), :name], &String.upcase/1)
-      %{
-        name: "john",
-        languages: [
-          %{name: "ELIXIR", type: :functional},
-          %{name: "C", type: :procedural}
-        ]
-      }
+  Summing up:
+
+    * `user[:name]` is used by dynamic structures, is extensible and
+      does not raise on missing keys
+    * `user.name` is used by static structures, it is not extensible
+      and it will raise on missing keys
+
+  ## Accessors
+
+  While Elixir provides built-in syntax only for traversing dynamic
+  and static key-value structures, this module provides convenience
+  functions for traversing other structures, like tuples and lists,
+  to be used alongside `Kernel.put_in/2` in others.
+
+  For instance, given a user with a list of languages, here is how to
+  deeply traverse the map and convert all language names to uppercase:
+
+      iex> user = %{name: "john",
+      ...>          languages: [%{name: "elixir", type: :functional},
+      ...>                      %{name: "c", type: :procedural}]}
+      iex> update_in user, [:languages, Access.all(), :name], &String.upcase/1
+      %{name: "john",
+        languages: [%{name: "ELIXIR", type: :functional},
+                    %{name: "C", type: :procedural}]}
+
+  See the functions `key/1`, `key!/1`, `elem/1`, and `all/0` for some of the
+  available accessors.
+
+  ## Implementing the Access behaviour for custom data structures
+
+  In order to be able to use the `Access` protocol with custom data structures
+  (which have to be structs), such structures have to implement the `Access`
+  behaviour. For example, for a `User` struct, this would have to be done:
+
+      defmodule User do
+        defstruct [:name, :email]
+
+        @behaviour Access
+        # Implementation of the Access callbacks...
+      end
 
-  See the functions `key/1`, `key!/1`, `elem/1`, and `all/0` for
-  some of the available accessors.
   """
 
-  @type container :: keyword | struct | map
-  @type nil_container :: nil
-  @type any_container :: any
-  @type t :: container | nil_container | any_container
+  @type t :: list | map | nil | any
   @type key :: any
   @type value :: any
 
-  @type get_fun(data) ::
-          (:get, data, (term -> term) -> new_data :: container)
-
-  @type get_and_update_fun(data, current_value) ::
-          (:get_and_update, data, (term -> term) ->
-             {current_value, new_data :: container} | :pop)
-
-  @type access_fun(data, current_value) ::
-          get_fun(data) | get_and_update_fun(data, current_value)
-
   @doc """
   Invoked in order to access the value stored under `key` in the given term `term`.
 
   This function should return `{:ok, value}` where `value` is the value under
-  `key` if the key exists in the term, or `:error` if the key does not exist in
-  the term.
+  `key` if it succeeded, or `:error` if the key does not exist in the structure.
 
   Many of the functions defined in the `Access` module internally call this
   function. This function is also used when the square-brackets access syntax
@@ -123,234 +153,148 @@ defmodule Access do
   value}` then `value` is returned, or if it returns `:error` then `nil` is
   returned.
 
+
   See the `Map.fetch/2` and `Keyword.fetch/2` implementations for examples of
   how to implement this callback.
   """
   @callback fetch(term :: t, key) :: {:ok, value} | :error
 
+  @doc """
+  Invoked in order to access the value stored under `key` in the given term `term`,
+  defaulting to `default` if not present.
+
+  This function should return the value under the key `key` in `term` if there's
+  such key, otherwise `default`.
+
+  For most data structures, this can be implemented using `fetch/2` internally;
+  for example:
+
+      def get(structure, key, default) do
+        case fetch(structure, key) do
+          {:ok, value} -> value
+          :error       -> default
+        end
+      end
+
+  See the `Map.get/3` and `Keyword.get/3` implementations for more examples.
+  """
+  @callback get(term :: t, key, default :: value) :: value
+
   @doc """
   Invoked in order to access the value under `key` and update it at the same time.
 
-  The implementation of this callback should invoke `fun` with the value under
-  `key` in the passed structure `data`, or with `nil` if `key` is not present in it.
-  This function must return either `{current_value, new_value}` or `:pop`.
+  The implementation of this callback should invoke the passed function with the
+  value under key `key` in the passed structure, or `nil` if the key is not
+  present. This function should return either `{value_to_return, new_value}` or
+  `:pop`.
 
-  If the passed function returns `{current_value, new_value}`,
-  the return value of this callback should be `{current_value, new_data}`, where:
+  If it returns `{value_to_return, new_value}`, the return value of this
+  callback should be `{value_to_return, new_term}` where `new_term` is `term`
+  after updating the value of `key` with `new_value`.
 
-    * `current_value` is the retrieved value (which can be operated on before being returned)
-
-    * `new_value` is the new value to be stored under `key`
-
-    * `new_data` is `data` after updating the value of `key` with `new_value`.
-
-  If the passed function returns `:pop`, the return value of this callback
-  must be `{value, new_data}` where `value` is the value under `key`
-  (or `nil` if not present) and `new_data` is `data` without `key`.
+  If it returns `:pop`, the return value of this callback should be `{value,
+  new_term}` where `value` is the value under `key` or `nil` if not present, and
+  `new_term` is `term` without the key `key`.
 
   See the implementations of `Map.get_and_update/3` or `Keyword.get_and_update/3`
   for more examples.
   """
-  @callback get_and_update(data, key, (value | nil -> {current_value, new_value :: value} | :pop)) ::
-              {current_value, new_data :: data}
-            when current_value: value, data: container | any_container
+  @callback get_and_update(term :: t, key, (value -> {value, value} | :pop)) :: {value, t}
 
   @doc """
-  Invoked to "pop" the value under `key` out of the given data structure.
+  Invoked to "pop" the value under `key` out of the given term.
 
-  When `key` exists in the given structure `data`, the implementation should
-  return a `{value, new_data}` tuple where `value` is the value that was under
-  `key` and `new_data` is `term` without `key`.
+  When the key `key` exists in the given `term`, the implementation should
+  return a `{value, new_term}` tuple where `value` is the value that was under
+  `key` and `new_term` is `term` without `key`.
 
-  When `key` is not present in the given structure, a tuple `{value, data}`
+  When the key `key` is not present in the given `term`, a tuple `{value, term}`
   should be returned, where `value` is implementation-defined.
 
   See the implementations for `Map.pop/3` or `Keyword.pop/3` for more examples.
   """
-  @callback pop(data, key) :: {value, data} when data: container | any_container
+  @callback pop(term :: t, key) :: {value, t}
 
-  defmacrop raise_undefined_behaviour(exception, module, top) do
+  defmacrop raise_undefined_behaviour(e, struct, top) do
     quote do
-      exception =
-        case __STACKTRACE__ do
+      stacktrace = System.stacktrace
+      e =
+        case stacktrace do
           [unquote(top) | _] ->
-            reason = "#{inspect(unquote(module))} does not implement the Access behaviour"
-            %{unquote(exception) | reason: reason}
-
+            %{unquote(e) | reason: "#{inspect unquote(struct)} does not implement the Access behaviour"}
           _ ->
-            unquote(exception)
+            unquote(e)
         end
-
-      reraise exception, __STACKTRACE__
+      reraise e, stacktrace
     end
   end
 
   @doc """
   Fetches the value for the given key in a container (a map, keyword
   list, or struct that implements the `Access` behaviour).
-
-  Returns `{:ok, value}` where `value` is the value under `key` if there is such
-  a key, or `:error` if `key` is not found.
-
-  ## Examples
-
-      iex> Access.fetch(%{name: "meg", age: 26}, :name)
-      {:ok, "meg"}
-
-      iex> Access.fetch([ordered: true, on_timeout: :exit], :timeout)
-      :error
-
   """
-  @spec fetch(container, term) :: {:ok, term} | :error
-  @spec fetch(nil_container, any) :: :error
+  @spec fetch(t, term) :: {:ok, term} | :error
   def fetch(container, key)
 
-  def fetch(%module{} = container, key) do
-    module.fetch(container, key)
+  def fetch(%{__struct__: struct} = container, key) do
+    struct.fetch(container, key)
   rescue
-    exception in UndefinedFunctionError ->
-      raise_undefined_behaviour(exception, module, {^module, :fetch, [^container, ^key], _})
+    e in UndefinedFunctionError ->
+      raise_undefined_behaviour e, struct, {^struct, :fetch, [^container, ^key], _}
   end
 
   def fetch(map, key) when is_map(map) do
-    case map do
-      %{^key => value} -> {:ok, value}
-      _ -> :error
-    end
+    Map.fetch(map, key)
   end
 
   def fetch(list, key) when is_list(list) and is_atom(key) do
-    case :lists.keyfind(key, 1, list) do
-      {_, value} -> {:ok, value}
-      false -> :error
-    end
+    Keyword.fetch(list, key)
   end
 
   def fetch(list, key) when is_list(list) do
     raise ArgumentError,
-          "the Access calls for keywords expect the key to be an atom, got: " <> inspect(key)
+      "the Access calls for keywords expect the key to be an atom, got: " <> inspect(key)
   end
 
   def fetch(nil, _key) do
     :error
   end
 
-  @doc """
-  Same as `fetch/2` but returns the value directly,
-  or raises a `KeyError` exception if `key` is not found.
-
-  ## Examples
-
-      iex> Access.fetch!(%{name: "meg", age: 26}, :name)
-      "meg"
-
-  """
-  @doc since: "1.10.0"
-  @spec fetch!(container, term) :: term
-  def fetch!(container, key) do
-    case fetch(container, key) do
-      {:ok, value} -> value
-      :error -> raise(KeyError, key: key, term: container)
-    end
-  end
-
   @doc """
   Gets the value for the given key in a container (a map, keyword
   list, or struct that implements the `Access` behaviour).
-
-  Returns the value under `key` if there is such a key, or `default` if `key` is
-  not found.
-
-  ## Examples
-
-      iex> Access.get(%{name: "john"}, :name, "default name")
-      "john"
-      iex> Access.get(%{name: "john"}, :age, 25)
-      25
-
-      iex> Access.get([ordered: true], :timeout)
-      nil
-
   """
-  @spec get(container, term, term) :: term
-  @spec get(nil_container, any, default) :: default when default: var
-  def get(container, key, default \\ nil)
-
-  # Reimplementing the same logic as Access.fetch/2 here is done for performance, since
-  # this is called a lot and calling fetch/2 means introducing some overhead (like
-  # building the "{:ok, _}" tuple and deconstructing it back right away).
-
-  def get(%module{} = container, key, default) do
-    try do
-      module.fetch(container, key)
-    rescue
-      exception in UndefinedFunctionError ->
-        raise_undefined_behaviour(exception, module, {^module, :fetch, [^container, ^key], _})
-    else
+  @spec get(t, term, term) :: term
+  def get(container, key, default \\ nil) do
+    case fetch(container, key) do
       {:ok, value} -> value
       :error -> default
     end
   end
 
-  def get(map, key, default) when is_map(map) do
-    case map do
-      %{^key => value} -> value
-      _ -> default
-    end
-  end
-
-  def get(list, key, default) when is_list(list) and is_atom(key) do
-    case :lists.keyfind(key, 1, list) do
-      {_, value} -> value
-      false -> default
-    end
-  end
-
-  def get(list, key, _default) when is_list(list) do
-    raise ArgumentError,
-          "the Access calls for keywords expect the key to be an atom, got: " <> inspect(key)
-  end
-
-  def get(nil, _key, default) do
-    default
-  end
-
   @doc """
-  Gets and updates the given key in a `container` (a map, a keyword list,
-  a struct that implements the `Access` behaviour).
+  Gets and updates the given key in a container (a map, keyword
+  list, or struct that implements the `Access` behaviour).
 
-  The `fun` argument receives the value of `key` (or `nil` if `key` is not
-  present in `container`) and must return a two-element tuple `{current_value, new_value}`:
-  the "get" value `current_value` (the retrieved value, which can be operated on before
-  being returned) and the new value to be stored under `key` (`new_value`).
-  `fun` may also return `:pop`, which means the current value
-  should be removed from the container and returned.
+  This `fun` argument receives the value of `key` (or `nil` if `key`
+  is not present) and must return a two-element tuple: the "get" value
+  (the retrieved value, which can be operated on before being returned)
+  and the new value to be stored under `key`. The `fun` may also
+  return `:pop`, implying the current value shall be removed
+  from the container and returned.
 
   The returned value is a two-element tuple with the "get" value returned by
   `fun` and a new container with the updated value under `key`.
-
-  ## Examples
-
-      iex> Access.get_and_update([a: 1], :a, fn current_value ->
-      ...>   {current_value, current_value + 1}
-      ...> end)
-      {1, [a: 2]}
-
   """
-  @spec get_and_update(data, key, (value | nil -> {current_value, new_value :: value} | :pop)) ::
-          {current_value, new_data :: data}
-        when current_value: var, data: container
+  @spec get_and_update(container :: t, key, (value -> {get_value, update_value} | :pop)) ::
+        {get_value, container :: t} when get_value: var, update_value: value
   def get_and_update(container, key, fun)
 
-  def get_and_update(%module{} = container, key, fun) do
-    module.get_and_update(container, key, fun)
+  def get_and_update(%{__struct__: struct} = container, key, fun) do
+    struct.get_and_update(container, key, fun)
   rescue
-    exception in UndefinedFunctionError ->
-      raise_undefined_behaviour(
-        exception,
-        module,
-        {^module, :get_and_update, [^container, ^key, ^fun], _}
-      )
+    e in UndefinedFunctionError ->
+      raise_undefined_behaviour e, struct, {^struct, :get_and_update, [^container, ^key, ^fun], _}
   end
 
   def get_and_update(map, key, fun) when is_map(map) do
@@ -362,7 +306,8 @@ defmodule Access do
   end
 
   def get_and_update(nil, key, _fun) do
-    raise ArgumentError, "could not put/update key #{inspect(key)} on a nil value"
+    raise ArgumentError,
+      "could not put/update key #{inspect key} on a nil value"
   end
 
   @doc """
@@ -391,12 +336,11 @@ defmodule Access do
       {nil, %{creator: "Valim", name: "Elixir"}}
 
   """
-  @spec pop(data, key) :: {value, data} when data: container
-  def pop(%module{} = container, key) do
-    module.pop(container, key)
+  def pop(%{__struct__: struct} = container, key) do
+    struct.pop(container, key)
   rescue
-    exception in UndefinedFunctionError ->
-      raise_undefined_behaviour(exception, module, {^module, :pop, [^container, ^key], _})
+    e in UndefinedFunctionError ->
+      raise_undefined_behaviour e, struct, {^struct, :pop, [^container, ^key], _}
   end
 
   def pop(map, key) when is_map(map) do
@@ -408,11 +352,34 @@ defmodule Access do
   end
 
   def pop(nil, key) do
-    raise ArgumentError, "could not pop key #{inspect(key)} on a nil value"
+    raise ArgumentError,
+      "could not pop key #{inspect key} on a nil value"
   end
 
   ## Accessors
 
+  @doc false
+  def key(key) do
+    IO.warn "Access.key/1 is deprecated due to erratic behaviour for missing keys, " <>
+            "please use Access.key/2 instead with proper default values " <>
+            "(or Access.key!/1 if you expect the key to always be available)"
+
+    fn
+      :get, data, next ->
+        next.(Map.get(to_map(data), key))
+      :get_and_update, data, next ->
+        value = Map.get(to_map(data), key)
+        case next.(value) do
+          {get, update} -> {get, Map.put(data, key, update)}
+          :pop -> {value, Map.delete(data, key)}
+        end
+    end
+  end
+
+  defp to_map(nil), do: %{}
+  defp to_map(%{} = map), do: map
+  defp to_map(data), do: raise "Access.key/1 expected a map/struct or nil, got: #{inspect data}"
+
   @doc """
   Returns a function that accesses the given key in a map/struct.
 
@@ -422,13 +389,13 @@ defmodule Access do
   The returned function uses the default value if the key does not exist.
   This can be used to specify defaults and safely traverse missing keys:
 
-      iex> get_in(%{}, [Access.key(:user, %{}), Access.key(:name, "meg")])
-      "meg"
+      iex> get_in(%{}, [Access.key(:user, %{}), Access.key(:name, nil)])
+      nil
 
   Such is also useful when using update functions, allowing us to introduce
-  values as we traverse the data structure for updates:
+  values as we traverse the data-structure for updates:
 
-      iex> put_in(%{}, [Access.key(:user, %{}), Access.key(:name)], "Mary")
+      iex> put_in(%{}, [Access.key(:user, %{}), Access.key(:name, nil)], "Mary")
       %{user: %{name: "Mary"}}
 
   ## Examples
@@ -436,28 +403,28 @@ defmodule Access do
       iex> map = %{user: %{name: "john"}}
       iex> get_in(map, [Access.key(:unknown, %{}), Access.key(:name, "john")])
       "john"
-      iex> get_and_update_in(map, [Access.key(:user), Access.key(:name)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {"john", %{user: %{name: "JOHN"}}}
-      iex> pop_in(map, [Access.key(:user), Access.key(:name)])
+      iex> pop_in(map, [Access.key!(:user), Access.key!(:name)])
       {"john", %{user: %{}}}
 
   An error is raised if the accessed structure is not a map or a struct:
 
-      iex> get_in([], [Access.key(:foo)])
+      iex> get_in(nil, [Access.key(:foo, nil)])
+      ** (BadMapError) expected a map, got: nil
+
+      iex> get_in([], [Access.key(:foo, nil)])
       ** (BadMapError) expected a map, got: []
 
   """
-  @spec key(key, term) :: access_fun(data :: struct | map, current_value :: term)
-  def key(key, default \\ nil) do
+  def key(key, default) do
     fn
       :get, data, next ->
         next.(Map.get(data, key, default))
-
       :get_and_update, data, next ->
         value = Map.get(data, key, default)
-
         case next.(value) do
           {get, update} -> {get, Map.put(data, key, update)}
           :pop -> {value, Map.delete(data, key)}
@@ -471,15 +438,15 @@ defmodule Access do
   The returned function is typically passed as an accessor to `Kernel.get_in/2`,
   `Kernel.get_and_update_in/3`, and friends.
 
-  Similar to `key/2`, but the returned function raises if the key does not exist.
+  Raises if the key does not exist.
 
   ## Examples
 
       iex> map = %{user: %{name: "john"}}
       iex> get_in(map, [Access.key!(:user), Access.key!(:name)])
       "john"
-      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {"john", %{user: %{name: "JOHN"}}}
       iex> pop_in(map, [Access.key!(:user), Access.key!(:name)])
@@ -493,22 +460,18 @@ defmodule Access do
       ** (RuntimeError) Access.key!/1 expected a map/struct, got: []
 
   """
-  @spec key!(key) :: access_fun(data :: struct | map, current_value :: term)
   def key!(key) do
     fn
       :get, %{} = data, next ->
         next.(Map.fetch!(data, key))
-
       :get_and_update, %{} = data, next ->
         value = Map.fetch!(data, key)
-
         case next.(value) do
           {get, update} -> {get, Map.put(data, key, update)}
           :pop -> {value, Map.delete(data, key)}
         end
-
       _op, data, _next ->
-        raise "Access.key!/1 expected a map/struct, got: #{inspect(data)}"
+        raise "Access.key!/1 expected a map/struct, got: #{inspect data}"
     end
   end
 
@@ -518,18 +481,15 @@ defmodule Access do
   The returned function is typically passed as an accessor to `Kernel.get_in/2`,
   `Kernel.get_and_update_in/3`, and friends.
 
-  The returned function raises if `index` is out of bounds.
-
-  Note that popping elements out of tuples is not possible and raises an
-  error.
+  Raises if the index is out of bounds.
 
   ## Examples
 
       iex> map = %{user: {"john", 27}}
       iex> get_in(map, [:user, Access.elem(0)])
       "john"
-      iex> get_and_update_in(map, [:user, Access.elem(0)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(map, [:user, Access.elem(0)], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {"john", %{user: {"JOHN", 27}}}
       iex> pop_in(map, [:user, Access.elem(0)])
@@ -541,24 +501,20 @@ defmodule Access do
       ** (RuntimeError) Access.elem/1 expected a tuple, got: %{}
 
   """
-  @spec elem(non_neg_integer) :: access_fun(data :: tuple, current_value :: term)
-  def elem(index) when is_integer(index) and index >= 0 do
+  def elem(index) when is_integer(index) do
     pos = index + 1
 
     fn
       :get, data, next when is_tuple(data) ->
         next.(:erlang.element(pos, data))
-
       :get_and_update, data, next when is_tuple(data) ->
         value = :erlang.element(pos, data)
-
         case next.(value) do
           {get, update} -> {get, :erlang.setelement(pos, data, update)}
           :pop -> raise "cannot pop data from a tuple"
         end
-
       _op, data, _next ->
-        raise "Access.elem/1 expected a tuple, got: #{inspect(data)}"
+        raise "Access.elem/1 expected a tuple, got: #{inspect data}"
     end
   end
 
@@ -573,19 +529,19 @@ defmodule Access do
       iex> list = [%{name: "john"}, %{name: "mary"}]
       iex> get_in(list, [Access.all(), :name])
       ["john", "mary"]
-      iex> get_and_update_in(list, [Access.all(), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(list, [Access.all(), :name], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {["john", "mary"], [%{name: "JOHN"}, %{name: "MARY"}]}
       iex> pop_in(list, [Access.all(), :name])
       {["john", "mary"], [%{}, %{}]}
 
   Here is an example that traverses the list dropping even
-  numbers and multiplying odd numbers by 2:
+  numbers and multipling odd numbers by 2:
 
       iex> require Integer
-      iex> get_and_update_in([1, 2, 3, 4, 5], [Access.all()], fn num ->
-      ...>   if Integer.is_even(num), do: :pop, else: {num, num * 2}
+      iex> get_and_update_in([1, 2, 3, 4, 5], [Access.all], fn
+      ...>   num -> if Integer.is_even(num), do: :pop, else: {num, num * 2}
       ...> end)
       {[1, 2, 3, 4, 5], [2, 6, 10]}
 
@@ -595,7 +551,6 @@ defmodule Access do
       ** (RuntimeError) Access.all/0 expected a list, got: %{}
 
   """
-  @spec all() :: access_fun(data :: list, current_value :: list)
   def all() do
     &all/3
   end
@@ -605,11 +560,11 @@ defmodule Access do
   end
 
   defp all(:get_and_update, data, next) when is_list(data) do
-    all(data, next, _gets = [], _updates = [])
+    all(data, next, [], [])
   end
 
   defp all(_op, data, _next) do
-    raise "Access.all/0 expected a list, got: #{inspect(data)}"
+    raise "Access.all/0 expected a list, got: #{inspect data}"
   end
 
   defp all([head | rest], next, gets, updates) do
@@ -634,16 +589,10 @@ defmodule Access do
       iex> list = [%{name: "john"}, %{name: "mary"}]
       iex> get_in(list, [Access.at(1), :name])
       "mary"
-      iex> get_in(list, [Access.at(-1), :name])
-      "mary"
-      iex> get_and_update_in(list, [Access.at(0), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(list, [Access.at(0), :name], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {"john", [%{name: "JOHN"}, %{name: "mary"}]}
-      iex> get_and_update_in(list, [Access.at(-1), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {"mary", [%{name: "john"}, %{name: "MARY"}]}
 
   `at/1` can also be used to pop elements out of a list or
   a key inside of a list:
@@ -659,20 +608,23 @@ defmodule Access do
       iex> list = [%{name: "john"}, %{name: "mary"}]
       iex> get_in(list, [Access.at(10), :name])
       nil
-      iex> get_and_update_in(list, [Access.at(10), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
+      iex> get_and_update_in(list, [Access.at(10), :name], fn
+      ...>   prev -> {prev, String.upcase(prev)}
       ...> end)
       {nil, [%{name: "john"}, %{name: "mary"}]}
 
+  An error is raised for negative indexes:
+
+      iex> get_in([], [Access.at(-1)])
+      ** (FunctionClauseError) no function clause matching in Access.at/1
+
   An error is raised if the accessed structure is not a list:
 
       iex> get_in(%{}, [Access.at(1)])
       ** (RuntimeError) Access.at/1 expected a list, got: %{}
-
   """
-  @spec at(integer) :: access_fun(data :: list, current_value :: term)
-  def at(index) when is_integer(index) do
-    fn op, data, next -> at(op, data, index, next) end
+  def at(index) when index >= 0 do
+    fn(op, data, next) -> at(op, data, index, next) end
   end
 
   defp at(:get, data, index, next) when is_list(data) do
@@ -680,150 +632,25 @@ defmodule Access do
   end
 
   defp at(:get_and_update, data, index, next) when is_list(data) do
-    get_and_update_at(data, index, next, [], fn -> nil end)
+    get_and_update_at(data, index, next, [])
   end
 
   defp at(_op, data, _index, _next) do
-    raise "Access.at/1 expected a list, got: #{inspect(data)}"
+    raise "Access.at/1 expected a list, got: #{inspect data}"
   end
 
-  defp get_and_update_at([head | rest], 0, next, updates, _default_fun) do
+  defp get_and_update_at([head | rest], 0, next, updates) do
     case next.(head) do
       {get, update} -> {get, :lists.reverse([update | updates], rest)}
       :pop -> {head, :lists.reverse(updates, rest)}
     end
   end
 
-  defp get_and_update_at([_ | _] = list, index, next, updates, default_fun) when index < 0 do
-    list_length = length(list)
-
-    if list_length + index >= 0 do
-      get_and_update_at(list, list_length + index, next, updates, default_fun)
-    else
-      {default_fun.(), list}
-    end
+  defp get_and_update_at([head | rest], index, next, updates) do
+    get_and_update_at(rest, index - 1, next, [head | updates])
   end
 
-  defp get_and_update_at([head | rest], index, next, updates, default_fun) when index > 0 do
-    get_and_update_at(rest, index - 1, next, [head | updates], default_fun)
-  end
-
-  defp get_and_update_at([], _index, _next, updates, default_fun) do
-    {default_fun.(), :lists.reverse(updates)}
-  end
-
-  @doc ~S"""
-  Same as `at/1` except that it raises `Enum.OutOfBoundsError`
-  if the given index is out of bounds.
-
-  ## Examples
-
-      iex> get_in([:a, :b, :c], [Access.at!(2)])
-      :c
-      iex> get_in([:a, :b, :c], [Access.at!(3)])
-      ** (Enum.OutOfBoundsError) out of bounds error
-
-  """
-  @doc since: "1.11.0"
-  @spec at!(integer) :: access_fun(data :: list, current_value :: term)
-  def at!(index) when is_integer(index) do
-    fn op, data, next -> at!(op, data, index, next) end
-  end
-
-  defp at!(:get, data, index, next) when is_list(data) do
-    case Enum.fetch(data, index) do
-      {:ok, value} -> next.(value)
-      :error -> raise Enum.OutOfBoundsError
-    end
-  end
-
-  defp at!(:get_and_update, data, index, next) when is_list(data) do
-    get_and_update_at(data, index, next, [], fn -> raise Enum.OutOfBoundsError end)
-  end
-
-  defp at!(_op, data, _index, _next) do
-    raise "Access.at!/1 expected a list, got: #{inspect(data)}"
-  end
-
-  @doc ~S"""
-  Returns a function that accesses all elements of a list that match the provided predicate.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  ## Examples
-
-      iex> list = [%{name: "john", salary: 10}, %{name: "francine", salary: 30}]
-      iex> get_in(list, [Access.filter(&(&1.salary > 20)), :name])
-      ["francine"]
-      iex> get_and_update_in(list, [Access.filter(&(&1.salary <= 20)), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {["john"], [%{name: "JOHN", salary: 10}, %{name: "francine", salary: 30}]}
-
-  `filter/1` can also be used to pop elements out of a list or
-  a key inside of a list:
-
-      iex> list = [%{name: "john", salary: 10}, %{name: "francine", salary: 30}]
-      iex> pop_in(list, [Access.filter(&(&1.salary >= 20))])
-      {[%{name: "francine", salary: 30}], [%{name: "john", salary: 10}]}
-      iex> pop_in(list, [Access.filter(&(&1.salary >= 20)), :name])
-      {["francine"], [%{name: "john", salary: 10}, %{salary: 30}]}
-
-  When no match is found, an empty list is returned and the update function is never called
-
-      iex> list = [%{name: "john", salary: 10}, %{name: "francine", salary: 30}]
-      iex> get_in(list, [Access.filter(&(&1.salary >= 50)), :name])
-      []
-      iex> get_and_update_in(list, [Access.filter(&(&1.salary >= 50)), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {[], [%{name: "john", salary: 10}, %{name: "francine", salary: 30}]}
-
-  An error is raised if the predicate is not a function or is of the incorrect arity:
-
-      iex> get_in([], [Access.filter(5)])
-      ** (FunctionClauseError) no function clause matching in Access.filter/1
-
-  An error is raised if the accessed structure is not a list:
-
-      iex> get_in(%{}, [Access.filter(fn a -> a == 10 end)])
-      ** (RuntimeError) Access.filter/1 expected a list, got: %{}
-
-  """
-  @doc since: "1.6.0"
-  @spec filter((term -> boolean)) :: access_fun(data :: list, current_value :: list)
-  def filter(func) when is_function(func) do
-    fn op, data, next -> filter(op, data, func, next) end
-  end
-
-  defp filter(:get, data, func, next) when is_list(data) do
-    data |> Enum.filter(func) |> Enum.map(next)
-  end
-
-  defp filter(:get_and_update, data, func, next) when is_list(data) do
-    get_and_update_filter(data, func, next, [], [])
-  end
-
-  defp filter(_op, data, _func, _next) do
-    raise "Access.filter/1 expected a list, got: #{inspect(data)}"
-  end
-
-  defp get_and_update_filter([head | rest], func, next, updates, gets) do
-    if func.(head) do
-      case next.(head) do
-        {get, update} ->
-          get_and_update_filter(rest, func, next, [update | updates], [get | gets])
-
-        :pop ->
-          get_and_update_filter(rest, func, next, updates, [head | gets])
-      end
-    else
-      get_and_update_filter(rest, func, next, [head | updates], gets)
-    end
-  end
-
-  defp get_and_update_filter([], _func, _next, updates, gets) do
-    {:lists.reverse(gets), :lists.reverse(updates)}
+  defp get_and_update_at([], _index, _next, updates) do
+    {nil, :lists.reverse(updates)}
   end
 end

lib/elixir/lib/agent.ex

@@ -6,55 +6,48 @@ defmodule Agent do
   must be accessed from different processes or by the same process
   at different points in time.
 
-  The `Agent` module provides a basic server implementation that
+  The Agent module provides a basic server implementation that
   allows state to be retrieved and updated via a simple API.
 
   ## Examples
 
-  For example, the following agent implements a counter:
+  For example, in the Mix tool that ships with Elixir, we need
+  to keep a set of all tasks executed by a given project. Since
+  this set is shared, we can implement it with an Agent:
 
-      defmodule Counter do
-        use Agent
-
-        def start_link(initial_value) do
-          Agent.start_link(fn -> initial_value end, name: __MODULE__)
+      defmodule Mix.TasksServer do
+        def start_link do
+          Agent.start_link(fn -> MapSet.new end, name: __MODULE__)
         end
 
-        def value do
-          Agent.get(__MODULE__, & &1)
+        @doc "Checks if the task has already executed"
+        def executed?(task, project) do
+          item = {task, project}
+          Agent.get(__MODULE__, fn set ->
+            item in set
+          end)
         end
 
-        def increment do
-          Agent.update(__MODULE__, &(&1 + 1))
+        @doc "Marks a task as executed"
+        def put_task(task, project) do
+          item = {task, project}
+          Agent.update(__MODULE__, &MapSet.put(&1, item))
+        end
+
+        @doc "Resets the executed tasks and returns the previous list of tasks"
+        def take_all() do
+          Agent.get_and_update(__MODULE__, fn set ->
+            {Enum.into(set, []), MapSet.new}
+          end)
         end
       end
 
-  Usage would be:
-
-      Counter.start_link(0)
-      #=> {:ok, #PID<0.123.0>}
-
-      Counter.value()
-      #=> 0
-
-      Counter.increment()
-      #=> :ok
-
-      Counter.increment()
-      #=> :ok
-
-      Counter.value()
-      #=> 2
-
-  Thanks to the agent server process, the counter can be safely incremented
-  concurrently.
-
-  Agents provide a segregation between the client and server APIs (similar to
-  `GenServer`s). In particular, the functions passed as arguments to the calls to
-  `Agent` functions are invoked inside the agent (the server). This distinction
-  is important because you may want to avoid expensive operations inside the
-  agent, as they will effectively block the agent until the request is
-  fulfilled.
+  Note that agents still provide a segregation between the
+  client and server APIs, as seen in GenServers. In particular,
+  all code inside the function passed to the agent is executed
+  by the agent. This distinction is important because you may
+  want to avoid expensive operations inside the agent, as it will
+  effectively block the agent until the request is fulfilled.
 
   Consider these two examples:
 
@@ -65,79 +58,19 @@ defmodule Agent do
 
       # Compute in the agent/client
       def get_something(agent) do
-        Agent.get(agent, & &1) |> do_something_expensive()
+        Agent.get(agent, &(&1)) |> do_something_expensive()
       end
 
-  The first function blocks the agent. The second function copies all the state
-  to the client and then executes the operation in the client. One aspect to
-  consider is whether the data is large enough to require processing in the server,
-  at least initially, or small enough to be sent to the client cheaply. Another
-  factor is whether the data needs to be processed atomically: getting the
-  state and calling `do_something_expensive(state)` outside of the agent means
-  that the agent's state can be updated in the meantime. This is specially
-  important in case of updates as computing the new state in the client rather
-  than in the server can lead to race conditions if multiple clients are trying
-  to update the same state to different values.
+  The first function blocks the agent. The second function copies
+  all the state to the client and then executes the operation in the
+  client. The difference is whether the data is large enough to require
+  processing in the server, at least initially, or small enough to be
+  sent to the client cheaply.
 
-  ## How to supervise
+  ## Name Registration
 
-  An `Agent` is most commonly started under a supervision tree.
-  When we invoke `use Agent`, it automatically defines a `child_spec/1`
-  function that allows us to start the agent directly under a supervisor.
-  To start an agent under a supervisor with an initial counter of 0,
-  one may do:
-
-      children = [
-        {Counter, 0}
-      ]
-
-      Supervisor.start_link(children, strategy: :one_for_all)
-
-  While one could also simply pass the `Counter` as a child to the supervisor,
-  such as:
-
-      children = [
-        Counter # Same as {Counter, []}
-      ]
-
-      Supervisor.start_link(children, strategy: :one_for_all)
-
-  The definition above wouldn't work for this particular example,
-  as it would attempt to start the counter with an initial value
-  of an empty list. However, this may be a viable option in your
-  own agents. A common approach is to use a keyword list, as that
-  would allow setting the initial value and giving a name to the
-  counter process, for example:
-
-      def start_link(opts) do
-        {initial_value, opts} = Keyword.pop(opts, :initial_value, 0)
-        Agent.start_link(fn -> initial_value end, opts)
-      end
-
-  and then you can use `Counter`, `{Counter, name: :my_counter}` or
-  even `{Counter, initial_value: 0, name: :my_counter}` as a child
-  specification.
-
-  `use Agent` also accepts a list of options which configures the
-  child specification and therefore how it runs under a supervisor.
-  The generated `child_spec/1` can be customized with the following options:
-
-    * `:id` - the child specification identifier, defaults to the current module
-    * `:restart` - when the child should be restarted, defaults to `:permanent`
-    * `:shutdown` - how to shut down the child, either immediately or by giving it time to shut down
-
-  For example:
-
-      use Agent, restart: :transient, shutdown: 10_000
-
-  See the "Child specification" section in the `Supervisor` module for more
-  detailed information. The `@doc` annotation immediately preceding
-  `use Agent` will be attached to the generated `child_spec/1` function.
-
-  ## Name registration
-
-  An agent is bound to the same name registration rules as GenServers.
-  Read more about it in the `GenServer` documentation.
+  An Agent is bound to the same name registration rules as GenServers.
+  Read more about it in the `GenServer` docs.
 
   ## A word on distributed agents
 
@@ -162,15 +95,14 @@ defmodule Agent do
   ## Hot code swapping
 
   An agent can have its code hot swapped live by simply passing a module,
-  function, and arguments tuple to the update instruction. For example, imagine
+  function, and args tuple to the update instruction. For example, imagine
   you have an agent named `:sample` and you want to convert its inner state
-  from a keyword list to a map. It can be done with the following
+  from some dict structure to a map. It can be done with the following
   instruction:
 
       {:update, :sample, {:advanced, {Enum, :into, [%{}]}}}
 
-  The agent's state will be added to the given list of arguments (`[%{}]`) as
-  the first argument.
+  The agent's state will be added to the given list as the first argument.
   """
 
   @typedoc "Return values of `start*` functions"
@@ -185,51 +117,14 @@ defmodule Agent do
   @typedoc "The agent state"
   @type state :: term
 
-  @doc """
-  Returns a specification to start an agent under a supervisor.
-
-  See the "Child specification" section in the `Supervisor` module for more detailed information.
-  """
-  @doc since: "1.5.0"
-  def child_spec(arg) do
-    %{
-      id: Agent,
-      start: {Agent, :start_link, [arg]}
-    }
-  end
-
-  @doc false
-  defmacro __using__(opts) do
-    quote location: :keep, bind_quoted: [opts: opts] do
-      unless Module.has_attribute?(__MODULE__, :doc) do
-        @doc """
-        Returns a specification to start this module under a supervisor.
-
-        See `Supervisor`.
-        """
-      end
-
-      def child_spec(arg) do
-        default = %{
-          id: __MODULE__,
-          start: {__MODULE__, :start_link, [arg]}
-        }
-
-        Supervisor.child_spec(default, unquote(Macro.escape(opts)))
-      end
-
-      defoverridable child_spec: 1
-    end
-  end
-
   @doc """
   Starts an agent linked to the current process with the given function.
 
   This is often used to start the agent as part of a supervision tree.
 
-  Once the agent is spawned, the given function `fun` is invoked in the server
-  process, and should return the initial agent state. Note that `start_link/2`
-  does not return until the given function has returned.
+  Once the agent is spawned, the given function is invoked and its return
+  value is used as the agent state. Note that `start_link` does not return
+  until the given function has returned.
 
   ## Options
 
@@ -241,7 +136,7 @@ defmodule Agent do
   and the start function will return `{:error, :timeout}`.
 
   If the `:debug` option is present, the corresponding function in the
-  [`:sys` module](`:sys`) will be invoked.
+  [`:sys` module](http://www.erlang.org/doc/man/sys.html) will be invoked.
 
   If the `:spawn_opt` option is present, its value will be passed as options
   to the underlying process as in `Process.spawn/4`.
@@ -253,32 +148,22 @@ defmodule Agent do
   specified name already exists, the function returns
   `{:error, {:already_started, pid}}` with the PID of that process.
 
-  If the given function callback fails, the function returns `{:error, reason}`.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.get(pid, fn state -> state end)
-      42
-
-      iex> {:error, {exception, _stacktrace}} = Agent.start(fn -> raise "oops" end)
-      iex> exception
-      %RuntimeError{message: "oops"}
-
+  If the given function callback fails with `reason`, the function returns
+  `{:error, reason}`.
   """
-  @spec start_link((() -> term), GenServer.options()) :: on_start
+  @spec start_link((() -> term), GenServer.options) :: on_start
   def start_link(fun, options \\ []) when is_function(fun, 0) do
     GenServer.start_link(Agent.Server, fun, options)
   end
 
   @doc """
-  Starts an agent linked to the current process.
+  Starts an agent linked to the current process with the given module
+  function and arguments.
 
-  Same as `start_link/2` but a module, function, and arguments are expected
-  instead of an anonymous function; `fun` in `module` will be called with the
-  given arguments `args` to initialize the state.
+  Same as `start_link/2` but a module, function and args are expected
+  instead of an anonymous function.
   """
-  @spec start_link(module, atom, [any], GenServer.options()) :: on_start
+  @spec start_link(module, atom, [any], GenServer.options) :: on_start
   def start_link(module, fun, args, options \\ []) do
     GenServer.start_link(Agent.Server, {module, fun, args}, options)
   end
@@ -287,48 +172,31 @@ defmodule Agent do
   Starts an agent process without links (outside of a supervision tree).
 
   See `start_link/2` for more information.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start(fn -> 42 end)
-      iex> Agent.get(pid, fn state -> state end)
-      42
-
   """
-  @spec start((() -> term), GenServer.options()) :: on_start
+  @spec start((() -> term), GenServer.options) :: on_start
   def start(fun, options \\ []) when is_function(fun, 0) do
     GenServer.start(Agent.Server, fun, options)
   end
 
   @doc """
-  Starts an agent without links with the given module, function, and arguments.
+  Starts an agent with the given module function and arguments.
 
-  See `start_link/4` for more information.
+  Similar to `start/2` but a module, function and args are expected
+  instead of an anonymous function.
   """
-  @spec start(module, atom, [any], GenServer.options()) :: on_start
+  @spec start(module, atom, [any], GenServer.options) :: on_start
   def start(module, fun, args, options \\ []) do
     GenServer.start(Agent.Server, {module, fun, args}, options)
   end
 
   @doc """
-  Gets an agent value via the given anonymous function.
+  Gets an agent value via the given function.
 
   The function `fun` is sent to the `agent` which invokes the function
   passing the agent state. The result of the function invocation is
-  returned from this function.
-
-  `timeout` is an integer greater than zero which specifies how many
-  milliseconds are allowed before the agent executes the function and returns
-  the result value, or the atom `:infinity` to wait indefinitely. If no result
-  is received within the specified time, the function call fails and the caller
-  exits.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.get(pid, fn state -> state end)
-      42
+  returned.
 
+  A timeout can also be specified (it has a default value of 5000).
   """
   @spec get(agent, (state -> a), timeout) :: a when a: var
   def get(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
@@ -338,9 +206,9 @@ defmodule Agent do
   @doc """
   Gets an agent value via the given function.
 
-  Same as `get/3` but a module, function, and arguments are expected
+  Same as `get/3` but a module, function and args are expected
   instead of an anonymous function. The state is added as first
-  argument to the given list of arguments.
+  argument to the given list of args.
   """
   @spec get(agent, module, atom, [term], timeout) :: any
   def get(agent, module, fun, args, timeout \\ 5000) do
@@ -348,28 +216,14 @@ defmodule Agent do
   end
 
   @doc """
-  Gets and updates the agent state in one operation via the given anonymous
-  function.
+  Gets and updates the agent state in one operation.
 
   The function `fun` is sent to the `agent` which invokes the function
   passing the agent state. The function must return a tuple with two
-  elements, the first being the value to return (that is, the "get" value)
-  and the second one being the new state of the agent.
-
-  `timeout` is an integer greater than zero which specifies how many
-  milliseconds are allowed before the agent executes the function and returns
-  the result value, or the atom `:infinity` to wait indefinitely. If no result
-  is received within the specified time, the function call fails and the caller
-  exits.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.get_and_update(pid, fn state -> {state, state + 1} end)
-      42
-      iex> Agent.get(pid, fn state -> state end)
-      43
+  elements, the first being the value to return (i.e. the `get` value)
+  and the second one is the new state.
 
+  A timeout can also be specified (it has a default value of 5000).
   """
   @spec get_and_update(agent, (state -> {a, state}), timeout) :: a when a: var
   def get_and_update(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
@@ -377,11 +231,11 @@ defmodule Agent do
   end
 
   @doc """
-  Gets and updates the agent state in one operation via the given function.
+  Gets and updates the agent state in one operation.
 
-  Same as `get_and_update/3` but a module, function, and arguments are expected
+  Same as `get_and_update/3` but a module, function and args are expected
   instead of an anonymous function. The state is added as first
-  argument to the given list of arguments.
+  argument to the given list of args.
   """
   @spec get_and_update(agent, module, atom, [term], timeout) :: any
   def get_and_update(agent, module, fun, args, timeout \\ 5000) do
@@ -389,28 +243,13 @@ defmodule Agent do
   end
 
   @doc """
-  Updates the agent state via the given anonymous function.
+  Updates the agent state.
 
   The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The return value of `fun` becomes the new
-  state of the agent.
+  passing the agent state. The function must return the new state.
 
+  A timeout can also be specified (it has a default value of 5000).
   This function always returns `:ok`.
-
-  `timeout` is an integer greater than zero which specifies how many
-  milliseconds are allowed before the agent executes the function and returns
-  the result value, or the atom `:infinity` to wait indefinitely. If no result
-  is received within the specified time, the function call fails and the caller
-  exits.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.update(pid, fn state -> state + 1 end)
-      :ok
-      iex> Agent.get(pid, fn state -> state end)
-      43
-
   """
   @spec update(agent, (state -> state), timeout) :: :ok
   def update(agent, fun, timeout \\ 5000) when is_function(fun, 1) do
@@ -418,20 +257,11 @@ defmodule Agent do
   end
 
   @doc """
-  Updates the agent state via the given function.
+  Updates the agent state.
 
-  Same as `update/3` but a module, function, and arguments are expected
+  Same as `update/3` but a module, function and args are expected
   instead of an anonymous function. The state is added as first
-  argument to the given list of arguments.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.update(pid, Kernel, :+, [12])
-      :ok
-      iex> Agent.get(pid, fn state -> state end)
-      54
-
+  argument to the given list of args.
   """
   @spec update(agent, module, atom, [term], timeout) :: :ok
   def update(agent, module, fun, args, timeout \\ 5000) do
@@ -439,23 +269,13 @@ defmodule Agent do
   end
 
   @doc """
-  Performs a cast (*fire and forget*) operation on the agent state.
+  Performs a cast (fire and forget) operation on the agent state.
 
   The function `fun` is sent to the `agent` which invokes the function
-  passing the agent state. The return value of `fun` becomes the new
-  state of the agent.
-
-  Note that `cast` returns `:ok` immediately, regardless of whether `agent` (or
-  the node it should live on) exists.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.cast(pid, fn state -> state + 1 end)
-      :ok
-      iex> Agent.get(pid, fn state -> state end)
-      43
+  passing the agent state. The function must return the new state.
 
+  Note that `cast` returns `:ok` immediately, regardless of whether the
+  destination node or agent exists.
   """
   @spec cast(agent, (state -> state)) :: :ok
   def cast(agent, fun) when is_function(fun, 1) do
@@ -463,20 +283,11 @@ defmodule Agent do
   end
 
   @doc """
-  Performs a cast (*fire and forget*) operation on the agent state.
+  Performs a cast (fire and forget) operation on the agent state.
 
-  Same as `cast/2` but a module, function, and arguments are expected
+  Same as `cast/2` but a module, function and args are expected
   instead of an anonymous function. The state is added as first
-  argument to the given list of arguments.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.cast(pid, Kernel, :+, [12])
-      :ok
-      iex> Agent.get(pid, fn state -> state end)
-      54
-
+  argument to the given list of args.
   """
   @spec cast(agent, module, atom, [term]) :: :ok
   def cast(agent, module, fun, args) do
@@ -484,25 +295,18 @@ defmodule Agent do
   end
 
   @doc """
-  Synchronously stops the agent with the given `reason`.
+  Stops the agent with the given `reason`.
 
-  It returns `:ok` if the agent terminates with the given
-  reason. If the agent terminates with another reason, the call will
+  It returns `:ok` if the server terminates with the given
+  reason, if it terminates with another reason, the call will
   exit.
 
   This function keeps OTP semantics regarding error reporting.
   If the reason is any other than `:normal`, `:shutdown` or
   `{:shutdown, _}`, an error report will be logged.
-
-  ## Examples
-
-      iex> {:ok, pid} = Agent.start_link(fn -> 42 end)
-      iex> Agent.stop(pid)
-      :ok
-
   """
   @spec stop(agent, reason :: term, timeout) :: :ok
   def stop(agent, reason \\ :normal, timeout \\ :infinity) do
-    GenServer.stop(agent, reason, timeout)
+    :gen.stop(agent, reason, timeout)
   end
 end

lib/elixir/lib/agent/server.ex

@@ -15,7 +15,7 @@ defmodule Agent.Server do
   def handle_call({:get_and_update, fun}, _from, state) do
     case run(fun, [state]) do
       {reply, state} -> {:reply, reply, state}
-      other -> {:stop, {:bad_return_value, other}, state}
+      other          -> {:stop, {:bad_return_value, other}, state}
     end
   end
 
@@ -23,10 +23,18 @@ defmodule Agent.Server do
     {:reply, :ok, run(fun, [state])}
   end
 
+  def handle_call(msg, from, state) do
+    super(msg, from, state)
+  end
+
   def handle_cast({:cast, fun}, state) do
     {:noreply, run(fun, [state])}
   end
 
+  def handle_cast(msg, state) do
+    super(msg, state)
+  end
+
   def code_change(_old, state, fun) do
     {:ok, run(fun, [state])}
   end
@@ -37,8 +45,8 @@ defmodule Agent.Server do
   end
 
   defp get_initial_call(fun) when is_function(fun, 0) do
-    {:module, module} = Function.info(fun, :module)
-    {:name, name} = Function.info(fun, :name)
+    {:module, module} = :erlang.fun_info(fun, :module)
+    {:name, name} = :erlang.fun_info(fun, :name)
     {module, name, 0}
   end
 

lib/elixir/lib/application.ex

@@ -2,286 +2,98 @@ defmodule Application do
   @moduledoc """
   A module for working with applications and defining application callbacks.
 
-  Applications are the idiomatic way to package software in Erlang/OTP. To get
-  the idea, they are similar to the "library" concept common in other
-  programming languages, but with some additional characteristics.
+  In Elixir (actually, in Erlang/OTP), an application is a component
+  implementing some specific functionality, that can be started and stopped
+  as a unit, and which can be re-used in other systems.
 
-  An application is a component implementing some specific functionality, with a
-  standardized directory structure, configuration, and life cycle. Applications
-  are *loaded*, *started*, and *stopped*. Each application also has its own
-  environment, which provides a unified API for configuring each application.
+  Applications are defined with an application file named `APP.app` where
+  `APP` is the application name, usually in `underscore_case`. The application
+  file must reside in the same `ebin` directory as the compiled modules of the
+  application.
 
-  Developers typically interact with the application environment and its
-  callback module. Therefore those will be the topics we will cover first
-  before jumping into details about the application resource file and life-cycle.
+  In Elixir, Mix is responsible for compiling your source code and
+  generating your application `.app` file. Furthermore, Mix is also
+  responsible for configuring, starting and stopping your application
+  and its dependencies. For this reason, this documentation will focus
+  on the remaining aspects of your application: the application environment
+  and the application callback module.
 
-  ## The application environment
+  You can learn more about Mix generation of `.app` files by typing
+  `mix help compile.app`.
 
-  Each application has its own environment. The environment is a keyword list
-  that maps atoms to terms. Note that this environment is unrelated to the
-  operating system environment.
+  ## Application environment
 
-  By default, the environment of an application is an empty list. In a Mix
-  project's `mix.exs` file, you can set the `:env` key in `application/0`:
+  Once an application is started, OTP provides an application environment
+  that can be used to configure the application.
+
+  Assuming you are inside a Mix project, you can edit the `application/0`
+  function in the `mix.exs` file to the following:
 
       def application do
-        [env: [db_host: "localhost"]]
+        [env: [hello: :world]]
       end
 
-  Now, in your application, you can read this environment by using functions
-  such as `fetch_env!/2` and friends:
+  In the application function, we can define the default environment values
+  for our application. By starting your application with `iex -S mix`, you
+  can access the default value:
 
-      defmodule MyApp.DBClient do
-        def start_link() do
-          SomeLib.DBClient.start_link(host: db_host())
-        end
+      Application.get_env(:APP_NAME, :hello)
+      #=> :world
 
-        defp db_host do
-          Application.fetch_env!(:my_app, :db_host)
-        end
-      end
+  It is also possible to put and delete values from the application value,
+  including new values that are not defined in the environment file (although
+  this should be avoided).
 
-  In Mix projects, the environment of the application and its dependencies can
-  be overridden via the `config/config.exs` and `config/runtime.exs` files. The
-  former is loaded at build-time, before your code compiles, and the latter at
-  runtime, just before your app starts. For example, someone using your application
-  can override its `:db_host` environment variable as follows:
+  Keep in mind that each application is responsible for its environment.
+  Do not use the functions in this module for directly accessing or modifying
+  the environment of other applications (as it may lead to inconsistent
+  data in the application environment).
 
-      import Config
-      config :my_app, :db_host, "db.local"
+  ## Application module callback
 
-  See the "Configuration" section in the `Mix` module for more information.
-
-  You can also change the application environment dynamically by using functions
-  such as `put_env/3` and `delete_env/2`. However, as a rule of thumb, each application
-  is responsible for its own environment. Please do not use the functions in this
-  module for directly accessing or modifying the environment of other applications.
-
-  ### Compile-time environment
-
-  In the previous example, we read the application environment at runtime:
-
-      defmodule MyApp.DBClient do
-        def start_link() do
-          SomeLib.DBClient.start_link(host: db_host())
-        end
-
-        defp db_host do
-          Application.fetch_env!(:my_app, :db_host)
-        end
-      end
-
-  In other words, the environment key `:db_host` for application `:my_app`
-  will only be read when `MyApp.DBClient` effectively starts. While reading
-  the application environment at runtime is the preferred approach, in some
-  rare occasions you may want to use the application environment to configure
-  the compilation of a certain project. This is often done by calling `get_env/3`
-  outside of a function:
-
-      defmodule MyApp.DBClient do
-        @db_host Application.get_env(:my_app, :db_host, "db.local")
-
-        def start_link() do
-          SomeLib.DBClient.start_link(host: @db_host)
-        end
-      end
-
-  This approach has one big limitation: if you change the value of the
-  application environment after the code is compiled, the value used at
-  runtime is not going to change! For example, if your `config/runtime.exs`
-  has:
-
-      config :my_app, :db_host, "db.production"
-
-  This value will have no effect as the code was compiled to connect to "db.local",
-  which is mostly likely unavailable in the production environment.
-
-  For those reasons, reading the application environment at runtime should be the
-  first choice. However, if you really have to read the application environment
-  during compilation, we recommend you to use `compile_env/3` instead:
-
-      require Application
-      @db_host Application.compile_env(:my_app, :db_host, "db.local")
-
-  By using `compile_env/3`, tools like Mix will store the values used during
-  compilation and compare the compilation values with the runtime values whenever
-  your system starts, raising an error in case they differ.
-
-  ## The application callback module
-
-  Applications can be loaded, started, and stopped. Generally, build tools
-  like Mix take care of starting an application and all of its dependencies
-  for you, but you can also do it manually by calling:
-
-      {:ok, _} = Application.ensure_all_started(:some_app)
-
-  When an application starts, developers may configure a callback module
-  that executes custom code. Developers use this callback to start the
-  application supervision tree.
-
-  The first step to do so is to add a `:mod` key to the `application/0`
-  definition in your `mix.exs` file. It expects a tuple, with the application
-  callback module and start argument (commonly an empty list):
+  Often times, an application defines a supervision tree that must be started
+  and stopped when the application starts and stops. For such, we need to
+  define an application module callback. The first step is to define the
+  module callback in the application definition in the `mix.exs` file:
 
       def application do
         [mod: {MyApp, []}]
       end
 
-  The `MyApp` module given to `:mod` needs to implement the `Application` behaviour.
-  This can be done by putting `use Application` in that module and implementing the
-  `c:start/2` callback, for example:
+  Our application now requires the `MyApp` module to provide an application
+  callback. This can be done by invoking `use Application` in that module and
+  defining a `start/2` callback, for example:
 
       defmodule MyApp do
         use Application
 
         def start(_type, _args) do
-          children = []
-          Supervisor.start_link(children, strategy: :one_for_one)
+          MyApp.Supervisor.start_link()
         end
       end
 
-  The `c:start/2` callback has to spawn and link a supervisor and return `{:ok,
-  pid}` or `{:ok, pid, state}`, where `pid` is the PID of the supervisor, and
-  `state` is an optional application state. `args` is the second element of the
-  tuple given to the `:mod` option.
+  `start/2` typically returns `{:ok, pid}` or `{:ok, pid, state}` where
+  `pid` identifies the supervision tree and `state` is the application state.
+  `args` is the second element of the tuple given to the `:mod` option.
 
-  The `type` argument passed to `c:start/2` is usually `:normal` unless in a
+  The `type` argument passed to `start/2` is usually `:normal` unless in a
   distributed setup where application takeovers and failovers are configured.
-  Distributed applications are beyond the scope of this documentation.
+  This particular aspect of applications is explained in more detail in the
+  OTP documentation:
 
-  When an application is shutting down, its `c:stop/1` callback is called after
-  the supervision tree has been stopped by the runtime. This callback allows the
-  application to do any final cleanup. The argument is the state returned by
-  `c:start/2`, if it did, or `[]` otherwise. The return value of `c:stop/1` is
-  ignored.
+    * [`:application` module](http://www.erlang.org/doc/man/application.html)
+    * [Applications – OTP Design Principles](http://www.erlang.org/doc/design_principles/applications.html)
 
-  By using `Application`, modules get a default implementation of `c:stop/1`
-  that ignores its argument and returns `:ok`, but it can be overridden.
-
-  Application callback modules may also implement the optional callback
-  `c:prep_stop/1`. If present, `c:prep_stop/1` is invoked before the supervision
-  tree is terminated. Its argument is the state returned by `c:start/2`, if it did,
-  or `[]` otherwise, and its return value is passed to `c:stop/1`.
-
-  ## The application resource file
-
-  In the sections above, we have configured an application in the
-  `application/0` section of the `mix.exs` file. Ultimately, Mix will use
-  this configuration to create an [*application resource
-  file*](https://erlang.org/doc/man/application.html), which is a file called
-  `APP_NAME.app`. For example, the application resource file of the OTP
-  application `ex_unit` is called `ex_unit.app`.
-
-  You can learn more about the generation of application resource files in
-  the documentation of `Mix.Tasks.Compile.App`, available as well by running
-  `mix help compile.app`.
-
-  ## The application life cycle
-
-  ### Loading applications
-
-  Applications are *loaded*, which means that the runtime finds and processes
-  their resource files:
-
-      Application.load(:ex_unit)
-      #=> :ok
-
-  When an application is loaded, the environment specified in its resource file
-  is merged with any overrides from config files.
-
-  Loading an application *does not* load its modules.
-
-  In practice, you rarely load applications by hand because that is part of the
-  start process, explained next.
-
-  ### Starting applications
-
-  Applications are also *started*:
-
-      Application.start(:ex_unit)
-      #=> :ok
-
-  Once your application is compiled, running your system is a matter of starting
-  your current application and its dependencies. Differently from other languages,
-  Elixir does not have a `main` procedure that is responsible for starting your
-  system. Instead, you start one or more applications, each with their own
-  initialization and termination logic.
-
-  When an application is started, the `Application.load/1` is automatically
-  invoked if it hasn't been done yet. Then, it checks if the dependencies listed
-  in the `applications` key of the resource file are already started. Having at
-  least one dependency not started is an error condition. Functions like
-  `ensure_all_started/1` takes care of starting an application and all of its
-  dependencies for you.
-
-  If the application does not have a callback module configured, starting is
-  done at this point. Otherwise, its `c:start/2` callback is invoked. The PID of
-  the top-level supervisor returned by this function is stored by the runtime
-  for later use, and the returned application state is saved too, if any.
-
-  ### Stopping applications
-
-  Started applications are, finally, *stopped*:
-
-      Application.stop(:ex_unit)
-      #=> :ok
-
-  Stopping an application without a callback module is defined, but except for
-  some system tracing, it is in practice a no-op.
-
-  Stopping an application with a callback module has three steps:
-
-    1. If present, invoke the optional callback `c:prep_stop/1`.
-    2. Terminate the top-level supervisor.
-    3. Invoke the required callback `c:stop/1`.
-
-  The arguments passed to the callbacks are related to the state optionally
-  returned by `c:start/2`, and are documented in the section about the callback
-  module above.
-
-  It is important to highlight that step 2 is a blocking one. Termination of a
-  supervisor triggers a recursive chain of children terminations, therefore
-  orderly shutting down all descendant processes. The `c:stop/1` callback is
-  invoked only after termination of the whole supervision tree.
-
-  Shutting down a live system cleanly can be done by calling `System.stop/1`. It
-  will shut down every application in the opposite order they had been started.
-
-  By default, a SIGTERM from the operating system will automatically translate to
-  `System.stop/0`. You can also have more explicit control over operating system
-  signals via the `:os.set_signal/2` function.
-
-  ## Tooling
-
-  The Mix build tool automates most of the application management tasks. For example,
-  `mix test` automatically starts your application dependencies and your application
-  itself before your test runs. `mix run --no-halt` boots your current project and
-  can be used to start a long running system. See `mix help run`.
-
-  Developers can also use `mix release` to build **releases**. Releases are able to
-  package all of your source code as well as the Erlang VM into a single directory.
-  Releases also give you explicit control over how each application is started and in
-  which order. They also provide a more streamlined mechanism for starting and
-  stopping systems, debugging, logging, as well as system monitoring.
-
-  Finally, Elixir provides tools such as escripts and archives, which are
-  different mechanisms for packaging your application. Those are typically used
-  when tools must be shared between developers and not as deployment options.
-  See `mix help archive.build` and `mix help escript.build` for more detail.
-
-  ## Further information
-
-  For further details on applications please check the documentation of the
-  [`:application` Erlang module](`:application`), and the
-  [Applications](https://erlang.org/doc/design_principles/applications.html)
-  section of the [OTP Design Principles User's
-  Guide](https://erlang.org/doc/design_principles/users_guide.html).
+  A developer may also implement the `stop/1` callback (automatically defined
+  by `use Application`) which does any application cleanup. It receives the
+  application state and can return any value. Note that shutting down the
+  supervisor is automatically handled by the VM.
   """
 
   @doc """
   Called when an application is started.
 
-  This function is called when an application is started using
+  This function is called when an the application is started using
   `Application.start/2` (and functions on top of that, such as
   `Application.ensure_started/2`). This function should start the top-level
   process of the application (which should be the top supervisor of the
@@ -292,7 +104,7 @@ defmodule Application do
 
     * `:normal` - used if the startup is a normal startup or if the application
       is distributed and is started on the current node because of a failover
-      from another node and the application specification key `:start_phases`
+      from another mode and the application specification key `:start_phases`
       is `:undefined`.
     * `{:takeover, node}` - used if the application is distributed and is
       started on the current node because of a failover on the node `node`.
@@ -301,7 +113,7 @@ defmodule Application do
       application specification key `:start_phases` is not `:undefined`.
 
   `start_args` are the arguments passed to the application in the `:mod`
-  specification key (for example, `mod: {MyApp, [:my_args]}`).
+  specification key (e.g., `mod: {MyApp, [:my_args]}`).
 
   This function should either return `{:ok, pid}` or `{:ok, pid, state}` if
   startup is successful. `pid` should be the PID of the top supervisor. `state`
@@ -313,60 +125,26 @@ defmodule Application do
   callback.
   """
   @callback start(start_type, start_args :: term) ::
-              {:ok, pid}
-              | {:ok, pid, state}
-              | {:error, reason :: term}
+    {:ok, pid} |
+    {:ok, pid, state} |
+    {:error, reason :: term}
 
   @doc """
-  Called before stopping the application.
+  Called when an application is stopped.
 
-  This function is called before the top-level supervisor is terminated. It
-  receives the state returned by `c:start/2`, if it did, or `[]` otherwise.
-  The return value is later passed to `c:stop/1`.
-  """
-  @callback prep_stop(state) :: state
-
-  @doc """
-  Called after an application has been stopped.
-
-  This function is called after an application has been stopped, i.e., after its
+  This function is called when an application has stopped, i.e., when its
   supervision tree has been stopped. It should do the opposite of what the
-  `c:start/2` callback did, and should perform any necessary cleanup. The return
+  `start/2` callback did, and should perform any necessary cleanup. The return
   value of this callback is ignored.
 
-  `state` is the state returned by `c:start/2`, if it did, or `[]` otherwise.
-  If the optional callback `c:prep_stop/1` is present, `state` is its return
-  value instead.
+  `state` is the return value of the `start/2` callback or the return value of
+  the `prep_stop/1` function if the application module defines such a function.
 
   `use Application` defines a default implementation of this function which does
   nothing and just returns `:ok`.
   """
   @callback stop(state) :: term
 
-  @doc """
-  Starts an application in synchronous phases.
-
-  This function is called after `start/2` finishes but before
-  `Application.start/2` returns. It will be called once for every start phase
-  defined in the application's (and any included applications') specification,
-  in the order they are listed in.
-  """
-  @callback start_phase(phase :: term, start_type, phase_args :: term) ::
-              :ok | {:error, reason :: term}
-
-  @doc """
-  Callback invoked after code upgrade, if the application environment
-  has changed.
-
-  `changed` is a keyword list of keys and their changed values in the
-  application environment. `new` is a keyword list with all new keys
-  and their values. `removed` is a list with all removed keys.
-  """
-  @callback config_change(changed, new, removed) :: :ok
-            when changed: keyword, new: keyword, removed: [atom]
-
-  @optional_callbacks start_phase: 3, prep_stop: 1, config_change: 3
-
   @doc false
   defmacro __using__(_) do
     quote location: :keep do
@@ -377,50 +155,34 @@ defmodule Application do
         :ok
       end
 
-      defoverridable Application
+      defoverridable [stop: 1]
     end
   end
 
-  @application_keys [
-    :description,
-    :id,
-    :vsn,
-    :modules,
-    :maxP,
-    :maxT,
-    :registered,
-    :included_applications,
-    :optional_applications,
-    :applications,
-    :mod,
-    :start_phases
-  ]
-
-  application_key_specs = Enum.reduce(@application_keys, &{:|, [], [&1, &2]})
-
   @type app :: atom
   @type key :: atom
-  @type application_key :: unquote(application_key_specs)
   @type value :: term
   @type state :: term
-  @type start_type :: :normal | {:takeover, node} | {:failover, node}
-  @type restart_type :: :permanent | :transient | :temporary
+  @type start_type :: :permanent | :transient | :temporary
+
+  @application_keys [:description, :id, :vsn, :modules, :maxP, :maxT, :registered,
+                     :included_applications, :applications, :mod, :start_phases]
 
   @doc """
   Returns the spec for `app`.
 
   The following keys are returned:
 
-    * #{Enum.map_join(@application_keys, "\n  * ", &"`#{inspect(&1)}`")}
+    * #{Enum.map_join @application_keys, "\n  * ", &inspect/1}
 
   Note the environment is not returned as it can be accessed via
   `fetch_env/2`. Returns `nil` if the application is not loaded.
   """
-  @spec spec(app) :: [{application_key, value}] | nil
-  def spec(app) when is_atom(app) do
+  @spec spec(app) :: [{key, value}] | nil
+  def spec(app) do
     case :application.get_all_key(app) do
       {:ok, info} -> :lists.keydelete(:env, 1, info)
-      :undefined -> nil
+      :undefined  -> nil
     end
   end
 
@@ -431,8 +193,8 @@ defmodule Application do
   specification parameter does not exist, this function
   will raise. Returns `nil` if the application is not loaded.
   """
-  @spec spec(app, application_key) :: value | nil
-  def spec(app, key) when is_atom(app) and key in @application_keys do
+  @spec spec(app, key) :: value | nil
+  def spec(app, key) when key in @application_keys do
     case :application.get_key(app, key) do
       {:ok, value} -> value
       :undefined -> nil
@@ -458,194 +220,18 @@ defmodule Application do
   Returns all key-value pairs for `app`.
   """
   @spec get_all_env(app) :: [{key, value}]
-  def get_all_env(app) when is_atom(app) do
+  def get_all_env(app) do
     :application.get_all_env(app)
   end
 
-  @doc """
-  Reads the application environment at compilation time.
-
-  Similar to `get_env/3`, except it must be used to read values
-  at compile time. This allows Elixir to track when configuration
-  values change between compile time and runtime.
-
-  The first argument is the application name. The second argument
-  `key_or_path` is either an atom key or a path to traverse in
-  search of the configuration, starting with an atom key.
-
-  For example, imagine the following configuration:
-
-      config :my_app, :key, [foo: [bar: :baz]]
-
-  We can access it during compile time as:
-
-      Application.compile_env(:my_app, :key)
-      #=> [foo: [bar: :baz]]
-
-      Application.compile_env(:my_app, [:key, :foo])
-      #=> [bar: :baz]
-
-      Application.compile_env(:my_app, [:key, :foo, :bar])
-      #=> :baz
-
-  A default value can also be given as third argument. If
-  any of the keys in the path along the way is missing, the
-  default value is used:
-
-      Application.compile_env(:my_app, [:unknown, :foo, :bar], :default)
-      #=> :default
-
-      Application.compile_env(:my_app, [:key, :unknown, :bar], :default)
-      #=> :default
-
-      Application.compile_env(:my_app, [:key, :foo, :unknown], :default)
-      #=> :default
-
-  Giving a path is useful to let Elixir know that only certain paths
-  in a large configuration are compile time dependent.
-  """
-  # TODO: Warn on v1.14 if get_env/fetch_env/fetch_env! is used at
-  # compile time instead of compile_env
-  @doc since: "1.10.0"
-  @spec compile_env(app, key | list, value) :: value
-  defmacro compile_env(app, key_or_path, default \\ nil) do
-    if __CALLER__.function do
-      raise "Application.compile_env/3 cannot be called inside functions, only in the module body"
-    end
-
-    key_or_path = expand_key_or_path(key_or_path, __CALLER__)
-
-    quote do
-      Application.__compile_env__(unquote(app), unquote(key_or_path), unquote(default), __ENV__)
-    end
-  end
-
-  defp expand_key_or_path({:__aliases__, _, _} = alias, env),
-    do: Macro.expand(alias, %{env | function: {:__info__, 1}})
-
-  defp expand_key_or_path(list, env) when is_list(list),
-    do: Enum.map(list, &expand_key_or_path(&1, env))
-
-  defp expand_key_or_path(other, _env),
-    do: other
-
-  @doc false
-  def __compile_env__(app, key_or_path, default, env) do
-    case fetch_compile_env(app, key_or_path, env) do
-      {:ok, value} -> value
-      :error -> default
-    end
-  end
-
-  @doc """
-  Reads the application environment at compilation time or raises.
-
-  This is the same as `compile_env/3` but it raises an
-  `ArgumentError` if the configuration is not available.
-  """
-  @doc since: "1.10.0"
-  @spec compile_env!(app, key | list) :: value
-  defmacro compile_env!(app, key_or_path) do
-    if __CALLER__.function do
-      raise "Application.compile_env!/2 cannot be called inside functions, only in the module body"
-    end
-
-    key_or_path = expand_key_or_path(key_or_path, __CALLER__)
-
-    quote do
-      Application.__compile_env__!(unquote(app), unquote(key_or_path), __ENV__)
-    end
-  end
-
-  @doc false
-  def __compile_env__!(app, key_or_path, env) do
-    case fetch_compile_env(app, key_or_path, env) do
-      {:ok, value} ->
-        value
-
-      :error ->
-        raise ArgumentError,
-              "could not fetch application environment #{inspect(key_or_path)} for application " <>
-                "#{inspect(app)} #{fetch_env_failed_reason(app, key_or_path)}"
-    end
-  end
-
-  defp fetch_compile_env(app, key, env) when is_atom(key),
-    do: fetch_compile_env(app, key, [], env)
-
-  defp fetch_compile_env(app, [key | paths], env) when is_atom(key),
-    do: fetch_compile_env(app, key, paths, env)
-
-  defp fetch_compile_env(app, key, path, env) do
-    return = traverse_env(fetch_env(app, key), path)
-
-    for tracer <- env.tracers do
-      tracer.trace({:compile_env, app, [key | path], return}, env)
-    end
-
-    return
-  end
-
-  defp traverse_env(return, []), do: return
-  defp traverse_env(:error, _paths), do: :error
-  defp traverse_env({:ok, value}, [key | keys]), do: traverse_env(Access.fetch(value, key), keys)
-
   @doc """
   Returns the value for `key` in `app`'s environment.
 
   If the configuration parameter does not exist, the function returns the
   `default` value.
-
-  **Important:** if you are reading the application environment at compilation
-  time, for example, inside the module definition instead of inside of a
-  function, see `compile_env/3` instead.
-
-  **Important:** if you are writing a library to be used by other developers,
-  it is generally recommended to avoid the application environment, as the
-  application environment is effectively a global storage. For more information,
-  read our [library guidelines](library-guidelines.md).
-
-  ## Examples
-
-  `get_env/3` is commonly used to read the configuration of your OTP applications.
-  Since Mix configurations are commonly used to configure applications, we will use
-  this as a point of illustration.
-
-  Consider a new application `:my_app`. `:my_app` contains a database engine which
-  supports a pool of databases. The database engine needs to know the configuration for
-  each of those databases, and that configuration is supplied by key-value pairs in
-  environment of `:my_app`.
-
-      config :my_app, Databases.RepoOne,
-        # A database configuration
-        ip: "localhost",
-        port: 5433
-
-      config :my_app, Databases.RepoTwo,
-        # Another database configuration (for the same OTP app)
-        ip: "localhost",
-        port: 20717
-
-      config :my_app, my_app_databases: [Databases.RepoOne, Databases.RepoTwo]
-
-  Our database engine used by `:my_app` needs to know what databases exist, and
-  what the database configurations are. The database engine can make a call to
-  `Application.get_env(:my_app, :my_app_databases, [])` to retrieve the list of
-  databases (specified by module names).
-
-  The engine can then traverse each repository in the list and call
-  `Application.get_env(:my_app, Databases.RepoOne)` and so forth to retrieve the
-  configuration of each one. In this case, each configuration will be a keyword
-  list, so you can use the functions in the `Keyword` module or even the `Access`
-  module to traverse it, for example:
-
-      config = Application.get_env(:my_app, Databases.RepoOne)
-      config[:ip]
-
   """
   @spec get_env(app, key, value) :: value
-  def get_env(app, key, default \\ nil) when is_atom(app) do
-    maybe_warn_on_app_env_key(app, key)
+  def get_env(app, key, default \\ nil) do
     :application.get_env(app, key, default)
   end
 
@@ -655,9 +241,7 @@ defmodule Application do
   If the configuration parameter does not exist, the function returns `:error`.
   """
   @spec fetch_env(app, key) :: {:ok, value} | :error
-  def fetch_env(app, key) when is_atom(app) do
-    maybe_warn_on_app_env_key(app, key)
-
+  def fetch_env(app, key) do
     case :application.get_env(app, key) do
       {:ok, value} -> {:ok, value}
       :undefined -> :error
@@ -668,33 +252,15 @@ defmodule Application do
   Returns the value for `key` in `app`'s environment.
 
   If the configuration parameter does not exist, raises `ArgumentError`.
-
-  **Important:** if you are reading the application environment at compilation
-  time, for example, inside the module definition instead of inside of a
-  function, see `compile_env!/2` instead.
   """
-  @spec fetch_env!(app, key) :: value
-  def fetch_env!(app, key) when is_atom(app) do
+  @spec fetch_env!(app, key) :: value | no_return
+  def fetch_env!(app, key) do
     case fetch_env(app, key) do
-      {:ok, value} ->
-        value
-
+      {:ok, value} -> value
       :error ->
         raise ArgumentError,
-              "could not fetch application environment #{inspect(key)} for application " <>
-                "#{inspect(app)} #{fetch_env_failed_reason(app, key)}"
-    end
-  end
-
-  defp fetch_env_failed_reason(app, key) do
-    vsn = :application.get_key(app, :vsn)
-
-    case vsn do
-      {:ok, _} ->
-        "because configuration at #{inspect(key)} was not set"
-
-      :undefined ->
-        "because the application was not loaded nor configured"
+          "application #{inspect app} is not loaded, " <>
+          "or the configuration parameter #{inspect key} is not set"
     end
   end
 
@@ -703,62 +269,33 @@ defmodule Application do
 
   ## Options
 
-    * `:timeout` - the timeout for the change (defaults to `5_000` milliseconds)
+    * `:timeout`    - the timeout for the change (defaults to 5000ms)
     * `:persistent` - persists the given value on application load and reloads
 
   If `put_env/4` is called before the application is loaded, the application
   environment values specified in the `.app` file will override the ones
   previously set.
 
-  The `:persistent` option can be set to `true` when there is a need to guarantee
+  The persistent option can be set to `true` when there is a need to guarantee
   parameters set with this function will not be overridden by the ones defined
   in the application resource file on load. This means persistent values will
   stick after the application is loaded and also on application reload.
   """
-  @spec put_env(app, key, value, timeout: timeout, persistent: boolean) :: :ok
-  def put_env(app, key, value, opts \\ []) when is_atom(app) do
-    maybe_warn_on_app_env_key(app, key)
+  @spec put_env(app, key, value, [timeout: timeout, persistent: boolean]) :: :ok
+  def put_env(app, key, value, opts \\ []) do
     :application.set_env(app, key, value, opts)
   end
 
-  @doc """
-  Puts the environment for multiple apps at the same time.
-
-  The given config should not:
-
-    * have the same application listed more than once
-    * have the same key inside the same application listed more than once
-
-  If those conditions are not met, it will raise.
-
-  It receives the same options as `put_env/4`. Returns `:ok`.
-  """
-  @doc since: "1.9.0"
-  @spec put_all_env([{app, [{key, value}]}], timeout: timeout, persistent: boolean) :: :ok
-  def put_all_env(config, opts \\ []) when is_list(config) and is_list(opts) do
-    :application.set_env(config, opts)
-  end
-
   @doc """
   Deletes the `key` from the given `app` environment.
 
-  It receives the same options as `put_env/4`. Returns `:ok`.
+  See `put_env/4` for a description of the options.
   """
-  @spec delete_env(app, key, timeout: timeout, persistent: boolean) :: :ok
-  def delete_env(app, key, opts \\ []) when is_atom(app) do
-    maybe_warn_on_app_env_key(app, key)
+  @spec delete_env(app, key, [timeout: timeout, persistent: boolean]) :: :ok
+  def delete_env(app, key, opts \\ []) do
     :application.unset_env(app, key, opts)
   end
 
-  defp maybe_warn_on_app_env_key(_app, key) when is_atom(key),
-    do: :ok
-
-  # TODO: Remove this deprecation warning on 2.0+ and allow list lookups as in compile_env.
-  defp maybe_warn_on_app_env_key(app, key) do
-    message = "passing non-atom as application env key is deprecated, got: #{inspect(key)}"
-    IO.warn_once({Application, :key, app, key}, message, _stacktrace_drop_levels = 2)
-  end
-
   @doc """
   Ensures the given `app` is started.
 
@@ -769,27 +306,11 @@ defmodule Application do
       :ok = Application.ensure_started(:my_test_dep)
 
   """
-  @spec ensure_started(app, restart_type) :: :ok | {:error, term}
+  @spec ensure_started(app, start_type) :: :ok | {:error, term}
   def ensure_started(app, type \\ :temporary) when is_atom(app) do
     :application.ensure_started(app, type)
   end
 
-  @doc """
-  Ensures the given `app` is loaded.
-
-  Same as `load/2` but returns `:ok` if the application was already
-  loaded.
-  """
-  @doc since: "1.10.0"
-  @spec ensure_loaded(app) :: :ok | {:error, term}
-  def ensure_loaded(app) when is_atom(app) do
-    case :application.load(app) do
-      :ok -> :ok
-      {:error, {:already_loaded, ^app}} -> :ok
-      {:error, _} = error -> error
-    end
-  end
-
   @doc """
   Ensures the given `app` and its applications are started.
 
@@ -797,7 +318,7 @@ defmodule Application do
   `:applications` in the `.app` file in case they were not previously
   started.
   """
-  @spec ensure_all_started(app, restart_type) :: {:ok, [app]} | {:error, {app, term}}
+  @spec ensure_all_started(app, start_type) :: {:ok, [app]} | {:error, {app, term}}
   def ensure_all_started(app, type \\ :temporary) when is_atom(app) do
     :application.ensure_all_started(app, type)
   end
@@ -813,7 +334,7 @@ defmodule Application do
   started before this application is. If not, `{:error, {:not_started, app}}` is
   returned, where `app` is the name of the missing application.
 
-  In case you want to automatically load **and start** all of `app`'s dependencies,
+  In case you want to automatically  load **and start** all of `app`'s dependencies,
   see `ensure_all_started/2`.
 
   The `type` argument specifies the type of the application:
@@ -836,7 +357,7 @@ defmodule Application do
   Note also that the `:transient` type is of little practical use, since when a
   supervision tree terminates, the reason is set to `:shutdown`, not `:normal`.
   """
-  @spec start(app, restart_type) :: :ok | {:error, term}
+  @spec start(app, start_type) :: :ok | {:error, term}
   def start(app, type \\ :temporary) when is_atom(app) do
     :application.start(app, type)
   end
@@ -847,7 +368,7 @@ defmodule Application do
   When stopped, the application is still loaded.
   """
   @spec stop(app) :: :ok | {:error, term}
-  def stop(app) when is_atom(app) do
+  def stop(app) do
     :application.stop(app)
   end
 
@@ -898,50 +419,31 @@ defmodule Application do
       #=> "bar-123"
 
   For more information on code paths, check the `Code` module in
-  Elixir and also Erlang's [`:code` module](`:code`).
+  Elixir and also Erlang's `:code` module.
   """
-  @spec app_dir(app) :: String.t()
+  @spec app_dir(app) :: String.t
   def app_dir(app) when is_atom(app) do
     case :code.lib_dir(app) do
       lib when is_list(lib) -> IO.chardata_to_string(lib)
-      {:error, :bad_name} -> raise ArgumentError, "unknown application: #{inspect(app)}"
+      {:error, :bad_name} -> raise ArgumentError, "unknown application: #{inspect app}"
     end
   end
 
   @doc """
   Returns the given path inside `app_dir/1`.
-
-  If `path` is a string, then it will be used as the path inside `app_dir/1`. If
-  `path` is a list of strings, it will be joined (see `Path.join/1`) and the result
-  will be used as the path inside `app_dir/1`.
-
-  ## Examples
-
-      File.mkdir_p!("foo/ebin")
-      Code.prepend_path("foo/ebin")
-
-      Application.app_dir(:foo, "my_path")
-      #=> "foo/my_path"
-
-      Application.app_dir(:foo, ["my", "nested", "path"])
-      #=> "foo/my/nested/path"
-
   """
-  @spec app_dir(app, String.t() | [String.t()]) :: String.t()
-  def app_dir(app, path)
-
-  def app_dir(app, path) when is_atom(app) and is_binary(path) do
+  @spec app_dir(app, String.t | [String.t]) :: String.t
+  def app_dir(app, path) when is_binary(path) do
     Path.join(app_dir(app), path)
   end
-
-  def app_dir(app, path) when is_atom(app) and is_list(path) do
+  def app_dir(app, path) when is_list(path) do
     Path.join([app_dir(app) | path])
   end
 
   @doc """
   Returns a list with information about the applications which are currently running.
   """
-  @spec started_applications(timeout) :: [{app, description :: charlist(), vsn :: charlist()}]
+  @spec started_applications(timeout) :: [tuple]
   def started_applications(timeout \\ 5000) do
     :application.which_applications(timeout)
   end
@@ -949,9 +451,9 @@ defmodule Application do
   @doc """
   Returns a list with information about the applications which have been loaded.
   """
-  @spec loaded_applications :: [{app, description :: charlist(), vsn :: charlist()}]
+  @spec loaded_applications :: [tuple]
   def loaded_applications do
-    :application.loaded_applications()
+    :application.loaded_applications
   end
 
   @doc """
@@ -959,7 +461,7 @@ defmodule Application do
   `ensure_started/2`, `stop/1`, `load/1` and `unload/1`,
   returns a string.
   """
-  @spec format_error(any) :: String.t()
+  @spec format_error(any) :: String.t
   def format_error(reason) do
     try do
       do_format_error(reason)
@@ -978,8 +480,8 @@ defmodule Application do
 
   # {:error, reason} return value
   defp do_format_error({reason, {mod, :start, args}}) do
-    Exception.format_mfa(mod, :start, args) <>
-      " returned an error: " <> Exception.format_exit(reason)
+    Exception.format_mfa(mod, :start, args) <> " returned an error: " <>
+      Exception.format_exit(reason)
   end
 
   # error or exit(reason) call, use exit reason as reason.
@@ -989,7 +491,8 @@ defmodule Application do
 
   # bad return value
   defp do_format_error({:bad_return, {{mod, :start, args}, return}}) do
-    Exception.format_mfa(mod, :start, args) <> " returned a bad value: " <> inspect(return)
+    Exception.format_mfa(mod, :start, args) <>
+      " returned a bad value: " <> inspect(return)
   end
 
   defp do_format_error({:already_started, app}) when is_atom(app) do

lib/elixir/lib/atom.ex

@@ -1,46 +1,8 @@
 defmodule Atom do
   @moduledoc """
-  Atoms are constants whose values are their own name.
-
-  They are often useful to enumerate over distinct values, such as:
-
-      iex> :apple
-      :apple
-      iex> :orange
-      :orange
-      iex> :watermelon
-      :watermelon
-
-  Atoms are equal if their names are equal.
-
-      iex> :apple == :apple
-      true
-      iex> :apple == :orange
-      false
-
-  Often they are used to express the state of an operation, by using
-  values such as `:ok` and `:error`.
-
-  The booleans `true` and `false` are also atoms:
-
-      iex> true == :true
-      true
-      iex> is_atom(false)
-      true
-      iex> is_boolean(:false)
-      true
-
-  Elixir allows you to skip the leading `:` for the atoms `false`, `true`,
-  and `nil`.
-
-  Atoms must be composed of Unicode characters such as letters, numbers,
-  underscore, and `@`. If the keyword has a character that does not
-  belong to the category above, such as spaces, you can wrap it in
-  quotes:
-
-      iex> :"this is an atom with spaces"
-      :"this is an atom with spaces"
+  Convenience functions for working with atoms.
 
+  See also `Kernel.is_atom/1`.
   """
 
   @doc """
@@ -54,7 +16,7 @@ defmodule Atom do
       "foo"
 
   """
-  @spec to_string(atom) :: String.t()
+  @spec to_string(atom) :: String.t
   def to_string(atom) do
     :erlang.atom_to_binary(atom, :utf8)
   end
@@ -75,8 +37,8 @@ defmodule Atom do
     :erlang.atom_to_list(atom)
   end
 
+  # TODO: Deprecate by v1.5
   @doc false
-  @deprecated "Use Atom.to_charlist/1 instead"
   @spec to_char_list(atom) :: charlist
   def to_char_list(atom), do: Atom.to_charlist(atom)
 end

lib/elixir/lib/behaviour.ex

@@ -1,23 +1,18 @@
 defmodule Behaviour do
   @moduledoc """
-  Mechanism for handling behaviours.
+  This module has been deprecated.
 
-  This module is deprecated. Instead of `defcallback/1` and
-  `defmacrocallback/1`, the `@callback` and `@macrocallback`
-  module attributes can be used respectively. See the
-  documentation for `Module` for more information on these
-  attributes.
+  Instead of `defcallback/1` and `defmacrocallback/1`, the `@callback` and
+  `@macrocallback` module attributes can be used (respectively). See the
+  documentation for `Module` for more information on these attributes.
 
   Instead of `MyModule.__behaviour__(:callbacks)`,
   `MyModule.behaviour_info(:callbacks)` can be used.
   """
 
-  @moduledoc deprecated: "Use @callback and @macrocallback attributes instead"
-
   @doc """
   Defines a function callback according to the given type specification.
   """
-  @deprecated "Use the @callback module attribute instead"
   defmacro defcallback(spec) do
     do_defcallback(:def, split_spec(spec, quote(do: term)))
   end
@@ -25,12 +20,11 @@ defmodule Behaviour do
   @doc """
   Defines a macro callback according to the given type specification.
   """
-  @deprecated "Use the @macrocallback module attribute instead"
   defmacro defmacrocallback(spec) do
-    do_defcallback(:defmacro, split_spec(spec, quote(do: Macro.t())))
+    do_defcallback(:defmacro, split_spec(spec, quote(do: Macro.t)))
   end
 
-  defp split_spec({:when, _, [{:"::", _, [spec, return]}, guard]}, _default) do
+  defp split_spec({:when, _, [{:::, _, [spec, return]}, guard]}, _default) do
     {spec, return, guard}
   end
 
@@ -38,7 +32,7 @@ defmodule Behaviour do
     {spec, default, guard}
   end
 
-  defp split_spec({:"::", _, [spec, return]}, _default) do
+  defp split_spec({:::, _, [spec, return]}, _default) do
     {spec, return, []}
   end
 
@@ -50,25 +44,21 @@ defmodule Behaviour do
     case Macro.decompose_call(spec) do
       {name, args} ->
         do_callback(kind, name, args, return, guards)
-
       _ ->
         raise ArgumentError, "invalid syntax in #{kind}callback #{Macro.to_string(spec)}"
     end
   end
 
   defp do_callback(kind, name, args, return, guards) do
-    fun = fn
-      {:"::", _, [left, right]} ->
+    :lists.foreach fn
+      {:::, _, [left, right]} ->
         ensure_not_default(left)
         ensure_not_default(right)
         left
-
       other ->
         ensure_not_default(other)
         other
-    end
-
-    :lists.foreach(fun, args)
+    end, args
 
     spec =
       quote do
@@ -76,8 +66,8 @@ defmodule Behaviour do
       end
 
     case kind do
-      :def -> quote(do: @callback(unquote(spec)))
-      :defmacro -> quote(do: @macrocallback(unquote(spec)))
+      :def -> quote(do: @callback unquote(spec))
+      :defmacro -> quote(do: @macrocallback unquote(spec))
     end
   end
 
@@ -92,9 +82,8 @@ defmodule Behaviour do
     quote do
       warning =
         "the Behaviour module is deprecated. Instead of using this module, " <>
-          "use the @callback and @macrocallback module attributes. See the " <>
-          "documentation for Module for more information on these attributes"
-
+        "use the @callback and @macrocallback module attributes. See the " <>
+        "documentation for Module for more information on these attributes"
       IO.warn(warning)
 
       @doc false
@@ -103,20 +92,14 @@ defmodule Behaviour do
       end
 
       def __behaviour__(:docs) do
-        {:docs_v1, _, :elixir, _, _, _, docs} = Code.fetch_docs(__MODULE__)
-
-        for {{kind, name, arity}, line, _, doc, _} <- docs, kind in [:callback, :macrocallback] do
+        for {tuple, line, kind, docs} <- Code.get_docs(__MODULE__, :callback_docs) do
           case kind do
-            :callback -> {{name, arity}, line, :def, __behaviour__doc_value(doc)}
-            :macrocallback -> {{name, arity}, line, :defmacro, __behaviour__doc_value(doc)}
+            :callback -> {tuple, line, :def, docs}
+            :macrocallback -> {tuple, line, :defmacro, docs}
           end
         end
       end
 
-      defp __behaviour__doc_value(%{"en" => doc}), do: doc
-      defp __behaviour__doc_value(:hidden), do: false
-      defp __behaviour__doc_value(_), do: nil
-
       import unquote(__MODULE__)
     end
   end

lib/elixir/lib/bitwise.ex

@@ -1,17 +1,14 @@
 defmodule Bitwise do
   @moduledoc """
-  A set of functions that perform calculations on bits.
+  A set of macros that perform calculations on bits.
 
-  All bitwise functions work only on integers; otherwise an
-  `ArithmeticError` is raised.
-
-  The functions in this module come in two flavors: named or
+  The macros in this module come in two flavors: named or
   operators. For example:
 
       iex> use Bitwise
-      iex> bnot(1) # named
+      iex> bnot 1   # named
       -2
-      iex> 1 &&& 1 # operator
+      iex> 1 &&& 1  # operator
       1
 
   If you prefer to use only operators or skip them, you can
@@ -29,31 +26,25 @@ defmodule Bitwise do
   When invoked with no options, `use Bitwise` is equivalent
   to `import Bitwise`.
 
-  All bitwise functions can be used in guards:
+  All bitwise macros can be used in guards:
 
-      iex> odd? = fn
-      ...>   int when Bitwise.band(int, 1) == 1 -> true
-      ...>   _ -> false
-      ...> end
+      iex> use Bitwise
+      iex> odd? = fn int when band(int, 1) == 1 -> true; _ -> false end
       iex> odd?.(1)
       true
 
-  All functions in this module are inlined by the compiler.
   """
 
   @doc false
   defmacro __using__(options) do
-    except =
-      cond do
-        Keyword.get(options, :only_operators) ->
-          [bnot: 1, band: 2, bor: 2, bxor: 2, bsl: 2, bsr: 2]
-
-        Keyword.get(options, :skip_operators) ->
-          [~~~: 1, &&&: 2, |||: 2, ^^^: 2, <<<: 2, >>>: 2]
-
-        true ->
-          []
-      end
+    except = cond do
+      Keyword.get(options, :only_operators) ->
+        [bnot: 1, band: 2, bor: 2, bxor: 2, bsl: 2, bsr: 2]
+      Keyword.get(options, :skip_operators) ->
+        [~~~: 1, &&&: 2, |||: 2, ^^^: 2, <<<: 2, >>>: 2]
+      true ->
+        []
+    end
 
     quote do
       import Bitwise, except: unquote(except)
@@ -61,246 +52,162 @@ defmodule Bitwise do
   end
 
   @doc """
-  Calculates the bitwise NOT of the argument.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Calculates the bitwise NOT of its argument.
 
       iex> bnot(2)
       -3
-
       iex> bnot(2) &&& 3
       1
 
   """
-  @doc guard: true
-  @spec bnot(integer) :: integer
-  def bnot(expr) do
-    :erlang.bnot(expr)
+  defmacro bnot(expr) do
+    quote do: :erlang.bnot(unquote(expr))
   end
 
   @doc """
-  Bitwise NOT unary operator.
-
-  Calculates the bitwise NOT of the argument.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Prefix (unary) operator; calculates the bitwise NOT of its argument.
 
       iex> ~~~2
       -3
-
       iex> ~~~2 &&& 3
       1
 
   """
-  @doc guard: true
-  @spec ~~~integer :: integer
-  def ~~~expr do
-    :erlang.bnot(expr)
+  defmacro ~~~expr do
+    quote do: :erlang.bnot(unquote(expr))
   end
 
   @doc """
   Calculates the bitwise AND of its arguments.
 
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
-
       iex> band(9, 3)
       1
 
   """
-  @doc guard: true
-  @spec band(integer, integer) :: integer
-  def band(left, right) do
-    :erlang.band(left, right)
+  defmacro band(left, right) do
+    quote do: :erlang.band(unquote(left), unquote(right))
   end
 
   @doc """
-  Bitwise AND operator.
-
-  Calculates the bitwise AND of its arguments.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Infix operator; calculates the bitwise AND of its arguments.
 
       iex> 9 &&& 3
       1
 
   """
-  @doc guard: true
-  @spec integer &&& integer :: integer
-  def left &&& right do
-    :erlang.band(left, right)
+  defmacro left &&& right do
+    quote do: :erlang.band(unquote(left), unquote(right))
   end
 
   @doc """
   Calculates the bitwise OR of its arguments.
 
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
-
       iex> bor(9, 3)
       11
 
   """
-  @doc guard: true
-  @spec bor(integer, integer) :: integer
-  def bor(left, right) do
-    :erlang.bor(left, right)
+  defmacro bor(left, right) do
+    quote do: :erlang.bor(unquote(left), unquote(right))
   end
 
   @doc """
-  Bitwise OR operator.
-
-  Calculates the bitwise OR of its arguments.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Infix operator; calculates the bitwise OR of its arguments.
 
       iex> 9 ||| 3
       11
 
   """
-  @doc guard: true
-  @spec integer ||| integer :: integer
-  def left ||| right do
-    :erlang.bor(left, right)
+  defmacro left ||| right do
+    quote do: :erlang.bor(unquote(left), unquote(right))
   end
 
   @doc """
   Calculates the bitwise XOR of its arguments.
 
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
-
       iex> bxor(9, 3)
       10
 
   """
-  @doc guard: true
-  @spec bxor(integer, integer) :: integer
-  def bxor(left, right) do
-    :erlang.bxor(left, right)
+  defmacro bxor(left, right) do
+    quote do: :erlang.bxor(unquote(left), unquote(right))
   end
 
-  @doc false
-  def unquote(:^^^)(left, right) do
-    :erlang.bxor(left, right)
+  @doc """
+  Infix operator; calculates the bitwise XOR of its arguments.
+
+      iex> 9 ^^^ 3
+      10
+
+  """
+  defmacro left ^^^ right do
+    quote do: :erlang.bxor(unquote(left), unquote(right))
   end
 
   @doc """
   Calculates the result of an arithmetic left bitshift.
 
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
-
       iex> bsl(1, 2)
       4
-
       iex> bsl(1, -2)
       0
-
       iex> bsl(-1, 2)
       -4
-
       iex> bsl(-1, -2)
       -1
 
   """
-  @doc guard: true
-  @spec bsl(integer, integer) :: integer
-  def bsl(left, right) do
-    :erlang.bsl(left, right)
+  defmacro bsl(left, right) do
+    quote do: :erlang.bsl(unquote(left), unquote(right))
   end
 
   @doc """
-  Arithmetic left bitshift operator.
-
-  Calculates the result of an arithmetic left bitshift.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Infix operator; calculates the result of an arithmetic left bitshift.
 
       iex> 1 <<< 2
       4
-
       iex> 1 <<< -2
       0
-
       iex> -1 <<< 2
       -4
-
       iex> -1 <<< -2
       -1
 
   """
-  @doc guard: true
-  @spec integer <<< integer :: integer
-  def left <<< right do
-    :erlang.bsl(left, right)
+  defmacro left <<< right do
+    quote do: :erlang.bsl(unquote(left), unquote(right))
   end
 
   @doc """
   Calculates the result of an arithmetic right bitshift.
 
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
-
       iex> bsr(1, 2)
       0
-
       iex> bsr(1, -2)
       4
-
       iex> bsr(-1, 2)
       -1
-
       iex> bsr(-1, -2)
       -4
 
   """
-  @doc guard: true
-  @spec bsr(integer, integer) :: integer
-  def bsr(left, right) do
-    :erlang.bsr(left, right)
+  defmacro bsr(left, right) do
+    quote do: :erlang.bsr(unquote(left), unquote(right))
   end
 
   @doc """
-  Arithmetic right bitshift operator.
-
-  Calculates the result of an arithmetic right bitshift.
-
-  Allowed in guard tests. Inlined by the compiler.
-
-  ## Examples
+  Infix operator; calculates the result of an arithmetic right bitshift.
 
       iex> 1 >>> 2
       0
-
       iex> 1 >>> -2
       4
-
       iex> -1 >>> 2
       -1
-
       iex> -1 >>> -2
       -4
 
   """
-  @doc guard: true
-  @spec integer >>> integer :: integer
-  def left >>> right do
-    :erlang.bsr(left, right)
+  defmacro left >>> right do
+    quote do: :erlang.bsr(unquote(left), unquote(right))
   end
 end

lib/elixir/lib/calendar/date_range.ex

@@ -1,227 +0,0 @@
-defmodule Date.Range do
-  @moduledoc """
-  Returns an inclusive range between dates.
-
-  Ranges must be created with the `Date.range/2` or `Date.range/3` function.
-
-  The following fields are public:
-
-    * `:first` - the initial date on the range
-    * `:last` - the last date on the range
-    * `:step` - (since v1.12.0) the step
-
-  The remaining fields are private and should not be accessed.
-  """
-
-  @type t :: %__MODULE__{
-          first: Date.t(),
-          last: Date.t(),
-          first_in_iso_days: iso_days(),
-          last_in_iso_days: iso_days(),
-          step: pos_integer | neg_integer
-        }
-
-  @typep iso_days() :: Calendar.iso_days()
-
-  @enforce_keys [:first, :last, :first_in_iso_days, :last_in_iso_days, :step]
-  defstruct [:first, :last, :first_in_iso_days, :last_in_iso_days, :step]
-
-  defimpl Enumerable do
-    def member?(
-          %Date.Range{
-            first: %{calendar: calendar},
-            first_in_iso_days: first_days,
-            last_in_iso_days: last_days,
-            step: step
-          } = range,
-          %Date{calendar: calendar} = date
-        ) do
-      {days, _} = Date.to_iso_days(date)
-
-      cond do
-        empty?(range) ->
-          {:ok, false}
-
-        first_days <= last_days ->
-          {:ok, first_days <= days and days <= last_days and rem(days - first_days, step) == 0}
-
-        true ->
-          {:ok, last_days <= days and days <= first_days and rem(days - first_days, step) == 0}
-      end
-    end
-
-    def member?(%Date.Range{step: _}, _) do
-      {:ok, false}
-    end
-
-    # TODO: Remove me on v2.0
-    def member?(
-          %{__struct__: Date.Range, first_in_iso_days: first_days, last_in_iso_days: last_days} =
-            date_range,
-          date
-        ) do
-      step = if first_days <= last_days, do: 1, else: -1
-      member?(Map.put(date_range, :step, step), date)
-    end
-
-    def count(range) do
-      {:ok, size(range)}
-    end
-
-    def slice(
-          %Date.Range{
-            first_in_iso_days: first,
-            first: %{calendar: calendar},
-            step: step
-          } = range
-        ) do
-      {:ok, size(range), &slice(first + &1 * step, step, &2, calendar)}
-    end
-
-    # TODO: Remove me on v2.0
-    def slice(
-          %{__struct__: Date.Range, first_in_iso_days: first_days, last_in_iso_days: last_days} =
-            date_range
-        ) do
-      step = if first_days <= last_days, do: 1, else: -1
-      slice(Map.put(date_range, :step, step))
-    end
-
-    defp slice(current, _step, 1, calendar) do
-      [date_from_iso_days(current, calendar)]
-    end
-
-    defp slice(current, step, remaining, calendar) do
-      [
-        date_from_iso_days(current, calendar)
-        | slice(current + step, step, remaining - 1, calendar)
-      ]
-    end
-
-    def reduce(
-          %Date.Range{
-            first_in_iso_days: first_days,
-            last_in_iso_days: last_days,
-            first: %{calendar: calendar},
-            step: step
-          },
-          acc,
-          fun
-        ) do
-      reduce(first_days, last_days, acc, fun, step, calendar)
-    end
-
-    # TODO: Remove me on v2.0
-    def reduce(
-          %{__struct__: Date.Range, first_in_iso_days: first_days, last_in_iso_days: last_days} =
-            date_range,
-          acc,
-          fun
-        ) do
-      step = if first_days <= last_days, do: 1, else: -1
-      reduce(Map.put(date_range, :step, step), acc, fun)
-    end
-
-    defp reduce(_first_days, _last_days, {:halt, acc}, _fun, _step, _calendar) do
-      {:halted, acc}
-    end
-
-    defp reduce(first_days, last_days, {:suspend, acc}, fun, step, calendar) do
-      {:suspended, acc, &reduce(first_days, last_days, &1, fun, step, calendar)}
-    end
-
-    defp reduce(first_days, last_days, {:cont, acc}, fun, step, calendar)
-         when step > 0 and first_days <= last_days
-         when step < 0 and first_days >= last_days do
-      reduce(
-        first_days + step,
-        last_days,
-        fun.(date_from_iso_days(first_days, calendar), acc),
-        fun,
-        step,
-        calendar
-      )
-    end
-
-    defp reduce(_, _, {:cont, acc}, _fun, _step, _calendar) do
-      {:done, acc}
-    end
-
-    defp date_from_iso_days(days, Calendar.ISO) do
-      {year, month, day} = Calendar.ISO.date_from_iso_days(days)
-      %Date{year: year, month: month, day: day, calendar: Calendar.ISO}
-    end
-
-    defp date_from_iso_days(days, calendar) do
-      {year, month, day, _, _, _, _} =
-        calendar.naive_datetime_from_iso_days({days, {0, 86_400_000_000}})
-
-      %Date{year: year, month: month, day: day, calendar: calendar}
-    end
-
-    defp size(%Date.Range{first_in_iso_days: first_days, last_in_iso_days: last_days, step: step})
-         when step > 0 and first_days > last_days,
-         do: 0
-
-    defp size(%Date.Range{first_in_iso_days: first_days, last_in_iso_days: last_days, step: step})
-         when step < 0 and first_days < last_days,
-         do: 0
-
-    defp size(%Date.Range{first_in_iso_days: first_days, last_in_iso_days: last_days, step: step}),
-      do: abs(div(last_days - first_days, step)) + 1
-
-    # TODO: Remove me on v2.0
-    defp size(
-           %{__struct__: Date.Range, first_in_iso_days: first_days, last_in_iso_days: last_days} =
-             date_range
-         ) do
-      step = if first_days <= last_days, do: 1, else: -1
-      size(Map.put(date_range, :step, step))
-    end
-
-    defp empty?(%Date.Range{
-           first_in_iso_days: first_days,
-           last_in_iso_days: last_days,
-           step: step
-         })
-         when step > 0 and first_days > last_days,
-         do: true
-
-    defp empty?(%Date.Range{
-           first_in_iso_days: first_days,
-           last_in_iso_days: last_days,
-           step: step
-         })
-         when step < 0 and first_days < last_days,
-         do: true
-
-    defp empty?(%Date.Range{step: _}), do: false
-
-    # TODO: Remove me on v2.0
-    defp empty?(
-           %{__struct__: Date.Range, first_in_iso_days: first_days, last_in_iso_days: last_days} =
-             date_range
-         ) do
-      step = if first_days <= last_days, do: 1, else: -1
-      empty?(Map.put(date_range, :step, step))
-    end
-  end
-
-  defimpl Inspect do
-    import Kernel, except: [inspect: 2]
-
-    def inspect(%Date.Range{first: first, last: last, step: 1}, _) do
-      "#DateRange<" <> inspect(first) <> ", " <> inspect(last) <> ">"
-    end
-
-    def inspect(%Date.Range{first: first, last: last, step: step}, _) do
-      "#DateRange<" <> inspect(first) <> ", " <> inspect(last) <> ", #{step}>"
-    end
-
-    # TODO: Remove me on v2.0
-    def inspect(%{__struct__: Date.Range, first: first, last: last} = date_range, opts) do
-      step = if first <= last, do: 1, else: -1
-      inspect(Map.put(date_range, :step, step), opts)
-    end
-  end
-end

lib/elixir/lib/calendar/time.ex

@@ -1,784 +0,0 @@
-defmodule Time do
-  @moduledoc """
-  A Time struct and functions.
-
-  The Time struct contains the fields hour, minute, second and microseconds.
-  New times can be built with the `new/4` function or using the
-  `~T` (see `Kernel.sigil_T/2`) sigil:
-
-      iex> ~T[23:00:07.001]
-      ~T[23:00:07.001]
-
-  Both `new/4` and sigil return a struct where the time fields can
-  be accessed directly:
-
-      iex> time = ~T[23:00:07.001]
-      iex> time.hour
-      23
-      iex> time.microsecond
-      {1000, 3}
-
-  The functions on this module work with the `Time` struct as well
-  as any struct that contains the same fields as the `Time` struct,
-  such as `NaiveDateTime` and `DateTime`. Such functions expect
-  `t:Calendar.time/0` in their typespecs (instead of `t:t/0`).
-
-  Developers should avoid creating the Time structs directly
-  and instead rely on the functions provided by this module as well
-  as the ones in third-party calendar libraries.
-
-  ## Comparing times
-
-  Comparisons in Elixir using `==/2`, `>/2`, `</2` and similar are structural
-  and based on the `Time` struct fields. For proper comparison between
-  times, use the `compare/2` function.
-  """
-
-  @enforce_keys [:hour, :minute, :second]
-  defstruct [:hour, :minute, :second, microsecond: {0, 0}, calendar: Calendar.ISO]
-
-  @type t :: %__MODULE__{
-          hour: Calendar.hour(),
-          minute: Calendar.minute(),
-          second: Calendar.second(),
-          microsecond: Calendar.microsecond(),
-          calendar: Calendar.calendar()
-        }
-
-  @parts_per_day 86_400_000_000
-  @seconds_per_day 24 * 60 * 60
-
-  @doc """
-  Returns the current time in UTC.
-
-  ## Examples
-
-      iex> time = Time.utc_now()
-      iex> time.hour >= 0
-      true
-
-  """
-  @doc since: "1.4.0"
-  @spec utc_now(Calendar.calendar()) :: t
-  def utc_now(calendar \\ Calendar.ISO) do
-    {:ok, _, time, microsecond} = Calendar.ISO.from_unix(:os.system_time(), :native)
-    {hour, minute, second} = time
-
-    iso_time = %Time{
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: microsecond,
-      calendar: Calendar.ISO
-    }
-
-    convert!(iso_time, calendar)
-  end
-
-  @doc """
-  Builds a new time.
-
-  Expects all values to be integers. Returns `{:ok, time}` if each
-  entry fits its appropriate range, returns `{:error, reason}` otherwise.
-
-  Microseconds can also be given with a precision, which must be an
-  integer between 0 and 6.
-
-  The built-in calendar does not support leap seconds.
-
-  ## Examples
-
-      iex> Time.new(0, 0, 0, 0)
-      {:ok, ~T[00:00:00.000000]}
-      iex> Time.new(23, 59, 59, 999_999)
-      {:ok, ~T[23:59:59.999999]}
-
-      iex> Time.new(24, 59, 59, 999_999)
-      {:error, :invalid_time}
-      iex> Time.new(23, 60, 59, 999_999)
-      {:error, :invalid_time}
-      iex> Time.new(23, 59, 60, 999_999)
-      {:error, :invalid_time}
-      iex> Time.new(23, 59, 59, 1_000_000)
-      {:error, :invalid_time}
-
-      # Invalid precision
-      Time.new(23, 59, 59, {999_999, 10})
-      {:error, :invalid_time}
-
-  """
-  @spec new(
-          Calendar.hour(),
-          Calendar.minute(),
-          Calendar.second(),
-          Calendar.microsecond() | non_neg_integer,
-          Calendar.calendar()
-        ) :: {:ok, t} | {:error, atom}
-  def new(hour, minute, second, microsecond \\ {0, 0}, calendar \\ Calendar.ISO)
-
-  def new(hour, minute, second, microsecond, calendar) when is_integer(microsecond) do
-    new(hour, minute, second, {microsecond, 6}, calendar)
-  end
-
-  def new(hour, minute, second, {microsecond, precision}, calendar)
-      when is_integer(hour) and is_integer(minute) and is_integer(second) and
-             is_integer(microsecond) and is_integer(precision) do
-    case calendar.valid_time?(hour, minute, second, {microsecond, precision}) do
-      true ->
-        time = %Time{
-          hour: hour,
-          minute: minute,
-          second: second,
-          microsecond: {microsecond, precision},
-          calendar: calendar
-        }
-
-        {:ok, time}
-
-      false ->
-        {:error, :invalid_time}
-    end
-  end
-
-  @doc """
-  Builds a new time.
-
-  Expects all values to be integers. Returns `time` if each
-  entry fits its appropriate range, raises if the time is invalid.
-
-  Microseconds can also be given with a precision, which must be an
-  integer between 0 and 6.
-
-  The built-in calendar does not support leap seconds.
-
-  ## Examples
-
-      iex> Time.new!(0, 0, 0, 0)
-      ~T[00:00:00.000000]
-      iex> Time.new!(23, 59, 59, 999_999)
-      ~T[23:59:59.999999]
-      iex> Time.new!(24, 59, 59, 999_999)
-      ** (ArgumentError) cannot build time, reason: :invalid_time
-  """
-  @doc since: "1.11.0"
-  @spec new!(
-          Calendar.hour(),
-          Calendar.minute(),
-          Calendar.second(),
-          Calendar.microsecond() | non_neg_integer,
-          Calendar.calendar()
-        ) :: t
-  def new!(hour, minute, second, microsecond \\ {0, 0}, calendar \\ Calendar.ISO) do
-    case new(hour, minute, second, microsecond, calendar) do
-      {:ok, time} ->
-        time
-
-      {:error, reason} ->
-        raise ArgumentError, "cannot build time, reason: #{inspect(reason)}"
-    end
-  end
-
-  @doc """
-  Converts the given `time` to a string.
-
-  ### Examples
-
-      iex> Time.to_string(~T[23:00:00])
-      "23:00:00"
-      iex> Time.to_string(~T[23:00:00.001])
-      "23:00:00.001"
-      iex> Time.to_string(~T[23:00:00.123456])
-      "23:00:00.123456"
-
-      iex> Time.to_string(~N[2015-01-01 23:00:00.001])
-      "23:00:00.001"
-      iex> Time.to_string(~N[2015-01-01 23:00:00.123456])
-      "23:00:00.123456"
-
-  """
-  @spec to_string(Calendar.time()) :: String.t()
-  def to_string(time)
-
-  def to_string(%{
-        hour: hour,
-        minute: minute,
-        second: second,
-        microsecond: microsecond,
-        calendar: calendar
-      }) do
-    calendar.time_to_string(hour, minute, second, microsecond)
-  end
-
-  @doc """
-  Parses the extended "Local time" format described by
-  [ISO 8601:2019](https://en.wikipedia.org/wiki/ISO_8601).
-
-  Time zone offset may be included in the string but they will be
-  simply discarded as such information is not included in times.
-
-  As specified in the standard, the separator "T" may be omitted if
-  desired as there is no ambiguity within this function.
-
-  ## Examples
-
-      iex> Time.from_iso8601("23:50:07")
-      {:ok, ~T[23:50:07]}
-      iex> Time.from_iso8601("23:50:07Z")
-      {:ok, ~T[23:50:07]}
-      iex> Time.from_iso8601("T23:50:07Z")
-      {:ok, ~T[23:50:07]}
-
-      iex> Time.from_iso8601("23:50:07,0123456")
-      {:ok, ~T[23:50:07.012345]}
-      iex> Time.from_iso8601("23:50:07.0123456")
-      {:ok, ~T[23:50:07.012345]}
-      iex> Time.from_iso8601("23:50:07.123Z")
-      {:ok, ~T[23:50:07.123]}
-
-      iex> Time.from_iso8601("2015:01:23 23-50-07")
-      {:error, :invalid_format}
-      iex> Time.from_iso8601("23:50:07A")
-      {:error, :invalid_format}
-      iex> Time.from_iso8601("23:50:07.")
-      {:error, :invalid_format}
-      iex> Time.from_iso8601("23:50:61")
-      {:error, :invalid_time}
-
-  """
-  @spec from_iso8601(String.t(), Calendar.calendar()) :: {:ok, t} | {:error, atom}
-  def from_iso8601(string, calendar \\ Calendar.ISO) do
-    with {:ok, {hour, minute, second, microsecond}} <- Calendar.ISO.parse_time(string) do
-      convert(
-        %Time{hour: hour, minute: minute, second: second, microsecond: microsecond},
-        calendar
-      )
-    end
-  end
-
-  @doc """
-  Parses the extended "Local time" format described by
-  [ISO 8601:2019](https://en.wikipedia.org/wiki/ISO_8601).
-
-  Raises if the format is invalid.
-
-  ## Examples
-
-      iex> Time.from_iso8601!("23:50:07,123Z")
-      ~T[23:50:07.123]
-      iex> Time.from_iso8601!("23:50:07.123Z")
-      ~T[23:50:07.123]
-      iex> Time.from_iso8601!("2015:01:23 23-50-07")
-      ** (ArgumentError) cannot parse "2015:01:23 23-50-07" as time, reason: :invalid_format
-
-  """
-  @spec from_iso8601!(String.t(), Calendar.calendar()) :: t
-  def from_iso8601!(string, calendar \\ Calendar.ISO) do
-    case from_iso8601(string, calendar) do
-      {:ok, value} ->
-        value
-
-      {:error, reason} ->
-        raise ArgumentError, "cannot parse #{inspect(string)} as time, reason: #{inspect(reason)}"
-    end
-  end
-
-  @doc """
-  Converts the given time to
-  [ISO 8601:2019](https://en.wikipedia.org/wiki/ISO_8601).
-
-  By default, `Time.to_iso8601/2` returns times formatted in the "extended"
-  format, for human readability. It also supports the "basic" format through
-  passing the `:basic` option.
-
-  ### Examples
-
-      iex> Time.to_iso8601(~T[23:00:13])
-      "23:00:13"
-
-      iex> Time.to_iso8601(~T[23:00:13.001])
-      "23:00:13.001"
-
-      iex> Time.to_iso8601(~T[23:00:13.001], :basic)
-      "230013.001"
-
-      iex> Time.to_iso8601(~N[2010-04-17 23:00:13])
-      "23:00:13"
-
-  """
-  @spec to_iso8601(Calendar.time(), :extended | :basic) :: String.t()
-  def to_iso8601(time, format \\ :extended)
-
-  def to_iso8601(%{calendar: Calendar.ISO} = time, format) when format in [:extended, :basic] do
-    %{
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: microsecond
-    } = time
-
-    Calendar.ISO.time_to_string(hour, minute, second, microsecond, format)
-  end
-
-  def to_iso8601(%{calendar: _} = time, format) when format in [:extended, :basic] do
-    time
-    |> convert!(Calendar.ISO)
-    |> to_iso8601(format)
-  end
-
-  @doc """
-  Converts given `time` to an Erlang time tuple.
-
-  WARNING: Loss of precision may occur, as Erlang time tuples
-  only contain hours/minutes/seconds.
-
-  ## Examples
-
-      iex> Time.to_erl(~T[23:30:15.999])
-      {23, 30, 15}
-
-      iex> Time.to_erl(~N[2010-04-17 23:30:15.999])
-      {23, 30, 15}
-
-  """
-  @spec to_erl(Calendar.time()) :: :calendar.time()
-  def to_erl(time) do
-    %{hour: hour, minute: minute, second: second} = convert!(time, Calendar.ISO)
-    {hour, minute, second}
-  end
-
-  @doc """
-  Converts an Erlang time tuple to a `Time` struct.
-
-  ## Examples
-
-      iex> Time.from_erl({23, 30, 15}, {5000, 3})
-      {:ok, ~T[23:30:15.005]}
-      iex> Time.from_erl({24, 30, 15})
-      {:error, :invalid_time}
-
-  """
-  @spec from_erl(:calendar.time(), Calendar.microsecond(), Calendar.calendar()) ::
-          {:ok, t} | {:error, atom}
-  def from_erl(tuple, microsecond \\ {0, 0}, calendar \\ Calendar.ISO)
-
-  def from_erl({hour, minute, second}, microsecond, calendar) do
-    with {:ok, time} <- new(hour, minute, second, microsecond, Calendar.ISO),
-         do: convert(time, calendar)
-  end
-
-  @doc """
-  Converts an Erlang time tuple to a `Time` struct.
-
-  ## Examples
-
-      iex> Time.from_erl!({23, 30, 15})
-      ~T[23:30:15]
-      iex> Time.from_erl!({23, 30, 15}, {5000, 3})
-      ~T[23:30:15.005]
-      iex> Time.from_erl!({24, 30, 15})
-      ** (ArgumentError) cannot convert {24, 30, 15} to time, reason: :invalid_time
-
-  """
-  @spec from_erl!(:calendar.time(), Calendar.microsecond(), Calendar.calendar()) :: t
-  def from_erl!(tuple, microsecond \\ {0, 0}, calendar \\ Calendar.ISO) do
-    case from_erl(tuple, microsecond, calendar) do
-      {:ok, value} ->
-        value
-
-      {:error, reason} ->
-        raise ArgumentError,
-              "cannot convert #{inspect(tuple)} to time, reason: #{inspect(reason)}"
-    end
-  end
-
-  @doc """
-  Converts a number of seconds after midnight to a `Time` struct.
-
-  ## Examples
-
-      iex> Time.from_seconds_after_midnight(10_000)
-      ~T[02:46:40]
-      iex> Time.from_seconds_after_midnight(30_000, {5000, 3})
-      ~T[08:20:00.005]
-      iex> Time.from_seconds_after_midnight(-1)
-      ~T[23:59:59]
-      iex> Time.from_seconds_after_midnight(100_000)
-      ~T[03:46:40]
-
-  """
-  @doc since: "1.11.0"
-  @spec from_seconds_after_midnight(
-          integer(),
-          Calendar.microsecond(),
-          Calendar.calendar()
-        ) :: t
-  def from_seconds_after_midnight(seconds, microsecond \\ {0, 0}, calendar \\ Calendar.ISO)
-      when is_integer(seconds) do
-    seconds_in_day = Integer.mod(seconds, @seconds_per_day)
-
-    {hour, minute, second, {_, _}} =
-      calendar.time_from_day_fraction({seconds_in_day, @seconds_per_day})
-
-    %Time{
-      calendar: calendar,
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: microsecond
-    }
-  end
-
-  @doc """
-  Converts a `Time` struct to a number of seconds after midnight.
-
-  The returned value is a two-element tuple with the number of seconds and microseconds.
-
-  ## Examples
-
-      iex> Time.to_seconds_after_midnight(~T[23:30:15])
-      {84615, 0}
-      iex> Time.to_seconds_after_midnight(~N[2010-04-17 23:30:15.999])
-      {84615, 999000}
-
-  """
-  @doc since: "1.11.0"
-  @spec to_seconds_after_midnight(Calendar.time()) :: {integer(), non_neg_integer()}
-  def to_seconds_after_midnight(%{microsecond: {microsecond, _precision}} = time) do
-    iso_days = {0, to_day_fraction(time)}
-    {Calendar.ISO.iso_days_to_unit(iso_days, :second), microsecond}
-  end
-
-  @doc """
-  Adds the `number` of `unit`s to the given `time`.
-
-  This function accepts the `number` measured according to `Calendar.ISO`.
-  The time is returned in the same calendar as it was given in.
-
-  Note the result value represents the time of day, meaning that it is cyclic,
-  for instance, it will never go over 24 hours for the ISO calendar.
-
-  ## Examples
-
-      iex> Time.add(~T[10:00:00], 27000)
-      ~T[17:30:00.000000]
-      iex> Time.add(~T[11:00:00.005], 2400)
-      ~T[11:40:00.005000]
-      iex> Time.add(~T[00:00:00], 86_399_999, :millisecond)
-      ~T[23:59:59.999000]
-      iex> Time.add(~T[17:10:05], 86400)
-      ~T[17:10:05.000000]
-      iex> Time.add(~T[23:00:00], -60)
-      ~T[22:59:00.000000]
-
-  """
-  @doc since: "1.6.0"
-  @spec add(Calendar.time(), integer, System.time_unit()) :: t
-  def add(%{calendar: calendar} = time, number, unit \\ :second) when is_integer(number) do
-    number = System.convert_time_unit(number, unit, :microsecond)
-    total = time_to_microseconds(time) + number
-    parts = Integer.mod(total, @parts_per_day)
-    {hour, minute, second, microsecond} = calendar.time_from_day_fraction({parts, @parts_per_day})
-
-    %Time{
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: microsecond,
-      calendar: calendar
-    }
-  end
-
-  defp time_to_microseconds(%{
-         calendar: Calendar.ISO,
-         hour: 0,
-         minute: 0,
-         second: 0,
-         microsecond: {0, _}
-       }) do
-    0
-  end
-
-  defp time_to_microseconds(time) do
-    iso_days = {0, to_day_fraction(time)}
-    Calendar.ISO.iso_days_to_unit(iso_days, :microsecond)
-  end
-
-  @doc """
-  Compares two time structs.
-
-  Returns `:gt` if first time is later than the second
-  and `:lt` for vice versa. If the two times are equal
-  `:eq` is returned.
-
-  ## Examples
-
-      iex> Time.compare(~T[16:04:16], ~T[16:04:28])
-      :lt
-      iex> Time.compare(~T[16:04:16], ~T[16:04:16])
-      :eq
-      iex> Time.compare(~T[16:04:16.01], ~T[16:04:16.001])
-      :gt
-
-  This function can also be used to compare across more
-  complex calendar types by considering only the time fields:
-
-      iex> Time.compare(~N[1900-01-01 16:04:16], ~N[2015-01-01 16:04:16])
-      :eq
-      iex> Time.compare(~N[2015-01-01 16:04:16], ~N[2015-01-01 16:04:28])
-      :lt
-      iex> Time.compare(~N[2015-01-01 16:04:16.01], ~N[2000-01-01 16:04:16.001])
-      :gt
-
-  """
-  @doc since: "1.4.0"
-  @spec compare(Calendar.time(), Calendar.time()) :: :lt | :eq | :gt
-  def compare(%{calendar: calendar} = time1, %{calendar: calendar} = time2) do
-    %{hour: hour1, minute: minute1, second: second1, microsecond: {microsecond1, _}} = time1
-    %{hour: hour2, minute: minute2, second: second2, microsecond: {microsecond2, _}} = time2
-
-    case {{hour1, minute1, second1, microsecond1}, {hour2, minute2, second2, microsecond2}} do
-      {first, second} when first > second -> :gt
-      {first, second} when first < second -> :lt
-      _ -> :eq
-    end
-  end
-
-  def compare(time1, time2) do
-    {parts1, ppd1} = to_day_fraction(time1)
-    {parts2, ppd2} = to_day_fraction(time2)
-
-    case {parts1 * ppd2, parts2 * ppd1} do
-      {first, second} when first > second -> :gt
-      {first, second} when first < second -> :lt
-      _ -> :eq
-    end
-  end
-
-  @doc """
-  Converts given `time` to a different calendar.
-
-  Returns `{:ok, time}` if the conversion was successful,
-  or `{:error, reason}` if it was not, for some reason.
-
-  ## Examples
-
-  Imagine someone implements `Calendar.Holocene`, a calendar based on the
-  Gregorian calendar that adds exactly 10,000 years to the current Gregorian
-  year:
-
-      iex> Time.convert(~T[13:30:15], Calendar.Holocene)
-      {:ok, %Time{calendar: Calendar.Holocene, hour: 13, minute: 30, second: 15, microsecond: {0, 0}}}
-
-  """
-  @doc since: "1.5.0"
-  @spec convert(Calendar.time(), Calendar.calendar()) :: {:ok, t} | {:error, atom}
-
-  # Keep it multiline for proper function clause errors.
-  def convert(
-        %{
-          calendar: calendar,
-          hour: hour,
-          minute: minute,
-          second: second,
-          microsecond: microsecond
-        },
-        calendar
-      ) do
-    time = %Time{
-      calendar: calendar,
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: microsecond
-    }
-
-    {:ok, time}
-  end
-
-  def convert(%{microsecond: {_, precision}} = time, calendar) do
-    {hour, minute, second, {microsecond, _}} =
-      time
-      |> to_day_fraction()
-      |> calendar.time_from_day_fraction()
-
-    time = %Time{
-      calendar: calendar,
-      hour: hour,
-      minute: minute,
-      second: second,
-      microsecond: {microsecond, precision}
-    }
-
-    {:ok, time}
-  end
-
-  @doc """
-  Similar to `Time.convert/2`, but raises an `ArgumentError`
-  if the conversion between the two calendars is not possible.
-
-  ## Examples
-
-  Imagine someone implements `Calendar.Holocene`, a calendar based on the
-  Gregorian calendar that adds exactly 10,000 years to the current Gregorian
-  year:
-
-      iex> Time.convert!(~T[13:30:15], Calendar.Holocene)
-      %Time{calendar: Calendar.Holocene, hour: 13, minute: 30, second: 15, microsecond: {0, 0}}
-
-  """
-  @doc since: "1.5.0"
-  @spec convert!(Calendar.time(), Calendar.calendar()) :: t
-  def convert!(time, calendar) do
-    case convert(time, calendar) do
-      {:ok, value} ->
-        value
-
-      {:error, reason} ->
-        raise ArgumentError,
-              "cannot convert #{inspect(time)} to target calendar #{inspect(calendar)}, " <>
-                "reason: #{inspect(reason)}"
-    end
-  end
-
-  @doc """
-  Returns the difference between two times, considering only the hour, minute,
-  second and microsecond.
-
-  As with the `compare/2` function both `Time` structs and other structures
-  containing time can be used. If for instance a `NaiveDateTime` or `DateTime`
-  is passed, only the hour, minute, second, and microsecond is considered. Any
-  additional information about a date or time zone is ignored when calculating
-  the difference.
-
-  The answer can be returned in any `unit` available from
-  `t:System.time_unit/0`. If the first time value is earlier than
-  the second, a negative number is returned.
-
-  This function returns the difference in seconds where seconds
-  are measured according to `Calendar.ISO`.
-
-  ## Examples
-
-      iex> Time.diff(~T[00:29:12], ~T[00:29:10])
-      2
-
-      # When passing a `NaiveDateTime` the date part is ignored.
-      iex> Time.diff(~N[2017-01-01 00:29:12], ~T[00:29:10])
-      2
-
-      # Two `NaiveDateTime` structs could have big differences in the date
-      # but only the time part is considered.
-      iex> Time.diff(~N[2017-01-01 00:29:12], ~N[1900-02-03 00:29:10])
-      2
-
-      iex> Time.diff(~T[00:29:12], ~T[00:29:10], :microsecond)
-      2_000_000
-      iex> Time.diff(~T[00:29:10], ~T[00:29:12], :microsecond)
-      -2_000_000
-
-  """
-  @doc since: "1.5.0"
-  @spec diff(Calendar.time(), Calendar.time(), System.time_unit()) :: integer
-  def diff(time1, time2, unit \\ :second)
-
-  def diff(
-        %{
-          calendar: Calendar.ISO,
-          hour: hour1,
-          minute: minute1,
-          second: second1,
-          microsecond: {microsecond1, @parts_per_day}
-        },
-        %{
-          calendar: Calendar.ISO,
-          hour: hour2,
-          minute: minute2,
-          second: second2,
-          microsecond: {microsecond2, @parts_per_day}
-        },
-        unit
-      ) do
-    total =
-      (hour1 - hour2) * 3_600_000_000 + (minute1 - minute2) * 60_000_000 +
-        (second1 - second2) * 1_000_000 + (microsecond1 - microsecond2)
-
-    System.convert_time_unit(total, :microsecond, unit)
-  end
-
-  def diff(time1, time2, unit) do
-    fraction1 = to_day_fraction(time1)
-    fraction2 = to_day_fraction(time2)
-
-    Calendar.ISO.iso_days_to_unit({0, fraction1}, unit) -
-      Calendar.ISO.iso_days_to_unit({0, fraction2}, unit)
-  end
-
-  @doc """
-  Returns the given time with the microsecond field truncated to the given
-  precision (`:microsecond`, `millisecond` or `:second`).
-
-  The given time is returned unchanged if it already has lower precision than
-  the given precision.
-
-  ## Examples
-
-      iex> Time.truncate(~T[01:01:01.123456], :microsecond)
-      ~T[01:01:01.123456]
-
-      iex> Time.truncate(~T[01:01:01.123456], :millisecond)
-      ~T[01:01:01.123]
-
-      iex> Time.truncate(~T[01:01:01.123456], :second)
-      ~T[01:01:01]
-
-  """
-  @doc since: "1.6.0"
-  @spec truncate(t(), :microsecond | :millisecond | :second) :: t()
-  def truncate(%Time{microsecond: microsecond} = time, precision) do
-    %{time | microsecond: Calendar.truncate(microsecond, precision)}
-  end
-
-  ## Helpers
-
-  defp to_day_fraction(%{
-         hour: hour,
-         minute: minute,
-         second: second,
-         microsecond: {_, _} = microsecond,
-         calendar: calendar
-       }) do
-    calendar.time_to_day_fraction(hour, minute, second, microsecond)
-  end
-
-  defimpl String.Chars do
-    def to_string(time) do
-      %{
-        hour: hour,
-        minute: minute,
-        second: second,
-        microsecond: microsecond,
-        calendar: calendar
-      } = time
-
-      calendar.time_to_string(hour, minute, second, microsecond)
-    end
-  end
-
-  defimpl Inspect do
-    def inspect(time, _) do
-      %{
-        hour: hour,
-        minute: minute,
-        second: second,
-        microsecond: microsecond,
-        calendar: calendar
-      } = time
-
-      "~T[" <>
-        calendar.time_to_string(hour, minute, second, microsecond) <> suffix(calendar) <> "]"
-    end
-
-    defp suffix(Calendar.ISO), do: ""
-    defp suffix(calendar), do: " " <> inspect(calendar)
-  end
-end

lib/elixir/lib/calendar/time_zone_database.ex

@@ -1,96 +0,0 @@
-defmodule Calendar.TimeZoneDatabase do
-  @moduledoc """
-  This module defines a behaviour for providing time zone data.
-
-  IANA provides time zone data that includes data about different
-  UTC offsets and standard offsets for time zones.
-  """
-
-  @typedoc """
-  A period where a certain combination of UTC offset, standard offset and zone
-  abbreviation is in effect.
-
-  For instance one period could be the summer of 2018 in "Europe/London" where summer time /
-  daylight saving time is in effect and lasts from spring to autumn. At autumn the `std_offset`
-  changes along with the `zone_abbr` so a different period is needed during winter.
-  """
-  @type time_zone_period :: %{
-          optional(any) => any,
-          utc_offset: Calendar.utc_offset(),
-          std_offset: Calendar.std_offset(),
-          zone_abbr: Calendar.zone_abbr()
-        }
-
-  @typedoc """
-  Limit for when a certain time zone period begins or ends.
-
-  A beginning is inclusive. An ending is exclusive. Eg. if a period is from
-  2015-03-29 01:00:00 and until 2015-10-25 01:00:00, the period includes and
-  begins from the beginning of 2015-03-29 01:00:00 and lasts until just before
-  2015-10-25 01:00:00.
-
-  A beginning or end for certain periods are infinite. For instance the latest
-  period for time zones without DST or plans to change. However for the purpose
-  of this behaviour they are only used for gaps in wall time where the needed
-  period limits are at a certain time.
-  """
-  @type time_zone_period_limit :: Calendar.naive_datetime()
-
-  @doc """
-  Time zone period for a point in time in UTC for a specific time zone.
-
-  Takes a time zone name and a point in time for UTC and returns a
-  `time_zone_period` for that point in time.
-  """
-  @doc since: "1.8.0"
-  @callback time_zone_period_from_utc_iso_days(Calendar.iso_days(), Calendar.time_zone()) ::
-              {:ok, time_zone_period}
-              | {:error, :time_zone_not_found | :utc_only_time_zone_database}
-
-  @doc """
-  Possible time zone periods for a certain time zone and wall clock date and time.
-
-  When the provided `datetime` is ambiguous a tuple with `:ambiguous` and two possible
-  periods. The periods in the list are sorted with the first element being the one that begins first.
-
-  When the provided `datetime` is in a gap - for instance during the "spring forward" when going
-  from winter time to summer time, a tuple with `:gap` and two periods with limits are returned
-  in a nested tuple. The first nested two-tuple is the period before the gap and a naive datetime
-  with a limit for when the period ends (wall time). The second nested two-tuple is the period
-  just after the gap and a datetime (wall time) for when the period begins just after the gap.
-
-  If there is only a single possible period for the provided `datetime`, then a tuple with `:ok`
-  and the `time_zone_period` is returned.
-  """
-  @doc since: "1.8.0"
-  @callback time_zone_periods_from_wall_datetime(Calendar.naive_datetime(), Calendar.time_zone()) ::
-              {:ok, time_zone_period}
-              | {:ambiguous, time_zone_period, time_zone_period}
-              | {:gap, {time_zone_period, time_zone_period_limit},
-                 {time_zone_period, time_zone_period_limit}}
-              | {:error, :time_zone_not_found | :utc_only_time_zone_database}
-end
-
-defmodule Calendar.UTCOnlyTimeZoneDatabase do
-  @moduledoc """
-  Built-in time zone database that works only in Etc/UTC.
-
-  For all other time zones, it returns `{:error, :utc_only_time_zone_database}`.
-  """
-
-  @behaviour Calendar.TimeZoneDatabase
-
-  @impl true
-  def time_zone_period_from_utc_iso_days(_, "Etc/UTC"),
-    do: {:ok, %{std_offset: 0, utc_offset: 0, zone_abbr: "UTC"}}
-
-  def time_zone_period_from_utc_iso_days(_, _),
-    do: {:error, :utc_only_time_zone_database}
-
-  @impl true
-  def time_zone_periods_from_wall_datetime(_, "Etc/UTC"),
-    do: {:ok, %{std_offset: 0, utc_offset: 0, zone_abbr: "UTC"}}
-
-  def time_zone_periods_from_wall_datetime(_, _),
-    do: {:error, :utc_only_time_zone_database}
-end

lib/elixir/lib/code/fragment.ex

@@ -1,841 +0,0 @@
-defmodule Code.Fragment do
-  @moduledoc """
-  This module provides conveniences for analyzing fragments of
-  textual code and extract available information whenever possible.
-
-  Most of the functions in this module provide a best-effort
-  and may not be accurate under all circumstances. Read each
-  documentation for more information.
-
-  This module should be considered experimental.
-  """
-
-  @type position :: {line :: pos_integer(), column :: pos_integer()}
-
-  @doc """
-  Receives a string and returns the cursor context.
-
-  This function receives a string with an Elixir code fragment,
-  representing a cursor position, and based on the string, it
-  provides contextual information about said position. The
-  return of this function can then be used to provide tips,
-  suggestions, and autocompletion functionality.
-
-  This function provides a best-effort detection and may not be
-  accurate under all circumstances. See the "Limitations"
-  section below.
-
-  Consider adding a catch-all clause when handling the return
-  type of this function as new cursor information may be added
-  in future releases.
-
-  ## Examples
-
-      iex> Code.Fragment.cursor_context("")
-      :expr
-
-      iex> Code.Fragment.cursor_context("hello_wor")
-      {:local_or_var, 'hello_wor'}
-
-  ## Return values
-
-    * `{:alias, charlist}` - the context is an alias, potentially
-      a nested one, such as `Hello.Wor` or `HelloWor`
-
-    * `{:dot, inside_dot, charlist}` - the context is a dot
-      where `inside_dot` is either a `{:var, charlist}`, `{:alias, charlist}`,
-      `{:module_attribute, charlist}`, `{:unquoted_atom, charlist}` or a `dot`
-      itself. If a var is given, this may either be a remote call or a map
-      field access. Examples are `Hello.wor`, `:hello.wor`, `hello.wor`,
-      `Hello.nested.wor`, `hello.nested.wor`, and `@hello.world`
-
-    * `{:dot_arity, inside_dot, charlist}` - the context is a dot arity
-      where `inside_dot` is either a `{:var, charlist}`, `{:alias, charlist}`,
-      `{:module_attribute, charlist}`, `{:unquoted_atom, charlist}` or a `dot`
-      itself. If a var is given, it must be a remote arity. Examples are
-      `Hello.world/`, `:hello.world/`, `hello.world/2`, and `@hello.world/2`
-
-    * `{:dot_call, inside_dot, charlist}` - the context is a dot
-      call. This means parentheses or space have been added after the expression.
-      where `inside_dot` is either a `{:var, charlist}`, `{:alias, charlist}`,
-      `{:module_attribute, charlist}`, `{:unquoted_atom, charlist}` or a `dot`
-      itself. If a var is given, it must be a remote call. Examples are
-      `Hello.world(`, `:hello.world(`, `Hello.world `, `hello.world(`, `hello.world `,
-      and `@hello.world(`
-
-    * `:expr` - may be any expression. Autocompletion may suggest an alias,
-      local or var
-
-    * `{:local_or_var, charlist}` - the context is a variable or a local
-      (import or local) call, such as `hello_wor`
-
-    * `{:local_arity, charlist}` - the context is a local (import or local)
-      arity, such as `hello_world/`
-
-    * `{:local_call, charlist}` - the context is a local (import or local)
-      call, such as `hello_world(` and `hello_world `
-
-    * `{:module_attribute, charlist}` - the context is a module attribute,
-      such as `@hello_wor`
-
-    * `{:operator, charlist}` - the context is an operator, such as `+` or
-      `==`. Note textual operators, such as `when` do not appear as operators
-      but rather as `:local_or_var`. `@` is never an `:operator` and always a
-      `:module_attribute`
-
-    * `{:operator_arity, charlist}` - the context is an operator arity, which
-      is an operator followed by /, such as `+/`, `not/` or `when/`
-
-    * `{:operator_call, charlist}` - the context is an operator call, which is
-      an operator followed by space, such as `left + `, `not ` or `x when `
-
-    * `:none` - no context possible
-
-    * `{:sigil, charlist}` - the context is a sigil. It may be either the beginning
-      of a sigil, such as `~` or `~s`, or an operator starting with `~`, such as
-      `~>` and `~>>`
-
-    * `{:struct, charlist}` - the context is a struct, such as `%`, `%UR` or `%URI`
-
-    * `{:unquoted_atom, charlist}` - the context is an unquoted atom. This
-      can be any atom or an atom representing a module
-
-  ## Limitations
-
-  The current algorithm only considers the last line of the input. This means
-  it will also show suggestions inside strings, heredocs, etc, which is
-  intentional as it helps with doctests, references, and more.
-  """
-  @doc since: "1.13.0"
-  @spec cursor_context(List.Chars.t(), keyword()) ::
-          {:alias, charlist}
-          | {:dot, inside_dot, charlist}
-          | {:dot_arity, inside_dot, charlist}
-          | {:dot_call, inside_dot, charlist}
-          | :expr
-          | {:local_or_var, charlist}
-          | {:local_arity, charlist}
-          | {:local_call, charlist}
-          | {:module_attribute, charlist}
-          | {:operator, charlist}
-          | {:operator_arity, charlist}
-          | {:operator_call, charlist}
-          | :none
-          | {:sigil, charlist}
-          | {:struct, charlist}
-          | {:unquoted_atom, charlist}
-        when inside_dot:
-               {:alias, charlist}
-               | {:dot, inside_dot, charlist}
-               | {:module_attribute, charlist}
-               | {:unquoted_atom, charlist}
-               | {:var, charlist}
-  def cursor_context(fragment, opts \\ [])
-
-  def cursor_context(binary, opts) when is_binary(binary) and is_list(opts) do
-    binary =
-      case :binary.matches(binary, "\n") do
-        [] ->
-          binary
-
-        matches ->
-          {position, _} = List.last(matches)
-          binary_part(binary, position + 1, byte_size(binary) - position - 1)
-      end
-
-    binary
-    |> String.to_charlist()
-    |> :lists.reverse()
-    |> codepoint_cursor_context(opts)
-    |> elem(0)
-  end
-
-  def cursor_context(charlist, opts) when is_list(charlist) and is_list(opts) do
-    charlist =
-      case charlist |> Enum.chunk_by(&(&1 == ?\n)) |> List.last([]) do
-        [?\n | _] -> []
-        rest -> rest
-      end
-
-    charlist
-    |> :lists.reverse()
-    |> codepoint_cursor_context(opts)
-    |> elem(0)
-  end
-
-  def cursor_context(other, opts) when is_list(opts) do
-    cursor_context(to_charlist(other), opts)
-  end
-
-  @operators '\\<>+-*/:=|&~^%!'
-  @starter_punctuation ',([{;'
-  @non_starter_punctuation ')]}"\'.$'
-  @space '\t\s'
-  @trailing_identifier '?!'
-  @tilde_op_prefix '<=~'
-
-  @non_identifier @trailing_identifier ++
-                    @operators ++ @starter_punctuation ++ @non_starter_punctuation ++ @space
-
-  @textual_operators ~w(when not and or in)c
-  @incomplete_operators ~w(^^ ~~ ~)c
-
-  defp codepoint_cursor_context(reverse, _opts) do
-    {stripped, spaces} = strip_spaces(reverse, 0)
-
-    case stripped do
-      # It is empty
-      [] -> {:expr, 0}
-      # Structs
-      [?%, ?:, ?: | _] -> {{:struct, ''}, 1}
-      [?%, ?: | _] -> {{:unquoted_atom, '%'}, 2}
-      [?% | _] -> {{:struct, ''}, 1}
-      # Token/AST only operators
-      [?>, ?= | rest] when rest == [] or hd(rest) != ?: -> {:expr, 0}
-      [?>, ?- | rest] when rest == [] or hd(rest) != ?: -> {:expr, 0}
-      # Two-digit containers
-      [?<, ?< | rest] when rest == [] or hd(rest) != ?< -> {:expr, 0}
-      # Ambiguity around :
-      [?: | rest] when rest == [] or hd(rest) != ?: -> unquoted_atom_or_expr(spaces)
-      # Dots
-      [?.] -> {:none, 0}
-      [?. | rest] when hd(rest) not in '.:' -> dot(rest, spaces + 1, '')
-      # It is a local or remote call with parens
-      [?( | rest] -> call_to_cursor_context(strip_spaces(rest, spaces + 1))
-      # A local arity definition
-      [?/ | rest] -> arity_to_cursor_context(strip_spaces(rest, spaces + 1))
-      # Starting a new expression
-      [h | _] when h in @starter_punctuation -> {:expr, 0}
-      # It is a local or remote call without parens
-      rest when spaces > 0 -> call_to_cursor_context({rest, spaces})
-      # It is an identifier
-      _ -> identifier_to_cursor_context(reverse, 0, false)
-    end
-  end
-
-  defp strip_spaces([h | rest], count) when h in @space, do: strip_spaces(rest, count + 1)
-  defp strip_spaces(rest, count), do: {rest, count}
-
-  defp unquoted_atom_or_expr(0), do: {{:unquoted_atom, ''}, 1}
-  defp unquoted_atom_or_expr(_), do: {:expr, 0}
-
-  defp arity_to_cursor_context({reverse, spaces}) do
-    case identifier_to_cursor_context(reverse, spaces, true) do
-      {{:local_or_var, acc}, count} -> {{:local_arity, acc}, count}
-      {{:dot, base, acc}, count} -> {{:dot_arity, base, acc}, count}
-      {{:operator, acc}, count} -> {{:operator_arity, acc}, count}
-      {_, _} -> {:none, 0}
-    end
-  end
-
-  defp call_to_cursor_context({reverse, spaces}) do
-    case identifier_to_cursor_context(reverse, spaces, true) do
-      {{:local_or_var, acc}, count} -> {{:local_call, acc}, count}
-      {{:dot, base, acc}, count} -> {{:dot_call, base, acc}, count}
-      {{:operator, acc}, count} -> {{:operator_call, acc}, count}
-      {_, _} -> {:none, 0}
-    end
-  end
-
-  defp identifier_to_cursor_context([?., ?., ?: | _], n, _), do: {{:unquoted_atom, '..'}, n + 3}
-  defp identifier_to_cursor_context([?., ?., ?. | _], n, _), do: {{:local_or_var, '...'}, n + 3}
-  defp identifier_to_cursor_context([?., ?: | _], n, _), do: {{:unquoted_atom, '.'}, n + 2}
-  defp identifier_to_cursor_context([?., ?. | _], n, _), do: {{:operator, '..'}, n + 2}
-
-  defp identifier_to_cursor_context(reverse, count, call_op?) do
-    case identifier(reverse, count) do
-      :none ->
-        {:none, 0}
-
-      :operator ->
-        operator(reverse, count, [], call_op?)
-
-      {:module_attribute, acc, count} ->
-        {{:module_attribute, acc}, count}
-
-      {:sigil, acc, count} ->
-        {{:sigil, acc}, count}
-
-      {:unquoted_atom, acc, count} ->
-        {{:unquoted_atom, acc}, count}
-
-      {:alias, rest, acc, count} ->
-        case strip_spaces(rest, count) do
-          {'.' ++ rest, count} when rest == [] or hd(rest) != ?. ->
-            nested_alias(rest, count + 1, acc)
-
-          {'%' ++ _, count} ->
-            {{:struct, acc}, count + 1}
-
-          _ ->
-            {{:alias, acc}, count}
-        end
-
-      {:identifier, _, acc, count} when call_op? and acc in @textual_operators ->
-        {{:operator, acc}, count}
-
-      {:identifier, rest, acc, count} ->
-        case strip_spaces(rest, count) do
-          {'.' ++ rest, count} when rest == [] or hd(rest) != ?. ->
-            dot(rest, count + 1, acc)
-
-          _ ->
-            {{:local_or_var, acc}, count}
-        end
-    end
-  end
-
-  defp identifier([?? | rest], count), do: check_identifier(rest, count + 1, [??])
-  defp identifier([?! | rest], count), do: check_identifier(rest, count + 1, [?!])
-  defp identifier(rest, count), do: check_identifier(rest, count, [])
-
-  defp check_identifier([h | t], count, acc) when h not in @non_identifier,
-    do: rest_identifier(t, count + 1, [h | acc])
-
-  defp check_identifier(_, _, _), do: :operator
-
-  defp rest_identifier([h | rest], count, acc) when h not in @non_identifier do
-    rest_identifier(rest, count + 1, [h | acc])
-  end
-
-  defp rest_identifier(rest, count, [?@ | acc]) do
-    case tokenize_identifier(rest, count, acc) do
-      {:identifier, _rest, acc, count} -> {:module_attribute, acc, count}
-      :none when acc == [] -> {:module_attribute, '', count}
-      _ -> :none
-    end
-  end
-
-  defp rest_identifier([?~ | rest], count, [letter])
-       when (letter in ?A..?Z or letter in ?a..?z) and
-              (rest == [] or hd(rest) not in @tilde_op_prefix) do
-    {:sigil, [letter], count + 1}
-  end
-
-  defp rest_identifier([?: | rest], count, acc) when rest == [] or hd(rest) != ?: do
-    case String.Tokenizer.tokenize(acc) do
-      {_, _, [], _, _, _} -> {:unquoted_atom, acc, count + 1}
-      _ -> :none
-    end
-  end
-
-  defp rest_identifier([?? | _], _count, _acc) do
-    :none
-  end
-
-  defp rest_identifier(rest, count, acc) do
-    tokenize_identifier(rest, count, acc)
-  end
-
-  defp tokenize_identifier(rest, count, acc) do
-    case String.Tokenizer.tokenize(acc) do
-      # Not actually an atom cause rest is not a :
-      {:atom, _, _, _, _, _} ->
-        :none
-
-      # Aliases must be ascii only
-      {:alias, _, _, _, false, _} ->
-        :none
-
-      {kind, _, [], _, _, extra} ->
-        if ?@ in extra do
-          :none
-        else
-          {kind, rest, acc, count}
-        end
-
-      _ ->
-        :none
-    end
-  end
-
-  defp nested_alias(rest, count, acc) do
-    {rest, count} = strip_spaces(rest, count)
-
-    case identifier_to_cursor_context(rest, count, true) do
-      {{:struct, prev}, count} -> {{:struct, prev ++ '.' ++ acc}, count}
-      {{:alias, prev}, count} -> {{:alias, prev ++ '.' ++ acc}, count}
-      _ -> {:none, 0}
-    end
-  end
-
-  defp dot(rest, count, acc) do
-    {rest, count} = strip_spaces(rest, count)
-
-    case identifier_to_cursor_context(rest, count, true) do
-      {{:local_or_var, var}, count} -> {{:dot, {:var, var}, acc}, count}
-      {{:unquoted_atom, _} = prev, count} -> {{:dot, prev, acc}, count}
-      {{:alias, _} = prev, count} -> {{:dot, prev, acc}, count}
-      {{:dot, _, _} = prev, count} -> {{:dot, prev, acc}, count}
-      {{:module_attribute, _} = prev, count} -> {{:dot, prev, acc}, count}
-      {{:struct, acc}, count} -> {{:struct, acc ++ '.'}, count}
-      {_, _} -> {:none, 0}
-    end
-  end
-
-  defp operator([h | rest], count, acc, call_op?) when h in @operators do
-    operator(rest, count + 1, [h | acc], call_op?)
-  end
-
-  defp operator(rest, count, acc, call_op?) when acc in @incomplete_operators do
-    {rest, dot_count} = strip_spaces(rest, count)
-
-    cond do
-      call_op? ->
-        {:none, 0}
-
-      match?([?. | rest] when rest == [] or hd(rest) != ?., rest) ->
-        dot(tl(rest), dot_count + 1, acc)
-
-      acc == '~' ->
-        {{:sigil, ''}, count}
-
-      true ->
-        {{:operator, acc}, count}
-    end
-  end
-
-  # If we are opening a sigil, ignore the operator.
-  defp operator([letter, ?~ | rest], _count, [op], _call_op?)
-       when op in '<|/' and (letter in ?A..?Z or letter in ?a..?z) and
-              (rest == [] or hd(rest) not in @tilde_op_prefix) do
-    {:none, 0}
-  end
-
-  defp operator(rest, count, acc, _call_op?) do
-    case :elixir_tokenizer.tokenize(acc, 1, 1, []) do
-      {:ok, _, _, _, [{:atom, _, _}]} ->
-        {{:unquoted_atom, tl(acc)}, count}
-
-      {:ok, _, _, _, [{_, _, op}]} ->
-        {rest, dot_count} = strip_spaces(rest, count)
-
-        cond do
-          Code.Identifier.unary_op(op) == :error and Code.Identifier.binary_op(op) == :error ->
-            :none
-
-          match?([?. | rest] when rest == [] or hd(rest) != ?., rest) ->
-            dot(tl(rest), dot_count + 1, acc)
-
-          true ->
-            {{:operator, acc}, count}
-        end
-
-      _ ->
-        {:none, 0}
-    end
-  end
-
-  @doc """
-  Receives a string and returns the surround context.
-
-  This function receives a string with an Elixir code fragment
-  and a `position`. It returns a map containing the beginning
-  and ending of the identifier alongside its context, or `:none`
-  if there is nothing with a known context.
-
-  The difference between `cursor_context/2` and `surround_context/3`
-  is that the former assumes the expression in the code fragment
-  is incomplete. For example, `do` in `cursor_context/2` may be
-  a keyword or a variable or a local call, while `surround_context/3`
-  assumes the expression in the code fragment is complete, therefore
-  `do` would always be a keyword.
-
-  The `position` contains both the `line` and `column`, both starting
-  with the index of 1. The column must precede the surrounding expression.
-  For example, the expression `foo`, will return something for the columns
-  1, 2, and 3, but not 4:
-
-      foo
-      ^ column 1
-
-      foo
-       ^ column 2
-
-      foo
-        ^ column 3
-
-      foo
-         ^ column 4
-
-  The returned map contains the column the expression starts and the
-  first column after the expression ends.
-
-  Similar to `cursor_context/2`, this function also provides a best-effort
-  detection and may not be accurate under all circumstances. See the
-  "Return values" and "Limitations" section under `cursor_context/2` for
-  more information.
-
-  ## Examples
-
-      iex> Code.Fragment.surround_context("foo", {1, 1})
-      %{begin: {1, 1}, context: {:local_or_var, 'foo'}, end: {1, 4}}
-
-  ## Differences to `cursor_context/2`
-
-  Because `surround_context/3` deals with complete code, it has some
-  difference to `cursor_context/2`:
-
-    * `dot_call`/`dot_arity` and `operator_call`/`operator_arity`
-      are collapsed into `dot` and `operator` contexts respectively
-      as there aren't any meaningful distinctions between them
-
-    * On the other hand, this function still makes a distinction between
-      `local_call`/`local_arity` and `local_or_var`, since the latter can
-      be a local or variable
-
-    * `@` when not followed by any identifier is returned as `{:operator, '@'}`
-      (in contrast to `{:module_attribute, ''}` in `cursor_context/2`
-
-    * This function never returns empty sigils `{:sigil, ''}` or empty structs
-      `{:struct, ''}` as context
-  """
-  @doc since: "1.13.0"
-  @spec surround_context(List.Chars.t(), position(), keyword()) ::
-          %{begin: position, end: position, context: context} | :none
-        when context:
-               {:alias, charlist}
-               | {:dot, inside_dot, charlist}
-               | {:local_or_var, charlist}
-               | {:local_arity, charlist}
-               | {:local_call, charlist}
-               | {:module_attribute, charlist}
-               | {:operator, charlist}
-               | {:unquoted_atom, charlist},
-             inside_dot:
-               {:alias, charlist}
-               | {:dot, inside_dot, charlist}
-               | {:module_attribute, charlist}
-               | {:unquoted_atom, charlist}
-               | {:var, charlist}
-  def surround_context(fragment, position, options \\ [])
-
-  def surround_context(binary, {line, column}, opts) when is_binary(binary) do
-    binary
-    |> String.split("\n")
-    |> Enum.at(line - 1, '')
-    |> String.to_charlist()
-    |> position_surround_context(line, column, opts)
-  end
-
-  def surround_context(charlist, {line, column}, opts) when is_list(charlist) do
-    charlist
-    |> :string.split('\n', :all)
-    |> Enum.at(line - 1, '')
-    |> position_surround_context(line, column, opts)
-  end
-
-  def surround_context(other, {_, _} = position, opts) do
-    surround_context(to_charlist(other), position, opts)
-  end
-
-  defp position_surround_context(charlist, line, column, opts)
-       when is_integer(line) and line >= 1 and is_integer(column) and column >= 1 do
-    {reversed_pre, post} = string_reverse_at(charlist, column - 1, [])
-    {reversed_pre, post} = adjust_position(reversed_pre, post)
-
-    case take_identifier(post, []) do
-      {_, [], _} ->
-        maybe_operator(reversed_pre, post, line, opts)
-
-      {:identifier, reversed_post, rest} ->
-        {rest, _} = strip_spaces(rest, 0)
-        reversed = reversed_post ++ reversed_pre
-
-        case codepoint_cursor_context(reversed, opts) do
-          {{:struct, acc}, offset} ->
-            build_surround({:struct, acc}, reversed, line, offset)
-
-          {{:alias, acc}, offset} ->
-            build_surround({:alias, acc}, reversed, line, offset)
-
-          {{:dot, _, [_ | _]} = dot, offset} ->
-            build_surround(dot, reversed, line, offset)
-
-          {{:local_or_var, acc}, offset} when hd(rest) == ?( ->
-            build_surround({:local_call, acc}, reversed, line, offset)
-
-          {{:local_or_var, acc}, offset} when hd(rest) == ?/ ->
-            build_surround({:local_arity, acc}, reversed, line, offset)
-
-          {{:local_or_var, acc}, offset} when acc in @textual_operators ->
-            build_surround({:operator, acc}, reversed, line, offset)
-
-          {{:local_or_var, acc}, offset} when acc not in ~w(do end after else catch rescue)c ->
-            build_surround({:local_or_var, acc}, reversed, line, offset)
-
-          {{:module_attribute, ''}, offset} ->
-            build_surround({:operator, '@'}, reversed, line, offset)
-
-          {{:module_attribute, acc}, offset} ->
-            build_surround({:module_attribute, acc}, reversed, line, offset)
-
-          {{:sigil, acc}, offset} ->
-            build_surround({:sigil, acc}, reversed, line, offset)
-
-          {{:unquoted_atom, acc}, offset} ->
-            build_surround({:unquoted_atom, acc}, reversed, line, offset)
-
-          _ ->
-            maybe_operator(reversed_pre, post, line, opts)
-        end
-
-      {:alias, reversed_post, _rest} ->
-        reversed = reversed_post ++ reversed_pre
-
-        case codepoint_cursor_context(reversed, opts) do
-          {{:alias, acc}, offset} ->
-            build_surround({:alias, acc}, reversed, line, offset)
-
-          {{:struct, acc}, offset} ->
-            build_surround({:struct, acc}, reversed, line, offset)
-
-          _ ->
-            :none
-        end
-    end
-  end
-
-  defp maybe_operator(reversed_pre, post, line, opts) do
-    case take_operator(post, []) do
-      {[], _rest} ->
-        :none
-
-      {reversed_post, rest} ->
-        reversed = reversed_post ++ reversed_pre
-
-        case codepoint_cursor_context(reversed, opts) do
-          {{:operator, acc}, offset} when acc not in @incomplete_operators ->
-            build_surround({:operator, acc}, reversed, line, offset)
-
-          {{:sigil, ''}, offset} when hd(rest) in ?A..?Z or hd(rest) in ?a..?z ->
-            build_surround({:sigil, [hd(rest)]}, [hd(rest) | reversed], line, offset + 1)
-
-          {{:dot, _, [_ | _]} = dot, offset} ->
-            build_surround(dot, reversed, line, offset)
-
-          _ ->
-            :none
-        end
-    end
-  end
-
-  defp build_surround(context, reversed, line, offset) do
-    {post, reversed_pre} = enum_reverse_at(reversed, offset, [])
-    pre = :lists.reverse(reversed_pre)
-    pre_length = :string.length(pre) + 1
-
-    %{
-      context: context,
-      begin: {line, pre_length},
-      end: {line, pre_length + :string.length(post)}
-    }
-  end
-
-  defp take_identifier([h | t], acc) when h in @trailing_identifier,
-    do: {:identifier, [h | acc], t}
-
-  defp take_identifier([h | t], acc) when h not in @non_identifier,
-    do: take_identifier(t, [h | acc])
-
-  defp take_identifier(rest, acc) do
-    with {[?. | t], _} <- strip_spaces(rest, 0),
-         {[h | _], _} when h in ?A..?Z <- strip_spaces(t, 0) do
-      take_alias(rest, acc)
-    else
-      _ -> {:identifier, acc, rest}
-    end
-  end
-
-  defp take_alias([h | t], acc) when h not in @non_identifier,
-    do: take_alias(t, [h | acc])
-
-  defp take_alias(rest, acc) do
-    with {[?. | t], acc} <- move_spaces(rest, acc),
-         {[h | t], acc} when h in ?A..?Z <- move_spaces(t, [?. | acc]) do
-      take_alias(t, [h | acc])
-    else
-      _ -> {:alias, acc, rest}
-    end
-  end
-
-  defp take_operator([h | t], acc) when h in @operators, do: take_operator(t, [h | acc])
-  defp take_operator([h | t], acc) when h == ?., do: take_operator(t, [h | acc])
-  defp take_operator(rest, acc), do: {acc, rest}
-
-  # Unquoted atom handling
-  defp adjust_position(reversed_pre, [?: | post])
-       when hd(post) != ?: and (reversed_pre == [] or hd(reversed_pre) != ?:) do
-    {[?: | reversed_pre], post}
-  end
-
-  defp adjust_position(reversed_pre, [?% | post]) do
-    adjust_position([?% | reversed_pre], post)
-  end
-
-  # Dot/struct handling
-  defp adjust_position(reversed_pre, post) do
-    case move_spaces(post, reversed_pre) do
-      # If we are between spaces and a dot, move past the dot
-      {[?. | post], reversed_pre} when hd(post) != ?. and hd(reversed_pre) != ?. ->
-        {post, reversed_pre} = move_spaces(post, [?. | reversed_pre])
-        {reversed_pre, post}
-
-      _ ->
-        case strip_spaces(reversed_pre, 0) do
-          # If there is a dot to our left, make sure to move to the first character
-          {[?. | rest], _} when rest == [] or hd(rest) not in '.:' ->
-            {post, reversed_pre} = move_spaces(post, reversed_pre)
-            {reversed_pre, post}
-
-          # If there is a % to our left, make sure to move to the first character
-          {[?% | _], _} ->
-            case move_spaces(post, reversed_pre) do
-              {[h | _] = post, reversed_pre} when h in ?A..?Z ->
-                {reversed_pre, post}
-
-              _ ->
-                {reversed_pre, post}
-            end
-
-          _ ->
-            {reversed_pre, post}
-        end
-    end
-  end
-
-  defp move_spaces([h | t], acc) when h in @space, do: move_spaces(t, [h | acc])
-  defp move_spaces(t, acc), do: {t, acc}
-
-  defp string_reverse_at(charlist, 0, acc), do: {acc, charlist}
-
-  defp string_reverse_at(charlist, n, acc) do
-    case :unicode_util.gc(charlist) do
-      [gc | cont] when is_integer(gc) -> string_reverse_at(cont, n - 1, [gc | acc])
-      [gc | cont] when is_list(gc) -> string_reverse_at(cont, n - 1, :lists.reverse(gc, acc))
-      [] -> {acc, []}
-    end
-  end
-
-  defp enum_reverse_at([h | t], n, acc) when n > 0, do: enum_reverse_at(t, n - 1, [h | acc])
-  defp enum_reverse_at(rest, _, acc), do: {acc, rest}
-
-  @doc """
-  Receives a code fragment and returns a quoted expression
-  with a cursor at the nearest argument position.
-
-  A container is any Elixir expression starting with `(`,
-  `{`, and `[`. This includes function calls, tuples, lists,
-  maps, and so on. For example, take this code, which would
-  be given as input:
-
-      max(some_value,
-
-  This function will return the AST equivalent to:
-
-      max(some_value, __cursor__())
-
-  In other words, this function is capable of closing any open
-  brackets and insert the cursor position. Any content at the
-  cursor position that is after a comma or an opening bracket
-  is discarded. For example, if this is given as input:
-
-      max(some_value, another_val
-
-  It will return the same AST:
-
-      max(some_value, __cursor__())
-
-  Similarly, if only this is given:
-
-      max(some_va
-
-  Then it returns:
-
-      max(__cursor__())
-
-  Calls without parenthesis are also supported, as we assume the
-  brackets are implicit.
-
-  Operators and anonymous functions are not containers, and therefore
-  will be discarded. The following will all return the same AST:
-
-      max(some_value,
-      max(some_value, fn x -> x end
-      max(some_value, 1 + another_val
-      max(some_value, 1 |> some_fun() |> another_fun
-
-  On the other hand, tuples, lists, maps, etc all retain the
-  cursor position:
-
-      max(some_value, [1, 2,
-
-  Returns the following AST:
-
-      max(some_value, [1, 2, __cursor__()])
-
-  Keyword lists (and do-end blocks) are also retained. The following:
-
-      if(some_value, do:
-      if(some_value, do: :token
-      if(some_value, do: 1 + val
-
-  all return:
-
-      if(some_value, do: __cursor__())
-
-  The AST returned by this function is not safe to evaluate but
-  it can be analyzed and expanded.
-
-  ## Examples
-
-      iex> Code.Fragment.container_cursor_to_quoted("max(some_value, ")
-      {:ok, {:max, [line: 1], [{:some_value, [line: 1], nil}, {:__cursor__, [line: 1], []}]}}
-
-  ## Options
-
-    * `:file` - the filename to be reported in case of parsing errors.
-      Defaults to `"nofile"`.
-
-    * `:line` - the starting line of the string being parsed.
-      Defaults to 1.
-
-    * `:column` - the starting column of the string being parsed.
-      Defaults to 1.
-
-    * `:columns` - when `true`, attach a `:column` key to the quoted
-      metadata. Defaults to `false`.
-
-    * `:token_metadata` - when `true`, includes token-related
-      metadata in the expression AST, such as metadata for `do` and `end`
-      tokens, for closing tokens, end of expressions, as well as delimiters
-      for sigils. See `t:Macro.metadata/0`. Defaults to `false`.
-
-  """
-  @doc since: "1.13.0"
-  @spec container_cursor_to_quoted(List.Chars.t(), keyword()) ::
-          {:ok, Macro.t()} | {:error, {location :: keyword, binary | {binary, binary}, binary}}
-  def container_cursor_to_quoted(fragment, opts \\ []) do
-    file = Keyword.get(opts, :file, "nofile")
-    line = Keyword.get(opts, :line, 1)
-    column = Keyword.get(opts, :column, 1)
-    columns = Keyword.get(opts, :columns, false)
-    token_metadata = Keyword.get(opts, :token_metadata, false)
-
-    fragment = to_charlist(fragment)
-    tokenizer_opts = [file: file, cursor_completion: true, columns: columns]
-
-    case :elixir_tokenizer.tokenize(fragment, line, column, tokenizer_opts) do
-      {:ok, _, _, _warnings, tokens} ->
-        :elixir.tokens_to_quoted(tokens, nil, columns: columns, token_metadata: token_metadata)
-
-      {:error, {line, column, {prefix, suffix}, token}, _rest, _warnings, _so_far} ->
-        location = [line: line, column: column]
-        {:error, {location, {to_string(prefix), to_string(suffix)}, to_string(token)}}
-
-      {:error, {line, column, error, token}, _rest, _warnings, _so_far} ->
-        location = [line: line, column: column]
-        {:error, {location, to_string(error), to_string(token)}}
-    end
-  end
-end

lib/elixir/lib/code/identifier.ex

@@ -1,291 +0,0 @@
-defmodule Code.Identifier do
-  @moduledoc false
-
-  @doc """
-  Checks if the given identifier is an unary op.
-
-  ## Examples
-
-      iex> Code.Identifier.unary_op(:+)
-      {:non_associative, 300}
-
-  """
-  @spec unary_op(atom) :: {:non_associative, precedence :: pos_integer} | :error
-  def unary_op(op) do
-    cond do
-      op in [:&] -> {:non_associative, 90}
-      op in [:!, :^, :not, :+, :-, :~~~] -> {:non_associative, 300}
-      op in [:@] -> {:non_associative, 320}
-      true -> :error
-    end
-  end
-
-  @doc """
-  Checks if the given identifier is a binary op.
-
-  ## Examples
-
-      iex> Code.Identifier.binary_op(:+)
-      {:left, 210}
-
-  """
-  @spec binary_op(atom) :: {:left | :right, precedence :: pos_integer} | :error
-  def binary_op(op) do
-    cond do
-      op in [:<-, :\\] -> {:left, 40}
-      op in [:when] -> {:right, 50}
-      op in [:"::"] -> {:right, 60}
-      op in [:|] -> {:right, 70}
-      op in [:=] -> {:right, 100}
-      op in [:||, :|||, :or] -> {:left, 120}
-      op in [:&&, :&&&, :and] -> {:left, 130}
-      op in [:==, :!=, :=~, :===, :!==] -> {:left, 140}
-      op in [:<, :<=, :>=, :>] -> {:left, 150}
-      op in [:|>, :<<<, :>>>, :<~, :~>, :<<~, :~>>, :<~>, :<|>] -> {:left, 160}
-      op in [:in] -> {:left, 170}
-      op in [:^^^] -> {:left, 180}
-      op in [:"//"] -> {:right, 190}
-      op in [:++, :--, :.., :<>, :+++, :---] -> {:right, 200}
-      op in [:+, :-] -> {:left, 210}
-      op in [:*, :/] -> {:left, 220}
-      op in [:**] -> {:left, 230}
-      op in [:.] -> {:left, 310}
-      true -> :error
-    end
-  end
-
-  @doc """
-  Classifies the given atom into one of the following categories:
-
-    * `:alias` - a valid Elixir alias, like `Foo`, `Foo.Bar` and so on
-
-    * `:callable_local` - an atom that can be used as a local call;
-      this category includes identifiers like `:foo`
-
-    * `:callable_operator` - all callable operators, such as `:<>`. Note
-      operators such as `:..` are not callable because of ambiguity
-
-    * `:not_atomable` - callable operators that must be wrapped in quotes when
-      defined as an atom. For example, `::` must be written as `:"::"` to avoid
-      the ambiguity between the atom and the keyword identifier
-
-    * `:not_callable` - an atom that cannot be used as a function call after the
-      `.` operator. Those are typically AST nodes that are special forms (such as
-      `:%{}` and `:<<>>>`) as well as nodes that are ambiguous in calls (such as
-      `:..` and `:...`). This category also includes atoms like `:Foo`, since
-      they are valid identifiers but they need quotes to be used in function
-      calls (`Foo."Bar"`)
-
-    * `:other` - any other atom (these are usually escaped when inspected, like
-      `:"foo and bar"`)
-
-  """
-  def classify(atom) when is_atom(atom) do
-    charlist = Atom.to_charlist(atom)
-
-    cond do
-      atom in [:%, :%{}, :{}, :<<>>, :..., :.., :., :"..//", :->] ->
-        :not_callable
-
-      atom in [:"::", :"//"] ->
-        :not_atomable
-
-      unary_op(atom) != :error or binary_op(atom) != :error ->
-        :callable_operator
-
-      valid_alias?(charlist) ->
-        :alias
-
-      true ->
-        case :elixir_config.identifier_tokenizer().tokenize(charlist) do
-          {kind, _acc, [], _, _, special} ->
-            if kind == :identifier and not :lists.member(?@, special) do
-              :callable_local
-            else
-              :not_callable
-            end
-
-          _ ->
-            :other
-        end
-    end
-  end
-
-  defp valid_alias?('Elixir' ++ rest), do: valid_alias_piece?(rest)
-  defp valid_alias?(_other), do: false
-
-  defp valid_alias_piece?([?., char | rest]) when char >= ?A and char <= ?Z,
-    do: valid_alias_piece?(trim_leading_while_valid_identifier(rest))
-
-  defp valid_alias_piece?([]), do: true
-  defp valid_alias_piece?(_other), do: false
-
-  defp trim_leading_while_valid_identifier([char | rest])
-       when char >= ?a and char <= ?z
-       when char >= ?A and char <= ?Z
-       when char >= ?0 and char <= ?9
-       when char == ?_ do
-    trim_leading_while_valid_identifier(rest)
-  end
-
-  defp trim_leading_while_valid_identifier(other) do
-    other
-  end
-
-  @doc """
-  Inspects the identifier as an atom.
-  """
-  def inspect_as_atom(atom) when is_nil(atom) or is_boolean(atom) do
-    Atom.to_string(atom)
-  end
-
-  def inspect_as_atom(atom) when is_atom(atom) do
-    binary = Atom.to_string(atom)
-
-    case classify(atom) do
-      :alias ->
-        case binary do
-          binary when binary in ["Elixir", "Elixir.Elixir"] -> binary
-          "Elixir.Elixir." <> _rest -> binary
-          "Elixir." <> rest -> rest
-        end
-
-      type when type in [:callable_local, :callable_operator, :not_callable] ->
-        ":" <> binary
-
-      _ ->
-        {escaped, _} = escape(binary, ?")
-        IO.iodata_to_binary([?:, ?", escaped, ?"])
-    end
-  end
-
-  @doc """
-  Inspects the given identifier as a key.
-  """
-  def inspect_as_key(atom) when is_atom(atom) do
-    binary = Atom.to_string(atom)
-
-    case classify(atom) do
-      type when type in [:callable_local, :callable_operator, :not_callable] ->
-        IO.iodata_to_binary([binary, ?:])
-
-      _ ->
-        {escaped, _} = escape(binary, ?")
-        IO.iodata_to_binary([?", escaped, ?", ?:])
-    end
-  end
-
-  @doc """
-  Inspects the given identifier as a function name.
-  """
-  def inspect_as_function(atom) when is_atom(atom) do
-    binary = Atom.to_string(atom)
-
-    case classify(atom) do
-      type when type in [:callable_local, :callable_operator, :not_atomable] ->
-        binary
-
-      type ->
-        escaped =
-          if type in [:not_callable, :alias] do
-            binary
-          else
-            elem(escape(binary, ?"), 0)
-          end
-
-        IO.iodata_to_binary([?", escaped, ?"])
-    end
-  end
-
-  @doc """
-  Extracts the name and arity of the parent from the anonymous function identifier.
-  """
-  # Example of this format: -NAME/ARITY-fun-COUNT-
-  def extract_anonymous_fun_parent(atom) when is_atom(atom) do
-    with "-" <> rest <- Atom.to_string(atom),
-         [trailing | reversed] = rest |> String.split("/") |> Enum.reverse(),
-         [arity, _inner, _count, ""] <- String.split(trailing, "-") do
-      {reversed |> Enum.reverse() |> Enum.join("/") |> String.to_atom(), arity}
-    else
-      _ -> :error
-    end
-  end
-
-  @doc """
-  Escapes the given identifier.
-  """
-  def escape(other, char, count \\ :infinity, fun \\ &escape_map/1) do
-    escape(other, char, count, [], fun)
-  end
-
-  defp escape(<<_, _::binary>> = binary, _char, 0, acc, _fun) do
-    {acc, binary}
-  end
-
-  defp escape(<<char, t::binary>>, char, count, acc, fun) do
-    escape(t, char, decrement(count), [acc | [?\\, char]], fun)
-  end
-
-  defp escape(<<?#, ?{, t::binary>>, char, count, acc, fun) do
-    escape(t, char, decrement(count), [acc | '\\\#{'], fun)
-  end
-
-  defp escape(<<h::utf8, t::binary>>, char, count, acc, fun) do
-    escaped = if value = fun.(h), do: value, else: escape_char(h)
-    escape(t, char, decrement(count), [acc | escaped], fun)
-  end
-
-  defp escape(<<a::4, b::4, t::binary>>, char, count, acc, fun) do
-    escape(t, char, decrement(count), [acc | ['\\x', to_hex(a), to_hex(b)]], fun)
-  end
-
-  defp escape(<<>>, _char, _count, acc, _fun) do
-    {acc, <<>>}
-  end
-
-  defp escape_char(0), do: '\\0'
-
-  defp escape_char(65279), do: '\\uFEFF'
-
-  defp escape_char(char)
-       when char in 0x20..0x7E
-       when char in 0xA0..0xD7FF
-       when char in 0xE000..0xFFFD
-       when char in 0x10000..0x10FFFF do
-    <<char::utf8>>
-  end
-
-  defp escape_char(char) when char < 0x100 do
-    <<a::4, b::4>> = <<char::8>>
-    ['\\x', to_hex(a), to_hex(b)]
-  end
-
-  defp escape_char(char) when char < 0x10000 do
-    <<a::4, b::4, c::4, d::4>> = <<char::16>>
-    ['\\x{', to_hex(a), to_hex(b), to_hex(c), to_hex(d), ?}]
-  end
-
-  defp escape_char(char) when char < 0x1000000 do
-    <<a::4, b::4, c::4, d::4, e::4, f::4>> = <<char::24>>
-    ['\\x{', to_hex(a), to_hex(b), to_hex(c), to_hex(d), to_hex(e), to_hex(f), ?}]
-  end
-
-  defp escape_map(?\a), do: '\\a'
-  defp escape_map(?\b), do: '\\b'
-  defp escape_map(?\d), do: '\\d'
-  defp escape_map(?\e), do: '\\e'
-  defp escape_map(?\f), do: '\\f'
-  defp escape_map(?\n), do: '\\n'
-  defp escape_map(?\r), do: '\\r'
-  defp escape_map(?\t), do: '\\t'
-  defp escape_map(?\v), do: '\\v'
-  defp escape_map(?\\), do: '\\\\'
-  defp escape_map(_), do: false
-
-  @compile {:inline, to_hex: 1, decrement: 1}
-  defp to_hex(c) when c in 0..9, do: ?0 + c
-  defp to_hex(c) when c in 10..15, do: ?A + c - 10
-
-  defp decrement(:infinity), do: :infinity
-  defp decrement(counter), do: counter - 1
-end

lib/elixir/lib/code/normalizer.ex

@@ -1,585 +0,0 @@
-defmodule Code.Normalizer do
-  @moduledoc false
-
-  defguard is_literal(x)
-           when is_integer(x) or
-                  is_float(x) or
-                  is_binary(x) or
-                  is_atom(x)
-
-  @doc """
-  Wraps literals in the quoted expression to conform to the AST format expected
-  by the formatter.
-  """
-  def normalize(quoted, opts \\ []) do
-    line = Keyword.get(opts, :line, nil)
-    escape = Keyword.get(opts, :escape, true)
-    locals_without_parens = Keyword.get(opts, :locals_without_parens, [])
-
-    state = %{
-      escape: escape,
-      parent_meta: [line: line],
-      locals_without_parens: locals_without_parens ++ Code.Formatter.locals_without_parens()
-    }
-
-    do_normalize(quoted, state)
-  end
-
-  # Wrapped literals should receive the block meta
-  defp do_normalize({:__block__, meta, [literal]}, state)
-       when not is_tuple(literal) or tuple_size(literal) == 2 do
-    normalize_literal(literal, meta, state)
-  end
-
-  # Only normalize the first argument of an alias if it's not an atom
-  defp do_normalize({:__aliases__, meta, [first | rest]}, state) when not is_atom(first) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    first = do_normalize(first, %{state | parent_meta: meta})
-    {:__aliases__, meta, [first | rest]}
-  end
-
-  defp do_normalize({:__aliases__, _, _} = quoted, _state) do
-    quoted
-  end
-
-  # Skip captured arguments like &1
-  defp do_normalize({:&, meta, [term]}, state) when is_integer(term) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    {:&, meta, [term]}
-  end
-
-  # Ranges
-  defp do_normalize(left..right//step, state) do
-    left = do_normalize(left, state)
-    right = do_normalize(right, state)
-    meta = meta_line(state)
-
-    if step == 1 do
-      {:.., meta, [left, right]}
-    else
-      step = do_normalize(step, state)
-      {:"..//", meta, [left, right, step]}
-    end
-  end
-
-  # Bit containers
-  defp do_normalize({:<<>>, _, args} = quoted, state) when is_list(args) do
-    normalize_bitstring(quoted, state)
-  end
-
-  # Atoms with interpolations
-  defp do_normalize(
-         {{:., dot_meta, [:erlang, :binary_to_atom]}, call_meta,
-          [{:<<>>, _, args} = string, :utf8]},
-         state
-       )
-       when is_list(args) do
-    dot_meta = patch_meta_line(dot_meta, state.parent_meta)
-    call_meta = patch_meta_line(call_meta, dot_meta)
-
-    string =
-      if state.escape do
-        normalize_bitstring(string, state, true)
-      else
-        normalize_bitstring(string, state)
-      end
-
-    {{:., dot_meta, [:erlang, :binary_to_atom]}, call_meta, [string, :utf8]}
-  end
-
-  # Charlists with interpolations
-  defp do_normalize({{:., dot_meta, [List, :to_charlist]}, call_meta, [parts]}, state) do
-    parts =
-      Enum.map(parts, fn
-        {{:., part_dot_meta, [Kernel, :to_string]}, part_call_meta, args} ->
-          args = normalize_args(args, state)
-
-          {{:., part_dot_meta, [Kernel, :to_string]}, part_call_meta, args}
-
-        part ->
-          if state.escape do
-            maybe_escape_literal(part, state)
-          else
-            part
-          end
-      end)
-
-    {{:., dot_meta, [List, :to_charlist]}, call_meta, [parts]}
-  end
-
-  # Don't normalize the `Access` atom in access syntax
-  defp do_normalize({:., meta, [Access, :get]}, state) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    {:., meta, [Access, :get]}
-  end
-
-  # Only normalize the left side of the dot operator
-  # The right hand side is an atom in the AST but it's not an atom literal, so
-  # it should not be wrapped
-  defp do_normalize({:., meta, [left, right]}, state) do
-    meta = patch_meta_line(meta, state.parent_meta)
-
-    left = do_normalize(left, %{state | parent_meta: meta})
-
-    {:., meta, [left, right]}
-  end
-
-  # A list of left to right arrows is not considered as a list literal, so it's not wrapped
-  defp do_normalize([{:->, _, [_ | _]} | _] = quoted, state) do
-    normalize_args(quoted, state)
-  end
-
-  # left -> right
-  defp do_normalize({:->, meta, [left, right]}, state) do
-    meta = patch_meta_line(meta, state.parent_meta)
-
-    left = normalize_args(left, %{state | parent_meta: meta})
-    right = do_normalize(right, %{state | parent_meta: meta})
-    {:->, meta, [left, right]}
-  end
-
-  # Maps
-  defp do_normalize({:%{}, meta, args}, state) when is_list(args) do
-    meta =
-      if meta == [] do
-        line = state.parent_meta[:line]
-        [line: line, closing: [line: line]]
-      else
-        meta
-      end
-
-    state = %{state | parent_meta: meta}
-
-    args =
-      case args do
-        [{:|, pipe_meta, [left, right]}] ->
-          left = do_normalize(left, state)
-          right = normalize_map_args(right, state)
-          [{:|, pipe_meta, [left, right]}]
-
-        [{_, _, _} = call] ->
-          [do_normalize(call, state)]
-
-        args ->
-          normalize_map_args(args, state)
-      end
-
-    {:%{}, meta, args}
-  end
-
-  # Sigils
-  defp do_normalize({sigil, meta, [{:<<>>, _, args} = string, modifiers]} = quoted, state)
-       when is_list(args) and is_atom(sigil) do
-    case Atom.to_string(sigil) do
-      <<"sigil_", _name>> ->
-        meta =
-          meta
-          |> patch_meta_line(state.parent_meta)
-          |> Keyword.put_new(:delimiter, "\"")
-
-        {sigil, meta, [do_normalize(string, %{state | parent_meta: meta}), modifiers]}
-
-      _ ->
-        normalize_call(quoted, state)
-    end
-  end
-
-  # Tuples
-  defp do_normalize({:{}, meta, args} = quoted, state) when is_list(args) do
-    {last_arg, args} = List.pop_at(args, -1)
-
-    if args != [] and match?([_ | _], last_arg) and keyword?(last_arg) do
-      args = normalize_args(args, state)
-      kw_list = normalize_kw_args(last_arg, state, true)
-      {:{}, meta, args ++ kw_list}
-    else
-      normalize_call(quoted, state)
-    end
-  end
-
-  # Module attributes
-  defp do_normalize({:@, meta, [{name, name_meta, [value]}]}, state) do
-    value =
-      cond do
-        keyword?(value) ->
-          normalize_kw_args(value, state, true)
-
-        is_list(value) ->
-          normalize_literal(value, meta, state)
-
-        true ->
-          do_normalize(value, state)
-      end
-
-    {:@, meta, [{name, name_meta, [value]}]}
-  end
-
-  # Regular blocks
-  defp do_normalize({:__block__, meta, args}, state) when is_list(args) do
-    {:__block__, meta, normalize_args(args, state)}
-  end
-
-  # Calls
-  defp do_normalize({_, _, args} = quoted, state) when is_list(args) do
-    normalize_call(quoted, state)
-  end
-
-  # Vars
-  defp do_normalize({_, _, context} = quoted, _state) when is_atom(context) do
-    quoted
-  end
-
-  # Literals
-  defp do_normalize(quoted, state) do
-    normalize_literal(quoted, [], state)
-  end
-
-  # Numbers
-  defp normalize_literal(number, meta, state) when is_number(number) do
-    meta =
-      meta
-      |> Keyword.put_new(:token, inspect(number))
-      |> patch_meta_line(state.parent_meta)
-
-    {:__block__, meta, [number]}
-  end
-
-  # Atom, Strings
-  defp normalize_literal(literal, meta, state) when is_atom(literal) or is_binary(literal) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    literal = maybe_escape_literal(literal, state)
-
-    if is_atom(literal) and Code.Identifier.classify(literal) == :alias and
-         is_nil(meta[:delimiter]) do
-      segments =
-        case Atom.to_string(literal) do
-          "Elixir" ->
-            [:"Elixir"]
-
-          "Elixir." <> segments ->
-            segments
-            |> String.split(".")
-            |> Enum.map(&String.to_atom/1)
-        end
-
-      {:__aliases__, meta, segments}
-    else
-      {:__block__, meta, [literal]}
-    end
-  end
-
-  # 2-tuples
-  defp normalize_literal({left, right}, meta, state) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    state = %{state | parent_meta: meta}
-
-    if match?([_ | _], right) and keyword?(right) do
-      {:__block__, meta, [{do_normalize(left, state), normalize_kw_args(right, state, true)}]}
-    else
-      {:__block__, meta, [{do_normalize(left, state), do_normalize(right, state)}]}
-    end
-  end
-
-  # Lists
-  defp normalize_literal(list, meta, state) when is_list(list) do
-    if list != [] and List.ascii_printable?(list) do
-      # It's a charlist
-      list =
-        if state.escape do
-          {string, _} = Code.Identifier.escape(IO.chardata_to_string(list), -1)
-          IO.iodata_to_binary(string) |> to_charlist()
-        else
-          list
-        end
-
-      meta =
-        meta
-        |> Keyword.put_new(:delimiter, "'")
-        |> patch_meta_line(state.parent_meta)
-
-      {:__block__, meta, [list]}
-    else
-      meta =
-        if line = state.parent_meta[:line] do
-          meta
-          |> Keyword.put_new(:closing, line: line)
-          |> patch_meta_line(state.parent_meta)
-        else
-          meta
-        end
-
-      {:__block__, meta, [normalize_kw_args(list, state, false)]}
-    end
-  end
-
-  # Probably an invalid value, wrap it and send it upstream
-  defp normalize_literal(quoted, meta, _state) do
-    {:__block__, meta, [quoted]}
-  end
-
-  defp normalize_call({form, meta, args}, state) do
-    meta = patch_meta_line(meta, state.parent_meta)
-    arity = length(args)
-
-    # Only normalize the form if it's a qualified call
-    form =
-      if is_atom(form) do
-        form
-      else
-        do_normalize(form, %{state | parent_meta: meta})
-      end
-
-    meta =
-      if is_nil(meta[:no_parens]) and is_nil(meta[:closing]) and is_nil(meta[:do]) and
-           not Code.Formatter.local_without_parens?(form, arity, state.locals_without_parens) do
-        [closing: [line: meta[:line]]] ++ meta
-      else
-        meta
-      end
-
-    cond do
-      Keyword.has_key?(meta, :do) or match?([{{:__block__, _, [:do]}, _} | _], List.last(args)) ->
-        # def foo do :ok end
-        # def foo, do: :ok
-        normalize_kw_blocks(form, meta, args, state)
-
-      match?([{:do, _} | _], List.last(args)) ->
-        # Non normalized kw blocks
-        line = state.parent_meta[:line]
-        meta = meta ++ [do: [line: line], end: [line: line]]
-        normalize_kw_blocks(form, meta, args, state)
-
-      allow_keyword?(form, arity) ->
-        args = normalize_args(args, %{state | parent_meta: state.parent_meta})
-        {last_arg, leading_args} = List.pop_at(args, -1, [])
-
-        last_args =
-          case last_arg do
-            {:__block__, _, [[{{:__block__, key_meta, _}, _} | _]] = last_args} ->
-              if key_meta[:format] == :keyword do
-                last_args
-              else
-                [last_arg]
-              end
-
-            [] ->
-              []
-
-            _ ->
-              [last_arg]
-          end
-
-        {form, meta, leading_args ++ last_args}
-
-      true ->
-        args = normalize_args(args, %{state | parent_meta: state.parent_meta})
-        {form, meta, args}
-    end
-  end
-
-  defp allow_keyword?(:when, 2), do: true
-  defp allow_keyword?(:{}, _), do: false
-  defp allow_keyword?(op, arity), do: not is_atom(op) or not Macro.operator?(op, arity)
-
-  defp normalize_bitstring({:<<>>, meta, parts} = quoted, state, escape_interpolation \\ false) do
-    meta = patch_meta_line(meta, state.parent_meta)
-
-    parts =
-      if interpolated?(quoted) do
-        normalize_interpolation_parts(parts, %{state | parent_meta: meta}, escape_interpolation)
-      else
-        state = %{state | parent_meta: meta}
-
-        Enum.map(parts, fn part ->
-          with {:"::", meta, [left, _]} <- part,
-               true <- meta[:inferred_bitstring_spec] do
-            do_normalize(left, state)
-          else
-            _ -> do_normalize(part, state)
-          end
-        end)
-      end
-
-    {:<<>>, meta, parts}
-  end
-
-  defp normalize_interpolation_parts(parts, state, escape_interpolation) do
-    Enum.map(parts, fn
-      {:"::", interpolation_meta,
-       [
-         {{:., dot_meta, [Kernel, :to_string]}, middle_meta, [middle]},
-         {:binary, binary_meta, context}
-       ]} ->
-        middle = do_normalize(middle, %{state | parent_meta: dot_meta})
-
-        {:"::", interpolation_meta,
-         [
-           {{:., dot_meta, [Kernel, :to_string]}, middle_meta, [middle]},
-           {:binary, binary_meta, context}
-         ]}
-
-      part ->
-        if escape_interpolation do
-          maybe_escape_literal(part, state)
-        else
-          part
-        end
-    end)
-  end
-
-  defp normalize_map_args(args, state) do
-    Enum.map(normalize_kw_args(args, state, false), fn
-      {:__block__, _, [{_, _} = pair]} -> pair
-      pair -> pair
-    end)
-  end
-
-  defp normalize_kw_blocks(form, meta, args, state) do
-    {kw_blocks, leading_args} = List.pop_at(args, -1)
-
-    kw_blocks =
-      Enum.map(kw_blocks, fn {tag, block} ->
-        block = do_normalize(block, %{state | parent_meta: meta})
-
-        block =
-          case block do
-            {_, _, [[{:->, _, _} | _] = block]} -> block
-            block -> block
-          end
-
-        # Only wrap the tag if it isn't already wrapped
-        tag =
-          case tag do
-            {:__block__, _, _} -> tag
-            _ -> {:__block__, [line: meta[:line]], [tag]}
-          end
-
-        {tag, block}
-      end)
-
-    leading_args = normalize_args(leading_args, %{state | parent_meta: meta})
-    {form, meta, leading_args ++ [kw_blocks]}
-  end
-
-  defp normalize_kw_args(elems, state, keyword?)
-
-  defp normalize_kw_args(
-         [{{:__block__, key_meta, [key]}, value} = first | rest] = current,
-         state,
-         keyword?
-       )
-       when is_atom(key) do
-    keyword? = keyword? or keyword?(current)
-
-    first =
-      if key_meta[:format] == :keyword and not keyword? do
-        key_meta = Keyword.delete(key_meta, :format)
-        line = key_meta[:line] || meta_line(state)
-        {:__block__, [line: line], [{{:__block__, key_meta, [key]}, value}]}
-      else
-        first
-      end
-
-    [first | normalize_kw_args(rest, state, keyword?)]
-  end
-
-  defp normalize_kw_args([{left, right} | rest] = current, state, keyword?) do
-    keyword? = keyword? or keyword?(current)
-
-    left =
-      if keyword? do
-        meta = [format: :keyword] ++ meta_line(state)
-        {:__block__, meta, [maybe_escape_literal(left, state)]}
-      else
-        do_normalize(left, state)
-      end
-
-    right = do_normalize(right, state)
-
-    pair =
-      with {:__block__, meta, _} <- left,
-           :keyword <- meta[:format] do
-        {left, right}
-      else
-        _ -> {:__block__, meta_line(state), [{left, right}]}
-      end
-
-    [pair | normalize_kw_args(rest, state, keyword?)]
-  end
-
-  defp normalize_kw_args([first | rest], state, keyword?) do
-    [do_normalize(first, state) | normalize_kw_args(rest, state, keyword?)]
-  end
-
-  defp normalize_kw_args([], _state, _keyword?) do
-    []
-  end
-
-  defp normalize_args(args, state) do
-    Enum.map(args, &do_normalize(&1, state))
-  end
-
-  defp maybe_escape_literal(string, %{escape: true}) when is_binary(string) do
-    {string, _} = Code.Identifier.escape(string, -1)
-    IO.iodata_to_binary(string)
-  end
-
-  defp maybe_escape_literal(atom, %{escape: true} = state) when is_atom(atom) do
-    atom
-    |> Atom.to_string()
-    |> maybe_escape_literal(state)
-    |> String.to_atom()
-  end
-
-  defp maybe_escape_literal(term, _) do
-    term
-  end
-
-  # Check if we have an interpolated string.
-  defp interpolated?({:<<>>, _, [_ | _] = parts}) do
-    Enum.all?(parts, fn
-      {:"::", _, [{{:., _, [Kernel, :to_string]}, _, [_]}, {:binary, _, _}]} -> true
-      binary when is_binary(binary) -> true
-      _ -> false
-    end)
-  end
-
-  defp interpolated?(_) do
-    false
-  end
-
-  defp patch_meta_line(meta, parent_meta) do
-    with nil <- meta[:line],
-         line when is_integer(line) <- parent_meta[:line] do
-      [line: line] ++ meta
-    else
-      _ -> meta
-    end
-  end
-
-  defp meta_line(state) do
-    if line = state.parent_meta[:line] do
-      [line: line]
-    else
-      []
-    end
-  end
-
-  defp keyword?([{{:__block__, key_meta, [key]}, _} | rest]) when is_atom(key) do
-    if key_meta[:format] == :keyword do
-      keyword?(rest)
-    else
-      false
-    end
-  end
-
-  defp keyword?([{key, _value} | rest]) when is_atom(key) do
-    case Atom.to_charlist(key) do
-      'Elixir.' ++ _ -> false
-      _ -> keyword?(rest)
-    end
-  end
-
-  defp keyword?([]), do: true
-  defp keyword?(_other), do: false
-end

lib/elixir/lib/code/typespec.ex

@@ -1,421 +0,0 @@
-defmodule Code.Typespec do
-  @moduledoc false
-
-  @doc """
-  Converts a spec clause back to Elixir quoted expression.
-  """
-  @spec spec_to_quoted(atom, tuple) :: {atom, keyword, [Macro.t()]}
-  def spec_to_quoted(name, spec)
-
-  def spec_to_quoted(name, {:type, anno, :fun, [{:type, _, :product, args}, result]})
-      when is_atom(name) do
-    meta = meta(anno)
-    body = {name, meta, Enum.map(args, &typespec_to_quoted/1)}
-
-    vars =
-      for type_expr <- args ++ [result],
-          var <- collect_vars(type_expr),
-          uniq: true,
-          do: {var, {:var, meta, nil}}
-
-    spec = {:"::", meta, [body, typespec_to_quoted(result)]}
-
-    if vars == [] do
-      spec
-    else
-      {:when, meta, [spec, vars]}
-    end
-  end
-
-  def spec_to_quoted(name, {:type, anno, :fun, []}) when is_atom(name) do
-    meta = meta(anno)
-    {:"::", meta, [{name, meta, []}, quote(do: term)]}
-  end
-
-  def spec_to_quoted(name, {:type, anno, :bounded_fun, [type, constrs]}) when is_atom(name) do
-    meta = meta(anno)
-    {:type, _, :fun, [{:type, _, :product, args}, result]} = type
-
-    guards =
-      for {:type, _, :constraint, [{:atom, _, :is_subtype}, [{:var, _, var}, type]]} <- constrs do
-        {erl_to_ex_var(var), typespec_to_quoted(type)}
-      end
-
-    ignore_vars = Keyword.keys(guards)
-
-    vars =
-      for type_expr <- args ++ [result],
-          var <- collect_vars(type_expr),
-          var not in ignore_vars,
-          uniq: true,
-          do: {var, {:var, meta, nil}}
-
-    args = for arg <- args, do: typespec_to_quoted(arg)
-
-    when_args = [
-      {:"::", meta, [{name, meta, args}, typespec_to_quoted(result)]},
-      guards ++ vars
-    ]
-
-    {:when, meta, when_args}
-  end
-
-  @doc """
-  Converts a type clause back to Elixir AST.
-  """
-  def type_to_quoted(type)
-
-  def type_to_quoted({{:record, record}, fields, args}) when is_atom(record) do
-    fields = for field <- fields, do: typespec_to_quoted(field)
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    type = {:{}, [], [record | fields]}
-    quote(do: unquote(record)(unquote_splicing(args)) :: unquote(type))
-  end
-
-  def type_to_quoted({name, type, args}) when is_atom(name) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    quote(do: unquote(name)(unquote_splicing(args)) :: unquote(typespec_to_quoted(type)))
-  end
-
-  @doc """
-  Returns all types available from the module's BEAM code.
-
-  The result is returned as a list of tuples where the first
-  element is the type (`:typep`, `:type` and `:opaque`).
-
-  The module must have a corresponding BEAM file which can be
-  located by the runtime system. The types will be in the Erlang
-  Abstract Format.
-  """
-  @spec fetch_types(module | binary) :: {:ok, [tuple]} | :error
-  def fetch_types(module) when is_atom(module) or is_binary(module) do
-    case typespecs_abstract_code(module) do
-      {:ok, abstract_code} ->
-        exported_types = for {:attribute, _, :export_type, types} <- abstract_code, do: types
-        exported_types = List.flatten(exported_types)
-
-        types =
-          for {:attribute, _, kind, {name, _, args} = type} <- abstract_code,
-              kind in [:opaque, :type] do
-            cond do
-              kind == :opaque -> {:opaque, type}
-              {name, length(args)} in exported_types -> {:type, type}
-              true -> {:typep, type}
-            end
-          end
-
-        {:ok, types}
-
-      _ ->
-        :error
-    end
-  end
-
-  @doc """
-  Returns all specs available from the module's BEAM code.
-
-  The result is returned as a list of tuples where the first
-  element is spec name and arity and the second is the spec.
-
-  The module must have a corresponding BEAM file which can be
-  located by the runtime system. The types will be in the Erlang
-  Abstract Format.
-  """
-  @spec fetch_specs(module) :: {:ok, [tuple]} | :error
-  def fetch_specs(module) when is_atom(module) or is_binary(module) do
-    case typespecs_abstract_code(module) do
-      {:ok, abstract_code} ->
-        {:ok, for({:attribute, _, :spec, value} <- abstract_code, do: value)}
-
-      :error ->
-        :error
-    end
-  end
-
-  @doc """
-  Returns all callbacks available from the module's BEAM code.
-
-  The result is returned as a list of tuples where the first
-  element is spec name and arity and the second is the spec.
-
-  The module must have a corresponding BEAM file
-  which can be located by the runtime system. The types will be
-  in the Erlang Abstract Format.
-  """
-  @spec fetch_callbacks(module) :: {:ok, [tuple]} | :error
-  def fetch_callbacks(module) when is_atom(module) or is_binary(module) do
-    case typespecs_abstract_code(module) do
-      {:ok, abstract_code} ->
-        {:ok, for({:attribute, _, :callback, value} <- abstract_code, do: value)}
-
-      :error ->
-        :error
-    end
-  end
-
-  defp typespecs_abstract_code(module) do
-    with {module, binary} <- get_module_and_beam(module),
-         {:ok, {_, [debug_info: {:debug_info_v1, backend, data}]}} <-
-           :beam_lib.chunks(binary, [:debug_info]) do
-      case data do
-        {:elixir_v1, %{}, specs} ->
-          # Fast path to avoid translation to Erlang from Elixir.
-          {:ok, specs}
-
-        _ ->
-          case backend.debug_info(:erlang_v1, module, data, []) do
-            {:ok, abstract_code} -> {:ok, abstract_code}
-            _ -> :error
-          end
-      end
-    else
-      _ -> :error
-    end
-  end
-
-  defp get_module_and_beam(module) when is_atom(module) do
-    case :code.get_object_code(module) do
-      {^module, beam, _filename} -> {module, beam}
-      :error -> :error
-    end
-  end
-
-  defp get_module_and_beam(beam) when is_binary(beam) do
-    case :beam_lib.info(beam) do
-      [_ | _] = info -> {info[:module], beam}
-      _ -> :error
-    end
-  end
-
-  ## To AST conversion
-
-  defp collect_vars({:ann_type, _anno, args}) when is_list(args) do
-    []
-  end
-
-  defp collect_vars({:type, _anno, _kind, args}) when is_list(args) do
-    Enum.flat_map(args, &collect_vars/1)
-  end
-
-  defp collect_vars({:remote_type, _anno, args}) when is_list(args) do
-    Enum.flat_map(args, &collect_vars/1)
-  end
-
-  defp collect_vars({:typed_record_field, _anno, type}) do
-    collect_vars(type)
-  end
-
-  defp collect_vars({:paren_type, _anno, [type]}) do
-    collect_vars(type)
-  end
-
-  defp collect_vars({:var, _anno, var}) do
-    [erl_to_ex_var(var)]
-  end
-
-  defp collect_vars(_) do
-    []
-  end
-
-  defp typespec_to_quoted({:user_type, anno, name, args}) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    {name, meta(anno), args}
-  end
-
-  defp typespec_to_quoted({:type, anno, :tuple, :any}) do
-    {:tuple, meta(anno), []}
-  end
-
-  defp typespec_to_quoted({:type, anno, :tuple, args}) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    {:{}, meta(anno), args}
-  end
-
-  defp typespec_to_quoted({:type, _anno, :list, [{:type, _, :union, unions} = arg]}) do
-    case unpack_typespec_kw(unions, []) do
-      {:ok, ast} -> ast
-      :error -> [typespec_to_quoted(arg)]
-    end
-  end
-
-  defp typespec_to_quoted({:type, anno, :list, []}) do
-    {:list, meta(anno), []}
-  end
-
-  defp typespec_to_quoted({:type, _anno, :list, [arg]}) do
-    [typespec_to_quoted(arg)]
-  end
-
-  defp typespec_to_quoted({:type, anno, :nonempty_list, []}) do
-    [{:..., meta(anno), nil}]
-  end
-
-  defp typespec_to_quoted({:type, anno, :nonempty_list, [arg]}) do
-    [typespec_to_quoted(arg), {:..., meta(anno), nil}]
-  end
-
-  defp typespec_to_quoted({:type, anno, :map, :any}) do
-    {:map, meta(anno), []}
-  end
-
-  defp typespec_to_quoted({:type, anno, :map, fields}) do
-    fields =
-      Enum.map(fields, fn
-        {:type, _, :map_field_assoc, :any} ->
-          {{:optional, [], [{:any, [], []}]}, {:any, [], []}}
-
-        {:type, _, :map_field_exact, [{:atom, _, k}, v]} ->
-          {k, typespec_to_quoted(v)}
-
-        {:type, _, :map_field_exact, [k, v]} ->
-          {{:required, [], [typespec_to_quoted(k)]}, typespec_to_quoted(v)}
-
-        {:type, _, :map_field_assoc, [k, v]} ->
-          {{:optional, [], [typespec_to_quoted(k)]}, typespec_to_quoted(v)}
-      end)
-
-    case List.keytake(fields, :__struct__, 0) do
-      {{:__struct__, struct}, fields_pruned} when is_atom(struct) and struct != nil ->
-        map_pruned = {:%{}, meta(anno), fields_pruned}
-        {:%, meta(anno), [struct, map_pruned]}
-
-      _ ->
-        {:%{}, meta(anno), fields}
-    end
-  end
-
-  defp typespec_to_quoted({:type, anno, :binary, [arg1, arg2]}) do
-    [arg1, arg2] = for arg <- [arg1, arg2], do: typespec_to_quoted(arg)
-    line = meta(anno)[:line]
-
-    case {typespec_to_quoted(arg1), typespec_to_quoted(arg2)} do
-      {arg1, 0} ->
-        quote(line: line, do: <<_::unquote(arg1)>>)
-
-      {0, arg2} ->
-        quote(line: line, do: <<_::_*unquote(arg2)>>)
-
-      {arg1, arg2} ->
-        quote(line: line, do: <<_::unquote(arg1), _::_*unquote(arg2)>>)
-    end
-  end
-
-  defp typespec_to_quoted({:type, anno, :union, args}) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    Enum.reduce(Enum.reverse(args), fn arg, expr -> {:|, meta(anno), [arg, expr]} end)
-  end
-
-  defp typespec_to_quoted({:type, anno, :fun, [{:type, _, :product, args}, result]}) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    [{:->, meta(anno), [args, typespec_to_quoted(result)]}]
-  end
-
-  defp typespec_to_quoted({:type, anno, :fun, [args, result]}) do
-    [{:->, meta(anno), [[typespec_to_quoted(args)], typespec_to_quoted(result)]}]
-  end
-
-  defp typespec_to_quoted({:type, anno, :fun, []}) do
-    typespec_to_quoted({:type, anno, :fun, [{:type, anno, :any}, {:type, anno, :any, []}]})
-  end
-
-  defp typespec_to_quoted({:type, anno, :range, [left, right]}) do
-    {:.., meta(anno), [typespec_to_quoted(left), typespec_to_quoted(right)]}
-  end
-
-  defp typespec_to_quoted({:type, _anno, nil, []}) do
-    []
-  end
-
-  defp typespec_to_quoted({:type, anno, name, args}) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    {name, meta(anno), args}
-  end
-
-  defp typespec_to_quoted({:var, anno, var}) do
-    {erl_to_ex_var(var), meta(anno), nil}
-  end
-
-  defp typespec_to_quoted({:op, anno, op, arg}) do
-    {op, meta(anno), [typespec_to_quoted(arg)]}
-  end
-
-  defp typespec_to_quoted({:remote_type, anno, [mod, name, args]}) do
-    remote_type(anno, mod, name, args)
-  end
-
-  defp typespec_to_quoted({:ann_type, anno, [var, type]}) do
-    {:"::", meta(anno), [typespec_to_quoted(var), typespec_to_quoted(type)]}
-  end
-
-  defp typespec_to_quoted(
-         {:typed_record_field, {:record_field, anno1, {:atom, anno2, name}}, type}
-       ) do
-    typespec_to_quoted({:ann_type, anno1, [{:var, anno2, name}, type]})
-  end
-
-  defp typespec_to_quoted({:type, _, :any}) do
-    quote(do: ...)
-  end
-
-  defp typespec_to_quoted({:paren_type, _, [type]}) do
-    typespec_to_quoted(type)
-  end
-
-  defp typespec_to_quoted({type, _anno, atom}) when is_atom(type) do
-    atom
-  end
-
-  defp typespec_to_quoted(other), do: other
-
-  ## Helpers
-
-  defp remote_type(anno, {:atom, _, :elixir}, {:atom, _, :charlist}, []) do
-    typespec_to_quoted({:type, anno, :charlist, []})
-  end
-
-  defp remote_type(anno, {:atom, _, :elixir}, {:atom, _, :nonempty_charlist}, []) do
-    typespec_to_quoted({:type, anno, :nonempty_charlist, []})
-  end
-
-  defp remote_type(anno, {:atom, _, :elixir}, {:atom, _, :struct}, []) do
-    typespec_to_quoted({:type, anno, :struct, []})
-  end
-
-  defp remote_type(anno, {:atom, _, :elixir}, {:atom, _, :as_boolean}, [arg]) do
-    typespec_to_quoted({:type, anno, :as_boolean, [arg]})
-  end
-
-  defp remote_type(anno, {:atom, _, :elixir}, {:atom, _, :keyword}, args) do
-    typespec_to_quoted({:type, anno, :keyword, args})
-  end
-
-  defp remote_type(anno, mod, name, args) do
-    args = for arg <- args, do: typespec_to_quoted(arg)
-    dot = {:., meta(anno), [typespec_to_quoted(mod), typespec_to_quoted(name)]}
-    {dot, meta(anno), args}
-  end
-
-  defp erl_to_ex_var(var) do
-    case Atom.to_string(var) do
-      <<"_", c::utf8, rest::binary>> ->
-        String.to_atom("_#{String.downcase(<<c::utf8>>)}#{rest}")
-
-      <<c::utf8, rest::binary>> ->
-        String.to_atom("#{String.downcase(<<c::utf8>>)}#{rest}")
-    end
-  end
-
-  defp unpack_typespec_kw([{:type, _, :tuple, [{:atom, _, atom}, type]} | t], acc) do
-    unpack_typespec_kw(t, [{atom, typespec_to_quoted(type)} | acc])
-  end
-
-  defp unpack_typespec_kw([], acc) do
-    {:ok, Enum.reverse(acc)}
-  end
-
-  defp unpack_typespec_kw(_, _acc) do
-    :error
-  end
-
-  defp meta(anno), do: [line: :erl_anno.line(anno)]
-end

lib/elixir/lib/collectable.ex

@@ -17,163 +17,61 @@ defprotocol Collectable do
 
   This design is intentional. `Enumerable` was designed to support infinite
   collections, resources and other structures with fixed shape. For example,
-  it doesn't make sense to insert values into a `Range`, as it has a
-  fixed shape where only the range limits and step are stored.
+  it doesn't make sense to insert values into a range, as it has a fixed
+  shape where just the range limits are stored.
 
   The `Collectable` module was designed to fill the gap left by the
-  `Enumerable` protocol. `Collectable.into/1` can be seen as the opposite of
-  `Enumerable.reduce/3`. If the functions in `Enumerable` are about taking values out,
-  then `Collectable.into/1` is about collecting those values into a structure.
-
-  ## Examples
-
-  To show how to manually use the `Collectable` protocol, let's play with a
-  simplified implementation for `MapSet`.
-
-      iex> {initial_acc, collector_fun} = Collectable.into(MapSet.new())
-      iex> updated_acc = Enum.reduce([1, 2, 3], initial_acc, fn elem, acc ->
-      ...>   collector_fun.(acc, {:cont, elem})
-      ...> end)
-      iex> collector_fun.(updated_acc, :done)
-      #MapSet<[1, 2, 3]>
-
-  To show how the protocol can be implemented, we can again look at the
-  simplified implementation for `MapSet`. In this implementation "collecting" elements
-  simply means inserting them in the set through `MapSet.put/2`.
-
-      defimpl Collectable, for: MapSet do
-        def into(map_set) do
-          collector_fun = fn
-            map_set_acc, {:cont, elem} ->
-              MapSet.put(map_set_acc, elem)
-
-            map_set_acc, :done ->
-              map_set_acc
-
-            _map_set_acc, :halt ->
-              :ok
-          end
-
-          initial_acc = map_set
-
-          {initial_acc, collector_fun}
-        end
-      end
-
-  So now we can call `Enum.into/2`:
-
-      iex> Enum.into([1, 2, 3], MapSet.new())
-      #MapSet<[1, 2, 3]>
-
+  `Enumerable` protocol. `into/1` can be seen as the opposite of
+  `Enumerable.reduce/3`. If `Enumerable` is about taking values out,
+  `Collectable.into/1` is about collecting those values into a structure.
   """
 
   @type command :: {:cont, term} | :done | :halt
 
   @doc """
-  Returns an initial accumulator and a "collector" function.
+  Returns a function that collects values alongside
+  the initial accumulation value.
 
-  Receives a `collectable` which can be used as the initial accumulator that will
-  be passed to the function.
+  The returned function receives a collectable and injects a given
+  value into it for every `{:cont, term}` instruction.
 
-  The collector function receives a term and a command and injects the term into
-  the collectable accumulator on every `{:cont, term}` command.
+  `:done` is passed when no further values will be injected, useful
+  for closing resources and normalizing values. A collectable must
+  be returned on `:done`.
 
-  `:done` is passed as a command when no further values will be injected. This
-  is useful when there's a need to close resources or normalizing values. A
-  collectable must be returned when the command is `:done`.
-
-  If injection is suddenly interrupted, `:halt` is passed and the function
-  can return any value as it won't be used.
-
-  For examples on how to use the `Collectable` protocol and `into/1` see the
-  module documentation.
+  If injection is suddenly interrupted, `:halt` is passed and it can
+  return any value, as it won't be used.
   """
-  @spec into(t) :: {initial_acc :: term, collector :: (term, command -> t | term)}
+  @spec into(t) :: {term, (term, command -> t | term)}
   def into(collectable)
 end
 
 defimpl Collectable, for: List do
-  def into(list) do
-    # TODO: Change the behaviour so the into always comes last on Elixir v2.0
-    if list != [] do
-      IO.warn(
-        "the Collectable protocol is deprecated for non-empty lists. The behaviour of " <>
-          "Enum.into/2 and \"for\" comprehensions with an :into option is incorrect " <>
-          "when collecting into non-empty lists. If you're collecting into a non-empty keyword " <>
-          "list, consider using Keyword.merge/2 instead. If you're collecting into a non-empty " <>
-          "list, consider concatenating the two lists with the ++ operator."
-      )
-    end
-
-    fun = fn
-      list_acc, {:cont, elem} ->
-        [elem | list_acc]
-
-      list_acc, :done ->
-        list ++ :lists.reverse(list_acc)
-
-      _list_acc, :halt ->
-        :ok
-    end
-
-    {[], fun}
+  def into(original) do
+    {[], fn
+      list, {:cont, x} -> [x | list]
+      list, :done -> original ++ :lists.reverse(list)
+      _, :halt -> :ok
+    end}
   end
 end
 
 defimpl Collectable, for: BitString do
-  def into(binary) when is_binary(binary) do
-    fun = fn
-      acc, {:cont, x} when is_binary(x) and is_list(acc) ->
-        [acc | x]
-
-      acc, {:cont, x} when is_bitstring(x) and is_bitstring(acc) ->
-        <<acc::bitstring, x::bitstring>>
-
-      acc, {:cont, x} when is_bitstring(x) ->
-        <<IO.iodata_to_binary(acc)::bitstring, x::bitstring>>
-
-      acc, :done when is_bitstring(acc) ->
-        acc
-
-      acc, :done ->
-        IO.iodata_to_binary(acc)
-
-      __acc, :halt ->
-        :ok
-    end
-
-    {[binary], fun}
-  end
-
-  def into(bitstring) do
-    fun = fn
-      acc, {:cont, x} when is_bitstring(x) ->
-        <<acc::bitstring, x::bitstring>>
-
-      acc, :done ->
-        acc
-
-      _acc, :halt ->
-        :ok
-    end
-
-    {bitstring, fun}
+  def into(original) do
+    {original, fn
+      acc, {:cont, x} when is_bitstring(x) -> [acc | x]
+      acc, :done -> IO.iodata_to_binary(acc)
+      _, :halt -> :ok
+    end}
   end
 end
 
 defimpl Collectable, for: Map do
-  def into(map) do
-    fun = fn
-      map_acc, {:cont, {key, value}} ->
-        Map.put(map_acc, key, value)
-
-      map_acc, :done ->
-        map_acc
-
-      _map_acc, :halt ->
-        :ok
-    end
-
-    {map, fun}
+  def into(original) do
+    {original, fn
+      map, {:cont, {k, v}} -> :maps.put(k, v, map)
+      map, :done -> map
+      _, :halt -> :ok
+    end}
   end
 end

lib/elixir/lib/config.ex

@@ -1,333 +0,0 @@
-defmodule Config do
-  @moduledoc ~S"""
-  A simple keyword-based configuration API.
-
-  ## Example
-
-  This module is most commonly used to define application configuration,
-  typically in `config/config.exs`:
-
-      import Config
-
-      config :some_app,
-        key1: "value1",
-        key2: "value2"
-
-      import_config "#{config_env()}.exs"
-
-  `import Config` will import the functions `config/2`, `config/3`
-  `config_env/0`, `config_target/0`, and `import_config/1`
-  to help you manage your configuration.
-
-  `config/2` and `config/3` are used to define key-value configuration
-  for a given application. Once Mix starts, it will automatically
-  evaluate the configuration file and persist the configuration above
-  into `:some_app`'s application environment, which can be accessed in
-  as follows:
-
-      "value1" = Application.fetch_env!(:some_app, :key1)
-
-  Finally, the line `import_config "#{config_env()}.exs"` will import
-  other config files based on the current configuration environment,
-  such as `config/dev.exs` and `config/test.exs`.
-
-  `Config` also provides a low-level API for evaluating and reading
-  configuration, under the `Config.Reader` module.
-
-  **Important:** if you are writing a library to be used by other developers,
-  it is generally recommended to avoid the application environment, as the
-  application environment is effectively a global storage. Also note that
-  the `config/config.exs` of a library is not evaluated when the library is
-  used as a dependency, as configuration is always meant to configure the
-  current project. For more information, read our [library guidelines](library-guidelines.md).
-
-  ## Migrating from `use Mix.Config`
-
-  The `Config` module in Elixir was introduced in v1.9 as a replacement to
-  `Mix.Config`, which was specific to Mix and has been deprecated.
-
-  You can leverage `Config` instead of `Mix.Config` in three steps. The first
-  step is to replace `use Mix.Config` at the top of your config files by
-  `import Config`.
-
-  The second is to make sure your `import_config/1` calls do not have a
-  wildcard character. If so, you need to perform the wildcard lookup
-  manually. For example, if you did:
-
-      import_config "../apps/*/config/config.exs"
-
-  It has to be replaced by:
-
-      for config <- "../apps/*/config/config.exs" |> Path.expand(__DIR__) |> Path.wildcard() do
-        import_config config
-      end
-
-  The last step is to replace all `Mix.env()` calls by `config_env()`.
-
-  ## config/runtime.exs
-
-  For runtime configuration, you can use the `config/runtime.exs` file.
-  It is executed right before applications start in both Mix and releases
-  (assembled with `mix release`).
-  """
-
-  @opts_key {__MODULE__, :opts}
-  @config_key {__MODULE__, :config}
-  @imports_key {__MODULE__, :imports}
-
-  defp get_opts!(), do: Process.get(@opts_key) || raise_improper_use!()
-  defp put_opts(value), do: Process.put(@opts_key, value)
-  defp delete_opts(), do: Process.delete(@opts_key)
-
-  defp get_config!(), do: Process.get(@config_key) || raise_improper_use!()
-  defp put_config(value), do: Process.put(@config_key, value)
-  defp delete_config(), do: Process.delete(@config_key)
-
-  defp get_imports!(), do: Process.get(@imports_key) || raise_improper_use!()
-  defp put_imports(value), do: Process.put(@imports_key, value)
-  defp delete_imports(), do: Process.delete(@imports_key)
-
-  defp raise_improper_use!() do
-    raise "could not set configuration via Config. " <>
-            "This usually means you are trying to execute a configuration file " <>
-            "directly, instead of reading it with Config.Reader"
-  end
-
-  @doc """
-  Configures the given `root_key`.
-
-  Keyword lists are always deep-merged.
-
-  ## Examples
-
-  The given `opts` are merged into the existing configuration
-  for the given `root_key`. Conflicting keys are overridden by the
-  ones specified in `opts`, unless they are keywords, which are
-  deep merged recursively. For example, the application configuration
-  below
-
-      config :logger,
-        level: :warn,
-        backends: [:console]
-
-      config :logger,
-        level: :info,
-        truncate: 1024
-
-  will have a final configuration for `:logger` of:
-
-      [level: :info, backends: [:console], truncate: 1024]
-
-  """
-  @doc since: "1.9.0"
-  def config(root_key, opts) when is_atom(root_key) and is_list(opts) do
-    unless Keyword.keyword?(opts) do
-      raise ArgumentError, "config/2 expected a keyword list, got: #{inspect(opts)}"
-    end
-
-    get_config!()
-    |> __merge__([{root_key, opts}])
-    |> put_config()
-  end
-
-  @doc """
-  Configures the given `key` for the given `root_key`.
-
-  Keyword lists are always deep merged.
-
-  ## Examples
-
-  The given `opts` are merged into the existing values for `key`
-  in the given `root_key`. Conflicting keys are overridden by the
-  ones specified in `opts`, unless they are keywords, which are
-  deep merged recursively. For example, the application configuration
-  below
-
-      config :ecto, Repo,
-        log_level: :warn,
-        adapter: Ecto.Adapters.Postgres
-
-      config :ecto, Repo,
-        log_level: :info,
-        pool_size: 10
-
-  will have a final value of the configuration for the `Repo`
-  key in the `:ecto` application of:
-
-      [log_level: :info, pool_size: 10, adapter: Ecto.Adapters.Postgres]
-
-  """
-  @doc since: "1.9.0"
-  def config(root_key, key, opts) when is_atom(root_key) and is_atom(key) do
-    get_config!()
-    |> __merge__([{root_key, [{key, opts}]}])
-    |> put_config()
-  end
-
-  @doc """
-  Returns the environment this configuration file is executed on.
-
-  In Mix projects this function returns the environment this configuration
-  file is executed on. In releases, the environment when `mix release` ran.
-
-  This is most often used to execute conditional code:
-
-      if config_env() == :prod do
-        config :my_app, :debug, false
-      end
-
-  """
-  @doc since: "1.11.0"
-  defmacro config_env() do
-    quote do
-      Config.__env__!()
-    end
-  end
-
-  @doc false
-  @spec __env__!() :: atom()
-  def __env__!() do
-    elem(get_opts!(), 0) || raise "no :env key was given to this configuration file"
-  end
-
-  @doc """
-  Returns the target this configuration file is executed on.
-
-  This is most often used to execute conditional code:
-
-      if config_target() == :host do
-        config :my_app, :debug, false
-      end
-
-  """
-  @doc since: "1.11.0"
-  defmacro config_target() do
-    quote do
-      Config.__target__!()
-    end
-  end
-
-  @doc false
-  @spec __target__!() :: atom()
-  def __target__!() do
-    elem(get_opts!(), 1) || raise "no :target key was given to this configuration file"
-  end
-
-  @doc ~S"""
-  Imports configuration from the given file.
-
-  In case the file doesn't exist, an error is raised.
-
-  If file is a relative, it will be expanded relatively to the
-  directory the current configuration file is in.
-
-  ## Examples
-
-  This is often used to emulate configuration across environments:
-
-      import_config "#{config_env()}.exs"
-
-  Note, however, some configuration files, such as `config/runtime.exs`
-  does not support imports, as they are meant to be copied across
-  systems.
-  """
-  @doc since: "1.9.0"
-  defmacro import_config(file) do
-    quote do
-      Config.__import__!(Path.expand(unquote(file), __DIR__))
-      :ok
-    end
-  end
-
-  @doc false
-  @spec __import__!(Path.t()) :: {term, Code.binding()}
-  def __import__!(file) when is_binary(file) do
-    import_config!(file, File.read!(file), true)
-  end
-
-  @doc false
-  @spec __eval__!(Path.t(), binary(), keyword) :: {keyword, [Path.t()] | :disabled}
-  def __eval__!(file, content, opts \\ []) when is_binary(file) and is_list(opts) do
-    env = Keyword.get(opts, :env)
-    target = Keyword.get(opts, :target)
-    imports = Keyword.get(opts, :imports, [])
-
-    previous_opts = put_opts({env, target})
-    previous_config = put_config([])
-    previous_imports = put_imports(imports)
-
-    try do
-      {eval_config, _} = import_config!(file, content, false)
-
-      case get_config!() do
-        [] when is_list(eval_config) ->
-          {validate!(eval_config, file), get_imports!()}
-
-        pdict_config ->
-          {pdict_config, get_imports!()}
-      end
-    after
-      if previous_opts, do: put_opts(previous_opts), else: delete_opts()
-      if previous_config, do: put_config(previous_config), else: delete_config()
-      if previous_imports, do: put_imports(previous_imports), else: delete_imports()
-    end
-  end
-
-  defp import_config!(file, contents, raise_when_disabled?) do
-    current_imports = get_imports!()
-
-    cond do
-      current_imports == :disabled ->
-        if raise_when_disabled? do
-          raise "import_config/1 is not enabled for this configuration file. " <>
-                  "Some configuration files do not allow importing other files " <>
-                  "as they are often copied to external systems"
-        end
-
-      file in current_imports ->
-        raise ArgumentError,
-              "attempting to load configuration #{Path.relative_to_cwd(file)} recursively"
-
-      true ->
-        put_imports([file | current_imports])
-        :ok
-    end
-
-    # TODO: Emit a warning if Mix.env() is found in said files in Elixir v1.15.
-    # Note this won't be a deprecation warning as it will always be emitted.
-    Code.eval_string(contents, [], file: file)
-  end
-
-  @doc false
-  def __merge__(config1, config2) when is_list(config1) and is_list(config2) do
-    Keyword.merge(config1, config2, fn _, app1, app2 ->
-      Keyword.merge(app1, app2, &deep_merge/3)
-    end)
-  end
-
-  defp deep_merge(_key, value1, value2) do
-    if Keyword.keyword?(value1) and Keyword.keyword?(value2) do
-      Keyword.merge(value1, value2, &deep_merge/3)
-    else
-      value2
-    end
-  end
-
-  defp validate!(config, file) do
-    Enum.all?(config, fn
-      {app, value} when is_atom(app) ->
-        if Keyword.keyword?(value) do
-          true
-        else
-          raise ArgumentError,
-                "expected config for app #{inspect(app)} in #{Path.relative_to_cwd(file)} " <>
-                  "to return keyword list, got: #{inspect(value)}"
-        end
-
-      _ ->
-        false
-    end)
-
-    config
-  end
-end

lib/elixir/lib/config/provider.ex

@@ -1,416 +0,0 @@
-defmodule Config.Provider do
-  @moduledoc """
-  Specifies a provider API that loads configuration during boot.
-
-  Config providers are typically used during releases to load
-  external configuration while the system boots. This is done
-  by starting the VM with the minimum amount of applications
-  running, then invoking all of the providers, and then
-  restarting the system. This requires a mutable configuration
-  file on disk, as the results of the providers are written to
-  the file system. For more information on runtime configuration,
-  see `mix release`.
-
-  ## Multiple config files
-
-  One common use of config providers is to specify multiple
-  configuration files in a release. Elixir ships with one provider,
-  called `Config.Reader`, which is capable of handling Elixir's
-  built-in config files.
-
-  For example, imagine you want to list some basic configuration
-  on Mix's built-in `config/runtime.exs` file, but you also want
-  to support additional configuration files. To do so, you can add
-  this inside the `def project` portion of  your `mix.exs`:
-
-      releases: [
-        demo: [
-          config_providers: [
-            {Config.Reader, {:system, "RELEASE_ROOT", "/extra_config.exs"}}
-          ]
-        ]
-      ]
-
-  You can place this `extra_config.exs` file in your release in
-  multiple ways:
-
-    1. If it is available on the host when assembling the release,
-      you can place it on "rel/overlays/extra_config.exs" and it
-      will be automatically copied to the release root
-
-    2. If it is available on the target during deployment, you can
-      simply copy it to the release root as a step in your deployment
-
-  Now once the system boots, it will load both `config/runtime.exs`
-  and `extra_config.exs` early in the boot process. You can learn
-  more options on `Config.Reader`.
-
-  ## Custom config provider
-
-  You can also implement custom config providers, similar to how
-  `Config.Reader` works. For example, imagine you need to load
-  some configuration from a JSON file and load that into the system.
-  Said configuration provider would look like:
-
-      defmodule JSONConfigProvider do
-        @behaviour Config.Provider
-
-        # Let's pass the path to the JSON file as config
-        @impl true
-        def init(path) when is_binary(path), do: path
-
-        @impl true
-        def load(config, path) do
-          # We need to start any app we may depend on.
-          {:ok, _} = Application.ensure_all_started(:jason)
-
-          json = path |> File.read!() |> Jason.decode!()
-
-          Config.Reader.merge(
-            config,
-            my_app: [
-              some_value: json["my_app_some_value"],
-              another_value: json["my_app_another_value"],
-            ]
-          )
-        end
-      end
-
-  Then, when specifying your release, you can specify the provider in
-  the release configuration:
-
-      releases: [
-        demo: [
-          config_providers: [
-            {JSONConfigProvider, "/etc/config.json"}
-          ]
-        ]
-      ]
-
-  """
-
-  @type config :: keyword
-  @type state :: term
-
-  @typedoc """
-  A path pointing to a configuration file.
-
-  Since configuration files are often accessed on target machines,
-  it can be expressed either as:
-
-    * a binary representing an absolute path
-
-    * a `{:system, system_var, path}` tuple where the config is the
-      concatenation of the environment variable `system_var` with
-      the given `path`
-
-  """
-  @type config_path :: {:system, binary(), binary()} | binary()
-
-  @doc """
-  Invoked when initializing a config provider.
-
-  A config provider is typically initialized on the machine
-  where the system is assembled and not on the target machine.
-  The `c:init/1` callback is useful to verify the arguments
-  given to the provider and prepare the state that will be
-  given to `c:load/2`.
-
-  Furthermore, because the state returned by `c:init/1` can
-  be written to text-based config files, it should be
-  restricted only to simple data types, such as integers,
-  strings, atoms, tuples, maps, and lists. Entries such as
-  PIDs, references, and functions cannot be serialized.
-  """
-  @callback init(term) :: state
-
-  @doc """
-  Loads configuration (typically during system boot).
-
-  It receives the current `config` and the `state` returned by
-  `c:init/1`. Then, you typically read the extra configuration
-  from an external source and merge it into the received `config`.
-  Merging should be done with `Config.Reader.merge/2`, as it
-  performs deep merge. It should return the updated config.
-
-  Note that `c:load/2` is typically invoked very early in the
-  boot process, therefore if you need to use an application
-  in the provider, it is your responsibility to start it.
-  """
-  @callback load(config, state) :: config
-
-  @doc false
-  defstruct [
-    :providers,
-    :config_path,
-    extra_config: [],
-    prune_runtime_sys_config_after_boot: false,
-    reboot_system_after_config: false,
-    validate_compile_env: false
-  ]
-
-  @reserved_apps [:kernel, :stdlib]
-
-  @doc """
-  Validates a `t:config_path/0`.
-  """
-  @doc since: "1.9.0"
-  @spec validate_config_path!(config_path) :: :ok
-  def validate_config_path!({:system, name, path})
-      when is_binary(name) and is_binary(path),
-      do: :ok
-
-  def validate_config_path!(path) do
-    if is_binary(path) and Path.type(path) != :relative do
-      :ok
-    else
-      raise ArgumentError, """
-      expected configuration path to be:
-
-        * a binary representing an absolute path
-        * a tuple {:system, system_var, path} where the config is the \
-      concatenation of the `system_var` with the given `path`
-
-      Got: #{inspect(path)}
-      """
-    end
-  end
-
-  @doc """
-  Resolves a `t:config_path/0` to an actual path.
-  """
-  @doc since: "1.9.0"
-  @spec resolve_config_path!(config_path) :: binary
-  def resolve_config_path!(path) when is_binary(path), do: path
-  def resolve_config_path!({:system, name, path}), do: System.fetch_env!(name) <> path
-
-  # Private keys
-  @init_key :config_provider_init
-  @booted_key :config_provider_booted
-
-  # Public keys
-  @reboot_mode_key :config_provider_reboot_mode
-
-  @doc false
-  def init(providers, config_path, opts \\ []) when is_list(providers) and is_list(opts) do
-    validate_config_path!(config_path)
-    providers = for {provider, init} <- providers, do: {provider, provider.init(init)}
-    init = struct!(%Config.Provider{config_path: config_path, providers: providers}, opts)
-    [elixir: [{@init_key, init}]]
-  end
-
-  @doc false
-  def boot(reboot_fun \\ &restart_and_sleep/0) do
-    # The config provider typically runs very early in the
-    # release process, so we need to make sure Elixir is started
-    # before we go around running Elixir code.
-    {:ok, _} = :application.ensure_all_started(:elixir)
-
-    case Application.fetch_env(:elixir, @booted_key) do
-      {:ok, {:booted, path}} ->
-        path && File.rm(path)
-
-        with {:ok, %Config.Provider{} = provider} <- Application.fetch_env(:elixir, @init_key) do
-          maybe_validate_compile_env(provider)
-        end
-
-        :booted
-
-      _ ->
-        case Application.fetch_env(:elixir, @init_key) do
-          {:ok, %Config.Provider{} = provider} ->
-            path = resolve_config_path!(provider.config_path)
-            reboot_config = [elixir: [{@booted_key, booted_value(provider, path)}]]
-            boot_providers(path, provider, reboot_config, reboot_fun)
-
-          _ ->
-            :skip
-        end
-    end
-  end
-
-  defp boot_providers(path, provider, reboot_config, reboot_fun) do
-    original_config = read_config!(path)
-
-    config =
-      original_config
-      |> Config.__merge__(provider.extra_config)
-      |> run_providers(provider)
-
-    if provider.reboot_system_after_config do
-      config
-      |> Config.__merge__(reboot_config)
-      |> write_config!(path)
-
-      reboot_fun.()
-    else
-      for app <- @reserved_apps, config[app] != original_config[app] do
-        abort("""
-        Cannot configure #{inspect(app)} because :reboot_system_after_config has been set \
-        to false and #{inspect(app)} has already been loaded, meaning any further \
-        configuration won't have an effect.
-
-        The configuration for #{inspect(app)} before config providers was:
-
-        #{inspect(original_config[app])}
-
-        The configuration for #{inspect(app)} after config providers was:
-
-        #{inspect(config[app])}
-        """)
-      end
-
-      _ = Application.put_all_env(config, persistent: true)
-      maybe_validate_compile_env(provider)
-      :ok
-    end
-  end
-
-  defp maybe_validate_compile_env(provider) do
-    with [_ | _] = compile_env <- provider.validate_compile_env do
-      validate_compile_env(compile_env)
-    end
-  end
-
-  @doc false
-  def validate_compile_env(compile_env, ensure_loaded? \\ true) do
-    for {app, [key | path], compile_return} <- compile_env,
-        ensure_app_loaded?(app, ensure_loaded?) do
-      try do
-        traverse_env(Application.fetch_env(app, key), path)
-      rescue
-        e ->
-          abort("""
-          application #{inspect(app)} failed reading its compile environment #{path(key, path)}:
-
-          #{Exception.format(:error, e, __STACKTRACE__)}
-
-          Expected it to match the compile time value of #{return_to_text(compile_return)}.
-
-          #{compile_env_tips(app)}
-          """)
-      else
-        ^compile_return ->
-          :ok
-
-        runtime_return ->
-          abort("""
-          the application #{inspect(app)} has a different value set #{path(key, path)} \
-          during runtime compared to compile time. Since this application environment entry was \
-          marked as compile time, this difference can lead to different behaviour than expected:
-
-            * Compile time value #{return_to_text(compile_return)}
-            * Runtime value #{return_to_text(runtime_return)}
-
-          #{compile_env_tips(app)}
-          """)
-      end
-    end
-
-    :ok
-  end
-
-  defp ensure_app_loaded?(app, true), do: Application.ensure_loaded(app) == :ok
-  defp ensure_app_loaded?(app, false), do: Application.spec(app, :vsn) != nil
-
-  defp path(key, []), do: "for key #{inspect(key)}"
-  defp path(key, path), do: "for path #{inspect(path)} inside key #{inspect(key)}"
-
-  defp compile_env_tips(app),
-    do: """
-    To fix this error, you might:
-
-      * Make the runtime value match the compile time one
-
-      * Recompile your project. If the misconfigured application is a dependency, \
-    you may need to run "mix deps.compile #{app} --force"
-
-      * Alternatively, you can disable this check. If you are using releases, you can \
-    set :validate_compile_env to false in your release configuration. If you are \
-    using Mix to start your system, you can pass the --no-validate-compile-env flag
-    """
-
-  defp return_to_text({:ok, value}), do: "was set to: #{inspect(value)}"
-  defp return_to_text(:error), do: "was not set"
-
-  defp traverse_env(return, []), do: return
-  defp traverse_env(:error, _paths), do: :error
-  defp traverse_env({:ok, value}, [key | keys]), do: traverse_env(Access.fetch(value, key), keys)
-
-  @compile {:no_warn_undefined, {:init, :restart, 1}}
-  defp restart_and_sleep() do
-    mode = Application.get_env(:elixir, @reboot_mode_key)
-
-    # TODO: Remove otp_release check once we require Erlang/OTP 23+
-    if :erlang.system_info(:otp_release) >= '23' and mode in [:embedded, :interactive] do
-      :init.restart(mode: mode)
-    else
-      :init.restart()
-    end
-
-    Process.sleep(:infinity)
-  end
-
-  defp booted_value(%{prune_runtime_sys_config_after_boot: true}, path), do: {:booted, path}
-  defp booted_value(%{prune_runtime_sys_config_after_boot: false}, _path), do: {:booted, nil}
-
-  defp read_config!(path) do
-    case :file.consult(path) do
-      {:ok, [inner]} ->
-        inner
-
-      {:error, reason} ->
-        bad_path_abort(
-          "Could not read runtime configuration due to reason: #{inspect(reason)}",
-          path
-        )
-    end
-  end
-
-  defp run_providers(config, %{providers: providers}) do
-    Enum.reduce(providers, config, fn {provider, state}, acc ->
-      try do
-        provider.load(acc, state)
-      catch
-        kind, error ->
-          IO.puts(:stderr, "ERROR! Config provider #{inspect(provider)} failed with:")
-          IO.puts(:stderr, Exception.format(kind, error, __STACKTRACE__))
-          :erlang.raise(kind, error, __STACKTRACE__)
-      else
-        term when is_list(term) ->
-          term
-
-        term ->
-          abort("Expected provider #{inspect(provider)} to return a list, got: #{inspect(term)}")
-      end
-    end)
-  end
-
-  defp write_config!(config, path) do
-    contents = :io_lib.format("%% coding: utf-8~n~tw.~n", [config])
-
-    case File.write(path, IO.chardata_to_string(contents)) do
-      :ok ->
-        :ok
-
-      {:error, reason} ->
-        bad_path_abort(
-          "Could not write runtime configuration due to reason: #{inspect(reason)}",
-          path
-        )
-    end
-  end
-
-  defp bad_path_abort(msg, path) do
-    abort(
-      msg <>
-        ". Please make sure #{inspect(path)} is writable and accessible " <>
-        "or choose a different path"
-    )
-  end
-
-  defp abort(msg) do
-    IO.puts(:stderr, "ERROR! " <> msg)
-    :erlang.raise(:error, "aborting boot", [{Config.Provider, :boot, 2, []}])
-  end
-end

lib/elixir/lib/config/reader.ex

@@ -1,138 +0,0 @@
-defmodule Config.Reader do
-  @moduledoc """
-  API for reading config files defined with `Config`.
-
-  ## As a provider
-
-  `Config.Reader` can also be used as a `Config.Provider`. A config
-  provider is used during releases to customize how applications are
-  configured. When used as a provider, it expects a single argument:
-  the configuration path (as outlined in `t:Config.Provider.config_path/0`)
-  for the file to be read and loaded during the system boot.
-
-  For example, if you expect the target system to have a config file
-  in an absolute path, you can add this inside the `def project` portion
-  of  your `mix.exs`:
-
-      releases: [
-        demo: [
-          config_providers: [
-            {Config.Reader, "/etc/config.exs"}
-          ]
-        ]
-      ]
-
-  Or if you want to read a custom path inside the release:
-
-      config_providers: [{Config.Reader, {:system, "RELEASE_ROOT", "/config.exs"}}]
-
-  You can also pass a keyword list of options to the reader,
-  where the `:path` is a required key:
-
-      config_providers: [
-        {Config.Reader,
-         path: "/etc/config.exs",
-         env: :prod,
-         imports: :disabled}
-      ]
-
-  Remember Mix already loads `config/runtime.exs` by default.
-  For more examples and scenarios, see the `Config.Providers` module.
-  """
-
-  @behaviour Config.Provider
-
-  @impl true
-  def init(opts) when is_list(opts) do
-    {path, opts} = Keyword.pop!(opts, :path)
-    Config.Provider.validate_config_path!(path)
-    {path, opts}
-  end
-
-  def init(path) do
-    init(path: path)
-  end
-
-  @impl true
-  def load(config, {path, opts}) do
-    merge(config, path |> Config.Provider.resolve_config_path!() |> read!(opts))
-  end
-
-  @doc """
-  Evaluates the configuration `contents` for the given `file`.
-
-  Accepts the same options as `read!/2`.
-  """
-  @doc since: "1.11.0"
-  @spec eval!(Path.t(), binary, keyword) :: keyword
-  def eval!(file, contents, opts \\ [])
-      when is_binary(file) and is_binary(contents) and is_list(opts) do
-    Config.__eval__!(Path.expand(file), contents, opts) |> elem(0)
-  end
-
-  @doc """
-  Reads the configuration file.
-
-  ## Options
-
-    * `:imports` - a list of already imported paths or `:disabled`
-      to disable imports
-
-    * `:env` - the environment the configuration file runs on.
-      See `Config.config_env/0` for sample usage
-
-    * `:target` - the target the configuration file runs on.
-      See `Config.config_target/0` for sample usage
-
-  """
-  @doc since: "1.9.0"
-  @spec read!(Path.t(), keyword) :: keyword
-  def read!(file, opts \\ []) when is_binary(file) and is_list(opts) do
-    file = Path.expand(file)
-    Config.__eval__!(file, File.read!(file), opts) |> elem(0)
-  end
-
-  @doc """
-  Reads the given configuration file and returns the configuration
-  with its imports.
-
-  Accepts the same options as `read!/2`. Although note the `:imports`
-  option cannot be disabled in `read_imports!/2`.
-  """
-  @doc since: "1.9.0"
-  @spec read_imports!(Path.t(), keyword) :: {keyword, [Path.t()]}
-  def read_imports!(file, opts \\ []) when is_binary(file) and is_list(opts) do
-    if opts[:imports] == :disabled do
-      raise ArgumentError, ":imports must be a list of paths"
-    end
-
-    file = Path.expand(file)
-    Config.__eval__!(file, File.read!(file), opts)
-  end
-
-  @doc """
-  Merges two configurations.
-
-  The configurations are merged together with the values in
-  the second one having higher preference than the first in
-  case of conflicts. In case both values are set to keyword
-  lists, it deep merges them.
-
-  ## Examples
-
-      iex> Config.Reader.merge([app: [k: :v1]], [app: [k: :v2]])
-      [app: [k: :v2]]
-
-      iex> Config.Reader.merge([app: [k: [v1: 1, v2: 2]]], [app: [k: [v2: :a, v3: :b]]])
-      [app: [k: [v1: 1, v2: :a, v3: :b]]]
-
-      iex> Config.Reader.merge([app1: []], [app2: []])
-      [app1: [], app2: []]
-
-  """
-  @doc since: "1.9.0"
-  @spec merge(keyword, keyword) :: keyword
-  def merge(config1, config2) when is_list(config1) and is_list(config2) do
-    Config.__merge__(config1, config2)
-  end
-end

lib/elixir/lib/dict.ex

@@ -1,6 +1,6 @@
 defmodule Dict do
   @moduledoc ~S"""
-  Generic API for dictionaries.
+  WARNING: this module is deprecated.
 
   If you need a general dictionary, use the `Map` module.
   If you need to manipulate keyword lists, use `Keyword`.
@@ -9,27 +9,19 @@ defmodule Dict do
   `new` function in the respective modules.
   """
 
-  @moduledoc deprecated: "Use Map or Keyword modules instead"
-
   @type key :: any
   @type value :: any
   @type t :: list | map
 
-  message =
-    "Use the Map module for working with maps or the Keyword module for working with keyword lists"
-
+  # TODO: Deprecate every function by 1.4
   defmacro __using__(_) do
     # Use this import to guarantee proper code expansion
     import Kernel, except: [size: 1]
 
-    if __CALLER__.module != HashDict do
-      IO.warn("use Dict is deprecated. " <> unquote(message), Macro.Env.stacktrace(__CALLER__))
-    end
+    %{file: file, line: line} = __CALLER__
+    :elixir_errors.warn(line, file, "the Dict module is deprecated")
 
     quote do
-      message = "Use maps and the Map module instead"
-
-      @deprecated message
       def get(dict, key, default \\ nil) do
         case fetch(dict, key) do
           {:ok, value} -> value
@@ -37,7 +29,6 @@ defmodule Dict do
         end
       end
 
-      @deprecated message
       def get_lazy(dict, key, fun) when is_function(fun, 0) do
         case fetch(dict, key) do
           {:ok, value} -> value
@@ -45,14 +36,12 @@ defmodule Dict do
         end
       end
 
-      @deprecated message
       def get_and_update(dict, key, fun) do
         current_value = get(dict, key)
         {get, new_value} = fun.(current_value)
         {get, put(dict, key, new_value)}
       end
 
-      @deprecated message
       def fetch!(dict, key) do
         case fetch(dict, key) do
           {:ok, value} -> value
@@ -60,33 +49,28 @@ defmodule Dict do
         end
       end
 
-      @deprecated message
       def has_key?(dict, key) do
-        match?({:ok, _}, fetch(dict, key))
+        match? {:ok, _}, fetch(dict, key)
       end
 
-      @deprecated message
       def put_new(dict, key, value) do
         case has_key?(dict, key) do
-          true -> dict
+          true  -> dict
           false -> put(dict, key, value)
         end
       end
 
-      @deprecated message
       def put_new_lazy(dict, key, fun) when is_function(fun, 0) do
         case has_key?(dict, key) do
-          true -> dict
+          true  -> dict
           false -> put(dict, key, fun.())
         end
       end
 
-      @deprecated message
       def drop(dict, keys) do
         Enum.reduce(keys, dict, &delete(&2, &1))
       end
 
-      @deprecated message
       def take(dict, keys) do
         Enum.reduce(keys, new(), fn key, acc ->
           case fetch(dict, key) do
@@ -96,49 +80,41 @@ defmodule Dict do
         end)
       end
 
-      @deprecated message
       def to_list(dict) do
-        reduce(dict, {:cont, []}, fn kv, acc -> {:cont, [kv | acc]} end)
-        |> elem(1)
-        |> :lists.reverse()
+        reduce(dict, {:cont, []}, fn
+          kv, acc -> {:cont, [kv | acc]}
+        end) |> elem(1) |> :lists.reverse
       end
 
-      @deprecated message
       def keys(dict) do
-        reduce(dict, {:cont, []}, fn {k, _}, acc -> {:cont, [k | acc]} end)
-        |> elem(1)
-        |> :lists.reverse()
+        reduce(dict, {:cont, []}, fn
+          {k, _}, acc -> {:cont, [k | acc]}
+        end) |> elem(1) |> :lists.reverse
       end
 
-      @deprecated message
       def values(dict) do
-        reduce(dict, {:cont, []}, fn {_, v}, acc -> {:cont, [v | acc]} end)
-        |> elem(1)
-        |> :lists.reverse()
+        reduce(dict, {:cont, []}, fn
+          {_, v}, acc -> {:cont, [v | acc]}
+        end) |> elem(1) |> :lists.reverse
       end
 
-      @deprecated message
       def equal?(dict1, dict2) do
         # Use this import to avoid conflicts in the user code
         import Kernel, except: [size: 1]
 
         case size(dict1) == size(dict2) do
-          false ->
-            false
-
-          true ->
-            reduce(dict1, {:cont, true}, fn {k, v}, _acc ->
+          false -> false
+          true  ->
+            reduce(dict1, {:cont, true}, fn({k, v}, _acc) ->
               case fetch(dict2, k) do
                 {:ok, ^v} -> {:cont, true}
                 _ -> {:halt, false}
               end
-            end)
-            |> elem(1)
+            end) |> elem(1)
         end
       end
 
-      @deprecated message
-      def merge(dict1, dict2, fun \\ fn _k, _v1, v2 -> v2 end) do
+      def merge(dict1, dict2, fun \\ fn(_k, _v1, v2) -> v2 end) do
         # Use this import to avoid conflicts in the user code
         import Kernel, except: [size: 1]
 
@@ -150,182 +126,144 @@ defmodule Dict do
           reduce(dict2, {:cont, dict1}, fn {k, v2}, acc ->
             {:cont, update(acc, k, v2, &fun.(k, &1, v2))}
           end)
-        end
-        |> elem(1)
+        end |> elem(1)
       end
 
-      @deprecated message
-      def update(dict, key, default, fun) do
+      def update(dict, key, initial, fun) do
         case fetch(dict, key) do
           {:ok, value} ->
             put(dict, key, fun.(value))
-
           :error ->
-            put(dict, key, default)
+            put(dict, key, initial)
         end
       end
 
-      @deprecated message
       def update!(dict, key, fun) do
         case fetch(dict, key) do
           {:ok, value} ->
             put(dict, key, fun.(value))
-
           :error ->
             raise KeyError, key: key, term: dict
         end
       end
 
-      @deprecated message
       def pop(dict, key, default \\ nil) do
         case fetch(dict, key) do
           {:ok, value} ->
             {value, delete(dict, key)}
-
           :error ->
             {default, dict}
         end
       end
 
-      @deprecated message
       def pop_lazy(dict, key, fun) when is_function(fun, 0) do
         case fetch(dict, key) do
           {:ok, value} ->
             {value, delete(dict, key)}
-
           :error ->
             {fun.(), dict}
         end
       end
 
-      @deprecated message
       def split(dict, keys) do
         Enum.reduce(keys, {new(), dict}, fn key, {inc, exc} = acc ->
           case fetch(exc, key) do
             {:ok, value} ->
               {put(inc, key, value), delete(exc, key)}
-
             :error ->
               acc
           end
         end)
       end
 
-      defoverridable merge: 2,
-                     merge: 3,
-                     equal?: 2,
-                     to_list: 1,
-                     keys: 1,
-                     values: 1,
-                     take: 2,
-                     drop: 2,
-                     get: 2,
-                     get: 3,
-                     fetch!: 2,
-                     has_key?: 2,
-                     put_new: 3,
-                     pop: 2,
-                     pop: 3,
-                     split: 2,
-                     update: 4,
-                     update!: 3,
-                     get_and_update: 3,
-                     get_lazy: 3,
-                     pop_lazy: 3,
-                     put_new_lazy: 3
+      defoverridable merge: 2, merge: 3, equal?: 2, to_list: 1, keys: 1,
+                     values: 1, take: 2, drop: 2, get: 2, get: 3, fetch!: 2,
+                     has_key?: 2, put_new: 3, pop: 2, pop: 3, split: 2,
+                     update: 4, update!: 3, get_and_update: 3, get_lazy: 3,
+                     pop_lazy: 3, put_new_lazy: 3
     end
   end
 
   defmacrop target(dict) do
     quote do
       case unquote(dict) do
-        %module{} -> module
-        %{} -> Map
-        dict when is_list(dict) -> Keyword
-        dict -> unsupported_dict(dict)
+        %{__struct__: x} when is_atom(x) ->
+          x
+        %{} ->
+          Map
+        x when is_list(x) ->
+          Keyword
+        x ->
+          unsupported_dict(x)
       end
     end
   end
 
-  @deprecated message
   @spec keys(t) :: [key]
   def keys(dict) do
     target(dict).keys(dict)
   end
 
-  @deprecated message
   @spec values(t) :: [value]
   def values(dict) do
     target(dict).values(dict)
   end
 
-  @deprecated message
   @spec size(t) :: non_neg_integer
   def size(dict) do
     target(dict).size(dict)
   end
 
-  @deprecated message
   @spec has_key?(t, key) :: boolean
   def has_key?(dict, key) do
     target(dict).has_key?(dict, key)
   end
 
-  @deprecated message
   @spec get(t, key, value) :: value
   def get(dict, key, default \\ nil) do
     target(dict).get(dict, key, default)
   end
 
-  @deprecated message
   @spec get_lazy(t, key, (() -> value)) :: value
   def get_lazy(dict, key, fun) do
     target(dict).get_lazy(dict, key, fun)
   end
 
-  @deprecated message
   @spec get_and_update(t, key, (value -> {value, value})) :: {value, t}
   def get_and_update(dict, key, fun) do
     target(dict).get_and_update(dict, key, fun)
   end
 
-  @deprecated message
   @spec fetch(t, key) :: value
   def fetch(dict, key) do
     target(dict).fetch(dict, key)
   end
 
-  @deprecated message
-  @spec fetch!(t, key) :: value
+  @spec fetch!(t, key) :: value | no_return
   def fetch!(dict, key) do
     target(dict).fetch!(dict, key)
   end
 
-  @deprecated message
   @spec put(t, key, value) :: t
   def put(dict, key, val) do
     target(dict).put(dict, key, val)
   end
 
-  @deprecated message
   @spec put_new(t, key, value) :: t
   def put_new(dict, key, val) do
     target(dict).put_new(dict, key, val)
   end
 
-  @deprecated message
   @spec put_new_lazy(t, key, (() -> value)) :: t
   def put_new_lazy(dict, key, fun) do
     target(dict).put_new_lazy(dict, key, fun)
   end
 
-  @deprecated message
   @spec delete(t, key) :: t
   def delete(dict, key) do
     target(dict).delete(dict, key)
   end
 
-  @deprecated message
   @spec merge(t, t) :: t
   def merge(dict1, dict2) do
     target1 = target(dict1)
@@ -334,11 +272,10 @@ defmodule Dict do
     if target1 == target2 do
       target1.merge(dict1, dict2)
     else
-      do_merge(target1, dict1, dict2, fn _k, _v1, v2 -> v2 end)
+      do_merge(target1, dict1, dict2, fn(_k, _v1, v2) -> v2 end)
     end
   end
 
-  @deprecated message
   @spec merge(t, t, (key, value, value -> value)) :: t
   def merge(dict1, dict2, fun) do
     target1 = target(dict1)
@@ -352,61 +289,51 @@ defmodule Dict do
   end
 
   defp do_merge(target1, dict1, dict2, fun) do
-    Enumerable.reduce(dict2, {:cont, dict1}, fn {k, v}, acc ->
-      {:cont, target1.update(acc, k, v, fn other -> fun.(k, other, v) end)}
-    end)
-    |> elem(1)
+    Enumerable.reduce(dict2, {:cont, dict1}, fn({k, v}, acc) ->
+      {:cont, target1.update(acc, k, v, fn(other) -> fun.(k, other, v) end)}
+    end) |> elem(1)
   end
 
-  @deprecated message
   @spec pop(t, key, value) :: {value, t}
   def pop(dict, key, default \\ nil) do
     target(dict).pop(dict, key, default)
   end
 
-  @deprecated message
   @spec pop_lazy(t, key, (() -> value)) :: {value, t}
   def pop_lazy(dict, key, fun) do
     target(dict).pop_lazy(dict, key, fun)
   end
 
-  @deprecated message
   @spec update!(t, key, (value -> value)) :: t
   def update!(dict, key, fun) do
     target(dict).update!(dict, key, fun)
   end
 
-  @deprecated message
   @spec update(t, key, value, (value -> value)) :: t
-  def update(dict, key, default, fun) do
-    target(dict).update(dict, key, default, fun)
+  def update(dict, key, initial, fun) do
+    target(dict).update(dict, key, initial, fun)
   end
 
-  @deprecated message
   @spec split(t, [key]) :: {t, t}
   def split(dict, keys) do
     target(dict).split(dict, keys)
   end
 
-  @deprecated message
   @spec drop(t, [key]) :: t
   def drop(dict, keys) do
     target(dict).drop(dict, keys)
   end
 
-  @deprecated message
   @spec take(t, [key]) :: t
   def take(dict, keys) do
     target(dict).take(dict, keys)
   end
 
-  @deprecated message
   @spec empty(t) :: t
   def empty(dict) do
     target(dict).empty(dict)
   end
 
-  @deprecated message
   @spec equal?(t, t) :: boolean
   def equal?(dict1, dict2) do
     target1 = target(dict1)
@@ -417,20 +344,18 @@ defmodule Dict do
         target1.equal?(dict1, dict2)
 
       target1.size(dict1) == target2.size(dict2) ->
-        Enumerable.reduce(dict2, {:cont, true}, fn {k, v}, _acc ->
+        Enumerable.reduce(dict2, {:cont, true}, fn({k, v}, _acc) ->
           case target1.fetch(dict1, k) do
             {:ok, ^v} -> {:cont, true}
-            _ -> {:halt, false}
+            _         -> {:halt, false}
           end
-        end)
-        |> elem(1)
+        end) |> elem(1)
 
       true ->
         false
     end
   end
 
-  @deprecated message
   @spec to_list(t) :: list
   def to_list(dict) do
     target(dict).to_list(dict)
@@ -438,6 +363,6 @@ defmodule Dict do
 
   @spec unsupported_dict(t) :: no_return
   defp unsupported_dict(dict) do
-    raise ArgumentError, "unsupported dict: #{inspect(dict)}"
+    raise ArgumentError, "unsupported dict: #{inspect dict}"
   end
 end

lib/elixir/lib/file/stat.ex

@@ -12,7 +12,7 @@ defmodule File.Stat do
 
     * `size` - size of file in bytes.
 
-    * `type` - `:device | :directory | :regular | :other | :symlink`; the type of the
+    * `type` - `:device | :directory | :regular | :other`; the type of the
       file.
 
     * `access` - `:read | :write | :read_write | :none`; the current system
@@ -23,7 +23,7 @@ defmodule File.Stat do
     * `mtime` - the last time the file was written.
 
     * `ctime` - the interpretation of this time field depends on the operating
-      system. On Unix-like operating systems, it is the last time the file or the inode was changed.
+      system. On Unix, it is the last time the file or the inode was changed.
       In Windows, it is the time of creation.
 
     * `mode` - the file permissions.
@@ -35,17 +35,17 @@ defmodule File.Stat do
       In Windows, the number indicates a drive as follows: 0 means A:, 1 means
       B:, and so on.
 
-    * `minor_device` - only valid for character devices on Unix-like systems. In all other
+    * `minor_device` - only valid for character devices on Unix. In all other
       cases, this field is zero.
 
-    * `inode` - gives the inode number. On non-Unix-like file systems, this field
+    * `inode` - gives the inode number. On non-Unix file systems, this field
       will be zero.
 
-    * `uid` - indicates the owner of the file. Will be zero for non-Unix-like file
+    * `uid` - indicates the owner of the file. Will be zero for non-Unix file
       systems.
 
     * `gid` - indicates the group that owns the file. Will be zero for
-      non-Unix-like file systems.
+      non-Unix file systems.
 
   The time type returned in `atime`, `mtime`, and `ctime` is dependent on the
   time type set in options. `{:time, type}` where type can be `:local`,
@@ -53,32 +53,16 @@ defmodule File.Stat do
   """
 
   record = Record.extract(:file_info, from_lib: "kernel/include/file.hrl")
-  keys = :lists.map(&elem(&1, 0), record)
-  vals = :lists.map(&{&1, [], nil}, keys)
-  pairs = :lists.zip(keys, vals)
+  keys   = :lists.map(&elem(&1, 0), record)
+  vals   = :lists.map(&{&1, [], nil}, keys)
+  pairs  = :lists.zip(keys, vals)
 
   defstruct keys
-
-  @type t :: %__MODULE__{
-          size: non_neg_integer(),
-          type: :device | :directory | :regular | :other | :symlink,
-          access: :read | :write | :read_write | :none,
-          atime: :calendar.datetime() | integer(),
-          mtime: :calendar.datetime() | integer(),
-          ctime: :calendar.datetime() | integer(),
-          mode: non_neg_integer(),
-          links: non_neg_integer(),
-          major_device: non_neg_integer(),
-          minor_device: non_neg_integer(),
-          inode: non_neg_integer(),
-          uid: non_neg_integer(),
-          gid: non_neg_integer()
-        }
+  @type t :: %__MODULE__{}
 
   @doc """
   Converts a `File.Stat` struct to a `:file_info` record.
   """
-  @spec to_record(t()) :: :file.file_info()
   def to_record(%File.Stat{unquote_splicing(pairs)}) do
     {:file_info, unquote_splicing(vals)}
   end
@@ -86,9 +70,7 @@ defmodule File.Stat do
   @doc """
   Converts a `:file_info` record into a `File.Stat`.
   """
-  @spec from_record(:file.file_info()) :: t()
   def from_record(file_info)
-
   def from_record({:file_info, unquote_splicing(vals)}) do
     %File.Stat{unquote_splicing(pairs)}
   end

lib/elixir/lib/file/stream.ex

@@ -7,7 +7,7 @@ defmodule File.Stream do
     * `path`          - the file path
     * `modes`         - the file modes
     * `raw`           - a boolean indicating if bin functions should be used
-    * `line_or_bytes` - if reading should read lines or a given number of bytes
+    * `line_or_bytes` - if reading should read lines or a given amount of bytes
 
   """
 
@@ -22,12 +22,11 @@ defmodule File.Stream do
     modes =
       case raw do
         true ->
-          case :lists.keyfind(:read_ahead, 1, modes) do
-            {:read_ahead, false} -> [:raw | :lists.keydelete(:read_ahead, 1, modes)]
-            {:read_ahead, _} -> [:raw | modes]
-            false -> [:raw, :read_ahead | modes]
+          if :lists.keyfind(:read_ahead, 1, modes) == {:read_ahead, false} do
+            [:raw | modes]
+          else
+            [:raw, :read_ahead | modes]
           end
-
         false ->
           modes
       end
@@ -37,12 +36,11 @@ defmodule File.Stream do
 
   defimpl Collectable do
     def into(%{path: path, modes: modes, raw: raw} = stream) do
-      modes = for mode <- modes, mode not in [:read], do: mode
+      modes = for mode <- modes, not mode in [:read], do: mode
 
       case :file.open(path, [:write | modes]) do
         {:ok, device} ->
           {:ok, into(device, stream, raw)}
-
         {:error, reason} ->
           raise File.Error, reason: reason, action: "stream", path: path
       end
@@ -52,16 +50,14 @@ defmodule File.Stream do
       fn
         :ok, {:cont, x} ->
           case raw do
-            true -> IO.binwrite(device, x)
+            true  -> IO.binwrite(device, x)
             false -> IO.write(device, x)
           end
-
         :ok, :done ->
           # If delayed_write option is used and the last write failed will
           # MatchError here as {:error, _} is returned.
           :ok = :file.close(device)
           stream
-
         :ok, :halt ->
           # If delayed_write option is used and the last write failed will
           # MatchError here as {:error, _} is returned.
@@ -71,55 +67,27 @@ defmodule File.Stream do
   end
 
   defimpl Enumerable do
-    @read_ahead_size 64 * 1024
-
     def reduce(%{path: path, modes: modes, line_or_bytes: line_or_bytes, raw: raw}, acc, fun) do
-      start_fun = fn ->
-        case :file.open(path, read_modes(modes)) do
-          {:ok, device} ->
-            if :trim_bom in modes, do: trim_bom(device, raw) |> elem(0), else: device
+      modes = for mode <- modes, not mode in [:write, :append], do: mode
 
-          {:error, reason} ->
-            raise File.Error, reason: reason, action: "stream", path: path
+      start_fun =
+        fn ->
+          case :file.open(path, modes) do
+            {:ok, device}    -> device
+            {:error, reason} ->
+              raise File.Error, reason: reason, action: "stream", path: path
+          end
         end
-      end
 
       next_fun =
         case raw do
-          true -> &IO.each_binstream(&1, line_or_bytes)
+          true  -> &IO.each_binstream(&1, line_or_bytes)
           false -> &IO.each_stream(&1, line_or_bytes)
         end
 
       Stream.resource(start_fun, next_fun, &:file.close/1).(acc, fun)
     end
 
-    def count(%{path: path, modes: modes, line_or_bytes: :line} = stream) do
-      pattern = :binary.compile_pattern("\n")
-      counter = &count_lines(&1, path, pattern, read_function(stream), 0)
-
-      case File.open(path, read_modes(modes), counter) do
-        {:ok, count} ->
-          {:ok, count}
-
-        {:error, reason} ->
-          raise File.Error, reason: reason, action: "stream", path: path
-      end
-    end
-
-    def count(%{path: path, line_or_bytes: bytes, raw: true, modes: modes}) do
-      case File.stat(path) do
-        {:ok, %{size: 0}} ->
-          {:error, __MODULE__}
-
-        {:ok, %{size: size}} ->
-          remainder = if rem(size, bytes) == 0, do: 0, else: 1
-          {:ok, div(size, bytes) + remainder - count_raw_bom(path, modes)}
-
-        {:error, reason} ->
-          raise File.Error, reason: reason, action: "stream", path: path
-      end
-    end
-
     def count(_stream) do
       {:error, __MODULE__}
     end
@@ -127,64 +95,5 @@ defmodule File.Stream do
     def member?(_stream, _term) do
       {:error, __MODULE__}
     end
-
-    def slice(_stream) do
-      {:error, __MODULE__}
-    end
-
-    defp count_raw_bom(path, modes) do
-      if :trim_bom in modes do
-        File.open!(path, read_modes(modes), &(&1 |> trim_bom(true) |> elem(1)))
-      else
-        0
-      end
-    end
-
-    defp trim_bom(device, true) do
-      bom_length = device |> IO.binread(4) |> bom_length()
-      {:ok, new_pos} = :file.position(device, bom_length)
-      {device, new_pos}
-    end
-
-    defp trim_bom(device, false) do
-      # Or we read the bom in the correct amount or it isn't there
-      case bom_length(IO.read(device, 1)) do
-        0 ->
-          {:ok, _} = :file.position(device, 0)
-          {device, 0}
-
-        _ ->
-          {device, 1}
-      end
-    end
-
-    defp bom_length(<<239, 187, 191, _rest::binary>>), do: 3
-    defp bom_length(<<254, 255, _rest::binary>>), do: 2
-    defp bom_length(<<255, 254, _rest::binary>>), do: 2
-    defp bom_length(<<0, 0, 254, 255, _rest::binary>>), do: 4
-    defp bom_length(<<254, 255, 0, 0, _rest::binary>>), do: 4
-    defp bom_length(_binary), do: 0
-
-    defp read_modes(modes) do
-      for mode <- modes, mode not in [:write, :append, :trim_bom], do: mode
-    end
-
-    defp count_lines(device, path, pattern, read, count) do
-      case read.(device) do
-        data when is_binary(data) ->
-          count_lines(device, path, pattern, read, count + count_lines(data, pattern))
-
-        :eof ->
-          count
-
-        {:error, reason} ->
-          raise File.Error, reason: reason, action: "stream", path: path
-      end
-    end
-
-    defp count_lines(data, pattern), do: length(:binary.matches(data, pattern))
-
-    defp read_function(%{raw: true}), do: &IO.binread(&1, @read_ahead_size)
-    defp read_function(%{raw: false}), do: &IO.read(&1, @read_ahead_size)
   end
 end

lib/elixir/lib/float.ex

@@ -2,89 +2,12 @@ import Kernel, except: [round: 1]
 
 defmodule Float do
   @moduledoc """
-  Functions for working with floating-point numbers.
-
-  ## Kernel functions
-
-  There are functions related to floating-point numbers on the `Kernel` module
-  too. Here is a list of them:
-
-    * `Kernel.round/1`: rounds a number to the nearest integer.
-    * `Kernel.trunc/1`: returns the integer part of a number.
-
-  ## Known issues
-
-  There are some very well known problems with floating-point numbers
-  and arithmetics due to the fact most decimal fractions cannot be
-  represented by a floating-point binary and most operations are not exact,
-  but operate on approximations. Those issues are not specific
-  to Elixir, they are a property of floating point representation itself.
-
-  For example, the numbers 0.1 and 0.01 are two of them, what means the result
-  of squaring 0.1 does not give 0.01 neither the closest representable. Here is
-  what happens in this case:
-
-    * The closest representable number to 0.1 is 0.1000000014
-    * The closest representable number to 0.01 is 0.0099999997
-    * Doing 0.1 * 0.1 should return 0.01, but because 0.1 is actually 0.1000000014,
-      the result is 0.010000000000000002, and because this is not the closest
-      representable number to 0.01, you'll get the wrong result for this operation
-
-  There are also other known problems like flooring or rounding numbers. See
-  `round/2` and `floor/2` for more details about them.
-
-  To learn more about floating-point arithmetic visit:
-
-    * [0.30000000000000004.com](http://0.30000000000000004.com/)
-    * [What Every Programmer Should Know About Floating-Point Arithmetic](https://floating-point-gui.de/)
-
+  Functions for working with floating point numbers.
   """
 
   import Bitwise
 
-  @power_of_2_to_52 4_503_599_627_370_496
-  @precision_range 0..15
-  @type precision_range :: 0..15
-
-  @doc """
-  Computes `base` raised to power of `exponent`.
-
-  `base` must be a float and `exponent` can be any number.
-  However, if a negative base and a fractional exponent
-  are given, it raises `ArithmeticError`.
-
-  It always returns a float. See `Integer.pow/2` for
-  exponentiation that returns integers.
-
-  ## Examples
-
-      iex> Float.pow(2.0, 0)
-      1.0
-      iex> Float.pow(2.0, 1)
-      2.0
-      iex> Float.pow(2.0, 10)
-      1024.0
-      iex> Float.pow(2.0, -1)
-      0.5
-      iex> Float.pow(2.0, -3)
-      0.125
-
-      iex> Float.pow(3.0, 1.5)
-      5.196152422706632
-
-      iex> Float.pow(-2.0, 3)
-      -8.0
-      iex> Float.pow(-2.0, 4)
-      16.0
-
-      iex> Float.pow(-1.0, 0.5)
-      ** (ArithmeticError) bad argument in arithmetic expression
-
-  """
-  @doc since: "1.12.0"
-  @spec pow(float, number) :: float
-  def pow(base, exponent) when is_float(base) and is_number(exponent),
-    do: :math.pow(base, exponent)
+  @power_of_2_to_52 4503599627370496
 
   @doc """
   Parses a binary into a float.
@@ -128,44 +51,38 @@ defmodule Float do
     parse_unsigned(binary)
   end
 
-  defp parse_unsigned(<<digit, rest::binary>>) when digit in ?0..?9,
-    do: parse_unsigned(rest, false, false, <<digit>>)
+  defp parse_unsigned(<<digit, rest::binary>>) when digit in ?0..?9, do:
+    parse_unsigned(rest, false, false, <<digit>>)
 
-  defp parse_unsigned(binary) when is_binary(binary), do: :error
+  defp parse_unsigned(binary) when is_binary(binary), do:
+    :error
 
-  defp parse_unsigned(<<digit, rest::binary>>, dot?, e?, acc) when digit in ?0..?9,
-    do: parse_unsigned(rest, dot?, e?, <<acc::binary, digit>>)
+  defp parse_unsigned(<<digit, rest::binary>>, dot?, e?, acc) when digit in ?0..?9, do:
+    parse_unsigned(rest, dot?, e?, <<acc::binary, digit>>)
 
-  defp parse_unsigned(<<?., digit, rest::binary>>, false, false, acc) when digit in ?0..?9,
-    do: parse_unsigned(rest, true, false, <<acc::binary, ?., digit>>)
+  defp parse_unsigned(<<?., digit, rest::binary>>, false, false, acc) when digit in ?0..?9, do:
+    parse_unsigned(rest, true, false, <<acc::binary, ?., digit>>)
 
-  defp parse_unsigned(<<exp_marker, digit, rest::binary>>, dot?, false, acc)
-       when exp_marker in 'eE' and digit in ?0..?9,
-       do: parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, digit>>)
+  defp parse_unsigned(<<exp_marker, digit, rest::binary>>, dot?, false, acc) when exp_marker in 'eE' and  digit in ?0..?9, do:
+    parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, digit>>)
 
-  defp parse_unsigned(<<exp_marker, sign, digit, rest::binary>>, dot?, false, acc)
-       when exp_marker in 'eE' and sign in '-+' and digit in ?0..?9,
-       do: parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, sign, digit>>)
+  defp parse_unsigned(<<exp_marker, sign, digit, rest::binary>>, dot?, false, acc) when exp_marker in 'eE' and sign in '-+' and digit in ?0..?9, do:
+    parse_unsigned(rest, true, true, <<add_dot(acc, dot?)::binary, ?e, sign, digit>>)
 
-  defp parse_unsigned(rest, dot?, _e?, acc),
-    do: {:erlang.binary_to_float(add_dot(acc, dot?)), rest}
+  defp parse_unsigned(rest, dot?, _e?, acc), do:
+    {:erlang.binary_to_float(add_dot(acc, dot?)), rest}
 
-  defp add_dot(acc, true), do: acc
+  defp add_dot(acc, true),  do: acc
   defp add_dot(acc, false), do: acc <> ".0"
 
   @doc """
-  Rounds a float to the largest number less than or equal to `num`.
+  Rounds a float to the largest integer less than or equal to `num`.
 
-  `floor/2` also accepts a precision to round a floating-point value down
+  `floor/2` also accepts a precision to round a floating point value down
   to an arbitrary number of fractional digits (between 0 and 15).
   The operation is performed on the binary floating point, without a
   conversion to decimal.
 
-  This function always returns a float. `Kernel.trunc/1` may be used instead to
-  truncate the result to an integer afterwards.
-
-  ## Known issues
-
   The behaviour of `floor/2` for floats can be surprising. For example:
 
       iex> Float.floor(12.52, 2)
@@ -176,6 +93,9 @@ defmodule Float do
   and therefore the number above is internally represented as 12.51999999,
   which explains the behaviour above.
 
+  This function always returns a float. `Kernel.trunc/1` may be used instead to
+  truncate the result to an integer afterwards.
+
   ## Examples
 
       iex> Float.floor(34.25)
@@ -186,25 +106,15 @@ defmodule Float do
       34.25
 
   """
-  @spec floor(float, precision_range) :: float
-  def floor(number, precision \\ 0)
-
-  def floor(number, 0) when is_float(number) do
-    :math.floor(number)
-  end
-
-  def floor(number, precision) when is_float(number) and precision in @precision_range do
+  @spec floor(float, 0..15) :: float
+  def floor(number, precision \\ 0) when is_float(number) and precision in 0..15 do
     round(number, precision, :floor)
   end
 
-  def floor(number, precision) when is_float(number) do
-    raise ArgumentError, invalid_precision_message(precision)
-  end
-
   @doc """
   Rounds a float to the smallest integer greater than or equal to `num`.
 
-  `ceil/2` also accepts a precision to round a floating-point value down
+  `ceil/2` also accepts a precision to round a floating point value down
   to an arbitrary number of fractional digits (between 0 and 15).
 
   The operation is performed on the binary floating point, without a
@@ -233,23 +143,13 @@ defmodule Float do
       34.26
 
   """
-  @spec ceil(float, precision_range) :: float
-  def ceil(number, precision \\ 0)
-
-  def ceil(number, 0) when is_float(number) do
-    :math.ceil(number)
-  end
-
-  def ceil(number, precision) when is_float(number) and precision in @precision_range do
+  @spec ceil(float, 0..15) :: float
+  def ceil(number, precision \\ 0) when is_float(number) and precision in 0..15 do
     round(number, precision, :ceil)
   end
 
-  def ceil(number, precision) when is_float(number) do
-    raise ArgumentError, invalid_precision_message(precision)
-  end
-
   @doc """
-  Rounds a floating-point value to an arbitrary number of fractional
+  Rounds a floating point value to an arbitrary number of fractional
   digits (between 0 and 15).
 
   The rounding direction always ties to half up. The operation is
@@ -259,8 +159,6 @@ defmodule Float do
   `Kernel.round/1` if you want a function that accepts both floats
   and integers and always returns an integer.
 
-  ## Known issues
-
   The behaviour of `round/2` for floats can be surprising. For example:
 
       iex> Float.round(5.5675, 3)
@@ -290,42 +188,33 @@ defmodule Float do
       12.341444444444441
 
   """
-  @spec round(float, precision_range) :: float
+  @spec round(float, 0..15) :: float
+
   # This implementation is slow since it relies on big integers.
   # Faster implementations are available on more recent papers
   # and could be implemented in the future.
-  def round(float, precision \\ 0)
-
-  def round(float, 0) when is_float(float) do
-    float |> :erlang.round() |> :erlang.float()
-  end
-
-  def round(float, precision) when is_float(float) and precision in @precision_range do
+  def round(float, precision \\ 0) when is_float(float) and precision in 0..15 do
     round(float, precision, :half_up)
   end
 
-  def round(float, precision) when is_float(float) do
-    raise ArgumentError, invalid_precision_message(precision)
-  end
-
-  defp round(0.0 = num, _precision, _rounding), do: num
-
   defp round(float, precision, rounding) do
     <<sign::1, exp::11, significant::52-bitstring>> = <<float::float>>
-    {num, count} = decompose(significant, 1)
+    {num, count, _} = decompose(significant)
     count = count - exp + 1023
 
     cond do
-      # Precision beyond 15 digits
-      count >= 104 ->
+      count <= 0 or  # There is no decimal precision
+      (0 == exp and <<0::52>> == significant) -> #zero or minus zero
+        float
+
+      count >= 104 -> # Precision beyond 15 digits
         case rounding do
           :ceil when sign === 0 -> 1 / power_of_10(precision)
           :floor when sign === 1 -> -1 / power_of_10(precision)
           _ -> 0.0
         end
 
-      # We are asking more precision than we have
-      count <= precision ->
+      count <= precision -> # We are asking more precision than we have
         float
 
       true ->
@@ -345,18 +234,16 @@ defmodule Float do
         num = rounding(rounding, sign, num, div)
 
         # Convert back to float without loss
-        # https://www.exploringbinary.com/correct-decimal-to-floating-point-using-big-integers/
+        # http://www.exploringbinary.com/correct-decimal-to-floating-point-using-big-integers/
         den = power_of_10(precision)
         boundary = den <<< 52
 
         cond do
           num == 0 ->
             0.0
-
           num >= boundary ->
             {den, exp} = scale_down(num, boundary, 52)
             decimal_to_float(sign, num, den, exp)
-
           true ->
             {num, exp} = scale_up(num, boundary, 52)
             decimal_to_float(sign, num, den, exp)
@@ -364,28 +251,11 @@ defmodule Float do
     end
   end
 
-  defp decompose(significant, initial) do
-    decompose(significant, 1, 0, initial)
-  end
-
-  defp decompose(<<1::1, bits::bitstring>>, count, last_count, acc) do
-    decompose(bits, count + 1, count, (acc <<< (count - last_count)) + 1)
-  end
-
-  defp decompose(<<0::1, bits::bitstring>>, count, last_count, acc) do
-    decompose(bits, count + 1, last_count, acc)
-  end
-
-  defp decompose(<<>>, _count, last_count, acc) do
-    {acc, last_count}
-  end
-
   defp scale_up(num, boundary, exp) when num >= boundary, do: {num, exp}
   defp scale_up(num, boundary, exp), do: scale_up(num <<< 1, boundary, exp - 1)
 
   defp scale_down(num, den, exp) do
     new_den = den <<< 1
-
     if num < new_den do
       {den >>> 52, exp}
     else
@@ -406,31 +276,29 @@ defmodule Float do
       end
 
     tmp = tmp - @power_of_2_to_52
-    <<tmp::float>> = <<sign::1, exp + 1023::11, tmp::52>>
+    <<tmp::float>> = <<sign::1, (exp + 1023)::11, tmp::52>>
     tmp
   end
 
   defp rounding(:floor, 1, _num, div), do: div + 1
   defp rounding(:ceil, 0, _num, div), do: div + 1
-
   defp rounding(:half_up, _sign, num, div) do
     case rem(num, 10) do
       rem when rem < 5 -> div
       rem when rem >= 5 -> div + 1
     end
   end
-
   defp rounding(_, _, _, div), do: div
 
-  Enum.reduce(0..104, 1, fn x, acc ->
+  Enum.reduce 0..104, 1, fn x, acc ->
     defp power_of_10(unquote(x)), do: unquote(acc)
     acc * 10
-  end)
+  end
 
-  Enum.reduce(0..104, 1, fn x, acc ->
+  Enum.reduce 0..104, 1, fn x, acc ->
     defp power_of_5(unquote(x)), do: unquote(acc)
     acc * 5
-  end)
+  end
 
   @doc """
   Returns a pair of integers whose ratio is exactly equal
@@ -438,8 +306,6 @@ defmodule Float do
 
   ## Examples
 
-      iex> Float.ratio(0.0)
-      {0, 1}
       iex> Float.ratio(3.14)
       {7070651414971679, 2251799813685248}
       iex> Float.ratio(-3.14)
@@ -454,60 +320,45 @@ defmodule Float do
       {-16, 1}
 
   """
-  @doc since: "1.4.0"
-  @spec ratio(float) :: {integer, pos_integer}
-  def ratio(0.0), do: {0, 1}
-
   def ratio(float) when is_float(float) do
-    <<sign::1, exp::11, mantissa::52>> = <<float::float>>
-
-    {num, den_exp} =
-      if exp != 0 do
-        # Floats are expressed like this:
-        # (2**52 + mantissa) * 2**(-52 + exp - 1023)
-        #
-        # We compute the root factors of the mantissa so we have this:
-        # (2**52 + mantissa * 2**count) * 2**(-52 + exp - 1023)
-        {mantissa, count} = root_factors(mantissa, 0)
-
-        # Now we can move the count around so we have this:
-        # (2**(52-count) + mantissa) * 2**(count + -52 + exp - 1023)
-        if mantissa == 0 do
-          {1, exp - 1023}
-        else
-          num = (1 <<< (52 - count)) + mantissa
-          den_exp = count - 52 + exp - 1023
-          {num, den_exp}
-        end
-      else
-        # Subnormals are expressed like this:
-        # (mantissa) * 2**(-52 + 1 - 1023)
-        #
-        # So we compute it to this:
-        # (mantissa * 2**(count)) * 2**(-52 + 1 - 1023)
-        #
-        # Which becomes:
-        # mantissa * 2**(count-1074)
-        root_factors(mantissa, -1074)
-      end
-
-    if den_exp > 0 do
-      {sign(sign, num <<< den_exp), 1}
-    else
-      {sign(sign, num), 1 <<< -den_exp}
+    <<sign::1, exp::11, significant::52-bitstring>> = <<float::float>>
+    {num, _, den} = decompose(significant)
+    num = sign(sign, num)
+    case exp - 1023 do
+      exp when exp > 0 ->
+        {den, exp} = shift_right(den, exp)
+        {shift_left(num, exp), den}
+      exp when exp < 0 ->
+        {num, shift_left(den, -exp)}
+      0 ->
+        {num, den}
     end
   end
 
-  defp root_factors(mantissa, count) when mantissa != 0 and (mantissa &&& 1) == 0,
-    do: root_factors(mantissa >>> 1, count + 1)
+  defp decompose(significant) do
+    decompose(significant, 1, 0, 2, 1, 1)
+  end
 
-  defp root_factors(mantissa, count),
-    do: {mantissa, count}
+  defp decompose(<<1::1, bits::bitstring>>, count, last_count, power, _last_power, acc) do
+    decompose(bits, count + 1, count, power <<< 1, power, shift_left(acc, count - last_count) + 1)
+  end
+  defp decompose(<<0::1, bits::bitstring>>, count, last_count, power, last_power, acc) do
+    decompose(bits, count + 1, last_count, power <<< 1, last_power, acc)
+  end
+  defp decompose(<<>>, _count, last_count, _power, last_power, acc) do
+    {acc, last_count, last_power}
+  end
 
-  @compile {:inline, sign: 2}
   defp sign(0, num), do: num
   defp sign(1, num), do: -num
 
+  defp shift_left(num, 0), do: num
+  defp shift_left(num, times), do: shift_left(num <<< 1, times - 1)
+
+  defp shift_right(num, 0), do: {num, 0}
+  defp shift_right(1, times), do: {1, times}
+  defp shift_right(num, times), do: shift_right(num >>> 1, times - 1)
+
   @doc """
   Returns a charlist which corresponds to the text representation
   of the given float.
@@ -543,33 +394,29 @@ defmodule Float do
       "7.0"
 
   """
-  @spec to_string(float) :: String.t()
+  @spec to_string(float) :: String.t
   def to_string(float) when is_float(float) do
     IO.iodata_to_binary(:io_lib_format.fwrite_g(float))
   end
 
+  # TODO: Deprecate by v1.5
   @doc false
-  @deprecated "Use Float.to_charlist/1 instead"
   def to_char_list(float), do: Float.to_charlist(float)
 
   @doc false
-  @deprecated "Use :erlang.float_to_list/2 instead"
   def to_char_list(float, options) do
+    IO.warn "Float.to_char_list/2 is deprecated, use :erlang.float_to_list/2 instead"
     :erlang.float_to_list(float, expand_compact(options))
   end
 
   @doc false
-  @deprecated "Use :erlang.float_to_binary/2 instead"
   def to_string(float, options) do
+    IO.warn "Float.to_string/2 is deprecated, use :erlang.float_to_binary/2 instead"
     :erlang.float_to_binary(float, expand_compact(options))
   end
 
-  defp invalid_precision_message(precision) do
-    "precision #{precision} is out of valid range of #{inspect(@precision_range)}"
-  end
-
   defp expand_compact([{:compact, false} | t]), do: expand_compact(t)
-  defp expand_compact([{:compact, true} | t]), do: [:compact | expand_compact(t)]
-  defp expand_compact([h | t]), do: [h | expand_compact(t)]
-  defp expand_compact([]), do: []
+  defp expand_compact([{:compact, true} | t]),  do: [:compact | expand_compact(t)]
+  defp expand_compact([h | t]),                 do: [h | expand_compact(t)]
+  defp expand_compact([]),                      do: []
 end

lib/elixir/lib/function.ex

@@ -1,208 +0,0 @@
-defmodule Function do
-  @moduledoc """
-  A set of functions for working with functions.
-
-  Anonymous functions are typically created by using `fn`:
-
-      iex> add = fn a, b -> a + b end
-      iex> add.(1, 2)
-      3
-
-  Anonymous functions can also have multiple clauses. All clauses
-  should expect the same number of arguments:
-
-      iex> negate = fn
-      ...>   true -> false
-      ...>   false -> true
-      ...> end
-      iex> negate.(false)
-      true
-
-  ## The capture operator
-
-  It is also possible to capture public module functions and pass them
-  around as if they were anonymous functions by using the capture
-  operator `Kernel.SpecialForms.&/1`:
-
-      iex> add = &Kernel.+/2
-      iex> add.(1, 2)
-      3
-
-      iex> length = &String.length/1
-      iex> length.("hello")
-      5
-
-  To capture a definition within the current module, you can skip the
-  module prefix, such as `&my_fun/2`. In those cases, the captured
-  function can be public (`def`) or private (`defp`).
-
-  The capture operator can also be used to create anonymous functions
-  that expect at least one argument:
-
-      iex> add = &(&1 + &2)
-      iex> add.(1, 2)
-      3
-
-  In such cases, using the capture operator is no different than using `fn`.
-
-  ## Internal and external functions
-
-  We say that functions that point to definitions residing in modules, such
-  as `&String.length/1`, are **external** functions. All other functions are
-  **local** and they are always bound to the file or module that defined them.
-
-  Besides the functions in this module to work with functions, `Kernel` also
-  has an `apply/2` function that invokes a function with a dynamic number of
-  arguments, as well as `is_function/1` and `is_function/2`, to check
-  respectively if a given value is a function or a function of a given arity.
-  """
-
-  @type information ::
-          :arity
-          | :env
-          | :index
-          | :module
-          | :name
-          | :new_index
-          | :new_uniq
-          | :pid
-          | :type
-          | :uniq
-
-  @doc """
-  Captures the given function.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> Function.capture(String, :length, 1)
-      &String.length/1
-
-  """
-  @doc since: "1.7.0"
-  @spec capture(module, atom, arity) :: fun
-  def capture(module, function_name, arity) do
-    :erlang.make_fun(module, function_name, arity)
-  end
-
-  @doc """
-  Returns a keyword list with information about a function.
-
-  The returned keys (with the corresponding possible values) for
-  all types of functions (local and external) are the following:
-
-    * `:type` - `:local` (for anonymous functions) or `:external` (for
-      named functions).
-
-    * `:module` - an atom which is the module where the function is defined when
-    anonymous or the module which the function refers to when it's a named function.
-
-    * `:arity` - (integer) the number of arguments the function is to be called with.
-
-    * `:name` - (atom) the name of the function.
-
-    * `:env` - a list of the environment or free variables. For named
-      functions, the returned list is always empty.
-
-  When `fun` is an anonymous function (that is, the type is `:local`), the following
-  additional keys are returned:
-
-    * `:pid` - PID of the process that originally created the function.
-
-    * `:index` - (integer) an index into the module function table.
-
-    * `:new_index` - (integer) an index into the module function table.
-
-    * `:new_uniq` - (binary) a unique value for this function. It's
-      calculated from the compiled code for the entire module.
-
-    * `:uniq` - (integer) a unique value for this function. This integer is
-      calculated from the compiled code for the entire module.
-
-  **Note**: this function must be used only for debugging purposes.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> fun = fn x -> x end
-      iex> info = Function.info(fun)
-      iex> Keyword.get(info, :arity)
-      1
-      iex> Keyword.get(info, :type)
-      :local
-
-      iex> fun = &String.length/1
-      iex> info = Function.info(fun)
-      iex> Keyword.get(info, :type)
-      :external
-      iex> Keyword.get(info, :name)
-      :length
-
-  """
-  @doc since: "1.7.0"
-  @spec info(fun) :: [{information, term}]
-  def info(fun), do: :erlang.fun_info(fun)
-
-  @doc """
-  Returns a specific information about the function.
-
-  The returned information is a two-element tuple in the shape of
-  `{info, value}`.
-
-  For any function, the information asked for can be any of the atoms
-  `:module`, `:name`, `:arity`, `:env`, or `:type`.
-
-  For anonymous functions, there is also information about any of the
-  atoms `:index`, `:new_index`, `:new_uniq`, `:uniq`, and `:pid`.
-  For a named function, the value of any of these items is always the
-  atom `:undefined`.
-
-  For more information on each of the possible returned values, see
-  `info/1`.
-
-  Inlined by the compiler.
-
-  ## Examples
-
-      iex> f = fn x -> x end
-      iex> Function.info(f, :arity)
-      {:arity, 1}
-      iex> Function.info(f, :type)
-      {:type, :local}
-
-      iex> fun = &String.length/1
-      iex> Function.info(fun, :name)
-      {:name, :length}
-      iex> Function.info(fun, :pid)
-      {:pid, :undefined}
-
-  """
-  @doc since: "1.7.0"
-  @spec info(fun, item) :: {item, term} when item: information
-  def info(fun, item), do: :erlang.fun_info(fun, item)
-
-  @doc """
-  Returns its input `value`. This function can be passed as an anonymous function
-  to transformation functions.
-
-  ## Examples
-
-      iex> Function.identity("Hello world!")
-      "Hello world!"
-
-      iex> 'abcdaabccc' |> Enum.sort() |> Enum.chunk_by(&Function.identity/1)
-      ['aaa', 'bb', 'cccc', 'd']
-
-      iex> Enum.group_by('abracadabra', &Function.identity/1)
-      %{97 => 'aaaaa', 98 => 'bb', 99 => 'c', 100 => 'd', 114 => 'rr'}
-
-      iex> Enum.map([1, 2, 3, 4], &Function.identity/1)
-      [1, 2, 3, 4]
-
-  """
-  @doc since: "1.10.0"
-  @spec identity(value) :: value when value: var
-  def identity(value), do: value
-end

lib/elixir/lib/gen_event/stream.ex

@@ -2,7 +2,9 @@ defmodule GenEvent.Stream do
   @moduledoc false
   defstruct manager: nil, timeout: :infinity
 
-  @type t :: %__MODULE__{manager: GenEvent.manager(), timeout: timeout}
+  @type t :: %__MODULE__{
+               manager: GenEvent.manager,
+               timeout: timeout}
 
   @doc false
   def init({_pid, _ref} = state) do
@@ -22,7 +24,6 @@ defmodule GenEvent.Stream do
   def handle_call(msg, _state) do
     # We do this to trick Dialyzer to not complain about non-local returns.
     reason = {:bad_call, msg}
-
     case :erlang.phash2(1, 1) do
       0 -> exit(reason)
       1 -> {:remove_handler, reason}
@@ -47,7 +48,7 @@ end
 
 defimpl Enumerable, for: GenEvent.Stream do
   def reduce(stream, acc, fun) do
-    start_fun = fn -> start(stream) end
+    start_fun = fn() -> start(stream) end
     next_fun = &next(stream, &1)
     stop_fun = &stop(stream, &1)
     Stream.resource(start_fun, next_fun, stop_fun).(acc, wrap_reducer(fun))
@@ -61,33 +62,26 @@ defimpl Enumerable, for: GenEvent.Stream do
     {:error, __MODULE__}
   end
 
-  def slice(_stream) do
-    {:error, __MODULE__}
-  end
-
   defp wrap_reducer(fun) do
     fn
       {:ack, manager, ref, event}, acc ->
-        send(manager, {ref, :ok})
+        send manager, {ref, :ok}
         fun.(event, acc)
-
       {:async, _manager, _ref, event}, acc ->
         fun.(event, acc)
-
       {:sync, manager, ref, event}, acc ->
         try do
           fun.(event, acc)
         after
-          send(manager, {ref, :ok})
+          send manager, {ref, :ok}
         end
     end
   end
 
   defp start(%{manager: manager} = stream) do
     try do
-      {:ok, {pid, ref}} =
-        :gen.call(manager, self(), {:add_process_handler, self(), self()}, :infinity)
-
+      {:ok, {pid, ref}} = :gen.call(manager, self(),
+                                    {:add_process_handler, self(), self()}, :infinity)
       mon_ref = Process.monitor(pid)
       {pid, ref, mon_ref}
     catch
@@ -135,7 +129,6 @@ defimpl Enumerable, for: GenEvent.Stream do
     case wait_for_handler_removal(pid, ref, mon_ref) do
       :ok ->
         flush_events(ref)
-
       {:error, reason} ->
         exit({reason, {__MODULE__, :stop, [stream, acc]}})
     end
@@ -144,7 +137,7 @@ defimpl Enumerable, for: GenEvent.Stream do
   # If we reach this branch, the handler was not removed yet,
   # so we trigger a request for doing so.
   defp stop(stream, {pid, ref, _} = acc) do
-    _ = :gen_event.delete_handler(pid, {pid, ref}, :shutdown)
+    _ = GenEvent.remove_handler(pid, {pid, ref}, :shutdown)
     stop(stream, {:removed, acc})
   end
 
@@ -153,7 +146,6 @@ defimpl Enumerable, for: GenEvent.Stream do
       {:gen_event_EXIT, {^pid, ^ref}, _reason} ->
         Process.demonitor(mon_ref, [:flush])
         :ok
-
       {:DOWN, ^mon_ref, _, _, reason} ->
         {:error, reason}
     end
@@ -161,8 +153,7 @@ defimpl Enumerable, for: GenEvent.Stream do
 
   defp flush_events(ref) do
     receive do
-      {_from, {_pid, ^ref}, {notify, _event}}
-      when notify in [:notify, :ack_notify, :sync_notify] ->
+      {_from, {_pid, ^ref}, {notify, _event}} when notify in [:notify, :ack_notify, :sync_notify] ->
         flush_events(ref)
     after
       0 -> :ok

lib/elixir/lib/hash_dict.ex

@@ -1,11 +1,11 @@
 defmodule HashDict do
   @moduledoc """
-  Tuple-based HashDict implementation.
+  WARNING: this module is deprecated.
 
-  This module is deprecated. Use the `Map` module instead.
+  Use the `Map` module instead.
   """
 
-  @moduledoc deprecated: "Use Map instead"
+  # TODO: Deprecate every function by 1.4
 
   use Dict
 
@@ -22,70 +22,58 @@ defmodule HashDict do
   @compile :inline_list_funcs
   @compile {:inline, key_hash: 1, key_mask: 1, key_shift: 1}
 
-  message = "Use maps and the Map module instead"
-
   @doc """
   Creates a new empty dict.
   """
-  @spec new :: Dict.t()
-  @deprecated message
+  @spec new :: Dict.t
   def new do
     %HashDict{}
   end
 
-  @deprecated message
   def put(%HashDict{root: root, size: size}, key, value) do
     {root, counter} = do_put(root, key, value, key_hash(key))
     %HashDict{root: root, size: size + counter}
   end
 
-  @deprecated message
   def update!(%HashDict{root: root, size: size} = dict, key, fun) when is_function(fun, 1) do
-    {root, counter} =
-      do_update(root, key, fn -> raise KeyError, key: key, term: dict end, fun, key_hash(key))
-
+    {root, counter} = do_update(root, key, fn -> raise KeyError, key: key, term: dict end,
+                                fun, key_hash(key))
     %HashDict{root: root, size: size + counter}
   end
 
-  @deprecated message
-  def update(%HashDict{root: root, size: size}, key, default, fun) when is_function(fun, 1) do
-    {root, counter} = do_update(root, key, fn -> default end, fun, key_hash(key))
+  def update(%HashDict{root: root, size: size}, key, initial, fun) when is_function(fun, 1) do
+    {root, counter} = do_update(root, key, fn -> initial end, fun, key_hash(key))
     %HashDict{root: root, size: size + counter}
   end
 
-  @deprecated message
   def fetch(%HashDict{root: root}, key) do
     do_fetch(root, key, key_hash(key))
   end
 
-  @deprecated message
   def delete(dict, key) do
     case dict_delete(dict, key) do
       {dict, _value} -> dict
-      :error -> dict
+      :error         -> dict
     end
   end
 
-  @deprecated message
   def pop(dict, key, default \\ nil) do
     case dict_delete(dict, key) do
       {dict, value} -> {value, dict}
-      :error -> {default, dict}
+      :error        -> {default, dict}
     end
   end
 
-  @deprecated message
   def size(%HashDict{size: size}) do
     size
   end
 
   @doc false
-  @deprecated message
   def reduce(%HashDict{root: root}, acc, fun) do
     do_reduce(root, acc, fun, @node_size, fn
       {:suspend, acc} -> {:suspended, acc, &{:done, elem(&1, 1)}}
-      {:halt, acc} -> {:halted, acc}
-      {:cont, acc} -> {:done, acc}
+      {:halt, acc}    -> {:halted, acc}
+      {:cont, acc}    -> {:done, acc}
     end)
   end
 
@@ -95,7 +83,7 @@ defmodule HashDict do
   def dict_delete(%HashDict{root: root, size: size}, key) do
     case do_delete(root, key, key_hash(key)) do
       {root, value} -> {%HashDict{root: root, size: size - 1}, value}
-      :error -> :error
+      :error        -> :error
     end
   end
 
@@ -103,92 +91,74 @@ defmodule HashDict do
 
   defp do_fetch(node, key, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
-      [^key | v] -> {:ok, v}
+      [^key | v]   -> {:ok, v}
       {^key, v, _} -> {:ok, v}
-      {_, _, n} -> do_fetch(n, key, key_shift(hash))
-      _ -> :error
+      {_, _, n}    -> do_fetch(n, key, key_shift(hash))
+      _            -> :error
     end
   end
 
   defp do_put(node, key, value, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         {put_elem(node, index, [key | value]), 1}
-
       [^key | _] ->
         {put_elem(node, index, [key | value]), 0}
-
       [k | v] ->
         n = put_elem(@node_template, key_mask(key_shift(hash)), [key | value])
         {put_elem(node, index, {k, v, n}), 1}
-
       {^key, _, n} ->
         {put_elem(node, index, {key, value, n}), 0}
-
       {k, v, n} ->
         {n, counter} = do_put(n, key, value, key_shift(hash))
         {put_elem(node, index, {k, v, n}), counter}
     end
   end
 
-  defp do_update(node, key, default, fun, hash) do
+  defp do_update(node, key, initial, fun, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
-        {put_elem(node, index, [key | default.()]), 1}
-
+        {put_elem(node, index, [key | initial.()]), 1}
       [^key | value] ->
         {put_elem(node, index, [key | fun.(value)]), 0}
-
       [k | v] ->
-        n = put_elem(@node_template, key_mask(key_shift(hash)), [key | default.()])
+        n = put_elem(@node_template, key_mask(key_shift(hash)), [key | initial.()])
         {put_elem(node, index, {k, v, n}), 1}
-
       {^key, value, n} ->
         {put_elem(node, index, {key, fun.(value), n}), 0}
-
       {k, v, n} ->
-        {n, counter} = do_update(n, key, default, fun, key_shift(hash))
+        {n, counter} = do_update(n, key, initial, fun, key_shift(hash))
         {put_elem(node, index, {k, v, n}), counter}
     end
   end
 
   defp do_delete(node, key, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         :error
-
       [^key | value] ->
         {put_elem(node, index, []), value}
-
       [_ | _] ->
         :error
-
       {^key, value, n} ->
         {put_elem(node, index, do_compact_node(n)), value}
-
       {k, v, n} ->
         case do_delete(n, key, key_shift(hash)) do
           {@node_template, value} ->
             {put_elem(node, index, [k | v]), value}
-
           {n, value} ->
             {put_elem(node, index, {k, v, n}), value}
-
           :error ->
             :error
         end
     end
   end
 
-  Enum.each(0..(@node_size - 1), fn index ->
+  Enum.each 0..(@node_size - 1), fn index ->
     defp do_compact_node(node) when elem(node, unquote(index)) != [] do
       case elem(node, unquote(index)) do
         [k | v] ->
@@ -196,12 +166,11 @@ defmodule HashDict do
             @node_template -> [k | v]
             n -> {k, v, n}
           end
-
         {k, v, n} ->
           {k, v, put_elem(node, unquote(index), do_compact_node(n))}
       end
     end
-  end)
+  end
 
   ## Dict reduce
 
@@ -226,12 +195,7 @@ defmodule HashDict do
   end
 
   defp do_reduce(node, acc, fun, count, next) when count > 0 do
-    do_reduce_each(
-      :erlang.element(count, node),
-      acc,
-      fun,
-      &do_reduce(node, &1, fun, count - 1, next)
-    )
+    do_reduce_each(:erlang.element(count, node), acc, fun, &do_reduce(node, &1, fun, count - 1, next))
   end
 
   defp do_reduce(_node, acc, _fun, 0, next) do
@@ -256,45 +220,19 @@ defmodule HashDict do
 end
 
 defimpl Enumerable, for: HashDict do
-  def reduce(dict, acc, fun) do
-    # Avoid warnings about HashDict being deprecated.
-    module = HashDict
-    module.reduce(dict, acc, fun)
-  end
-
-  def member?(dict, {key, value}) do
-    # Avoid warnings about HashDict being deprecated.
-    module = HashDict
-    {:ok, match?({:ok, ^value}, module.fetch(dict, key))}
-  end
-
-  def member?(_dict, _) do
-    {:ok, false}
-  end
-
-  def count(dict) do
-    # Avoid warnings about HashDict being deprecated.
-    module = HashDict
-    {:ok, module.size(dict)}
-  end
-
-  def slice(_dict) do
-    {:error, __MODULE__}
-  end
+  def reduce(dict, acc, fun),  do: HashDict.reduce(dict, acc, fun)
+  def member?(dict, {k, v}), do: {:ok, match?({:ok, ^v}, HashDict.fetch(dict, k))}
+  def member?(_dict, _),       do: {:ok, false}
+  def count(dict),             do: {:ok, HashDict.size(dict)}
 end
 
 defimpl Collectable, for: HashDict do
   def into(original) do
-    # Avoid warnings about HashDict being deprecated.
-    module = HashDict
-
-    collector_fun = fn
-      dict, {:cont, {key, value}} -> module.put(dict, key, value)
+    {original, fn
+      dict, {:cont, {k, v}} -> HashDict.put(dict, k, v)
       dict, :done -> dict
       _, :halt -> :ok
-    end
-
-    {original, collector_fun}
+    end}
   end
 end
 
@@ -302,8 +240,6 @@ defimpl Inspect, for: HashDict do
   import Inspect.Algebra
 
   def inspect(dict, opts) do
-    # Avoid warnings about HashDict being deprecated.
-    module = HashDict
-    concat(["#HashDict<", Inspect.List.inspect(module.to_list(dict), opts), ">"])
+    concat ["#HashDict<", Inspect.List.inspect(HashDict.to_list(dict), opts), ">"]
   end
 end

lib/elixir/lib/hash_set.ex

@@ -1,19 +1,17 @@
 defmodule HashSet do
   @moduledoc """
-  Tuple-based HashSet implementation.
+  WARNING: this module is deprecated.
 
-  This module is deprecated. Use the `MapSet` module instead.
+  Use the `MapSet` module instead.
   """
 
-  @moduledoc deprecated: "Use MapSet instead"
+  # TODO: Deprecate every function by 1.4
 
   @node_bitmap 0b111
   @node_shift 3
   @node_size 8
   @node_template :erlang.make_tuple(@node_size, [])
 
-  message = "Use the MapSet module instead"
-
   @opaque t :: %__MODULE__{size: non_neg_integer, root: term}
   @doc false
   defstruct size: 0, root: @node_template
@@ -22,85 +20,71 @@ defmodule HashSet do
   @compile :inline_list_funcs
   @compile {:inline, key_hash: 1, key_mask: 1, key_shift: 1}
 
-  @deprecated message
-  @spec new :: Set.t()
+  @spec new :: Set.t
   def new do
     %HashSet{}
   end
 
-  @deprecated message
   def union(%HashSet{size: size1} = set1, %HashSet{size: size2} = set2) when size1 <= size2 do
-    set_fold(set1, set2, fn v, acc -> put(acc, v) end)
+    set_fold set1, set2, fn v, acc -> put(acc, v) end
   end
 
-  @deprecated message
   def union(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold(set2, set1, fn v, acc -> put(acc, v) end)
+    set_fold set2, set1, fn v, acc -> put(acc, v) end
   end
 
-  @deprecated message
   def intersection(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold(set1, %HashSet{}, fn v, acc ->
+    set_fold set1, %HashSet{}, fn v, acc ->
       if member?(set2, v), do: put(acc, v), else: acc
-    end)
-  end
-
-  @deprecated message
-  def difference(%HashSet{} = set1, %HashSet{} = set2) do
-    set_fold(set2, set1, fn v, acc -> delete(acc, v) end)
-  end
-
-  @deprecated message
-  def to_list(set) do
-    set_fold(set, [], &[&1 | &2]) |> :lists.reverse()
-  end
-
-  @deprecated message
-  def equal?(%HashSet{size: size1} = set1, %HashSet{size: size2} = set2) do
-    case size1 do
-      ^size2 -> subset?(set1, set2)
-      _ -> false
     end
   end
 
-  @deprecated message
+  def difference(%HashSet{} = set1, %HashSet{} = set2) do
+    set_fold set2, set1, fn v, acc -> delete(acc, v) end
+  end
+
+  def to_list(set) do
+    set_fold(set, [], &[&1 | &2]) |> :lists.reverse
+  end
+
+  def equal?(%HashSet{size: size1} = set1, %HashSet{size: size2} = set2) do
+    case size1 do
+      ^size2 -> subset?(set1, set2)
+      _      -> false
+    end
+  end
+
   def subset?(%HashSet{} = set1, %HashSet{} = set2) do
     reduce(set1, {:cont, true}, fn member, acc ->
       case member?(set2, member) do
         true -> {:cont, acc}
-        _ -> {:halt, false}
+        _    -> {:halt, false}
       end
-    end)
-    |> elem(1)
+    end) |> elem(1)
   end
 
-  @deprecated message
   def disjoint?(%HashSet{} = set1, %HashSet{} = set2) do
     reduce(set2, {:cont, true}, fn member, acc ->
       case member?(set1, member) do
         false -> {:cont, acc}
-        _ -> {:halt, false}
+        _     -> {:halt, false}
       end
-    end)
-    |> elem(1)
+    end) |> elem(1)
   end
 
-  @deprecated message
   def member?(%HashSet{root: root}, term) do
     do_member?(root, term, key_hash(term))
   end
 
-  @deprecated message
   def put(%HashSet{root: root, size: size}, term) do
     {root, counter} = do_put(root, term, key_hash(term))
     %HashSet{root: root, size: size + counter}
   end
 
-  @deprecated message
   def delete(%HashSet{root: root, size: size} = set, term) do
     case do_delete(root, term, key_hash(term)) do
       {:ok, root} -> %HashSet{root: root, size: size - 1}
-      :error -> set
+      :error      -> set
     end
   end
 
@@ -108,12 +92,11 @@ defmodule HashSet do
   def reduce(%HashSet{root: root}, acc, fun) do
     do_reduce(root, acc, fun, @node_size, fn
       {:suspend, acc} -> {:suspended, acc, &{:done, elem(&1, 1)}}
-      {:halt, acc} -> {:halted, acc}
-      {:cont, acc} -> {:done, acc}
+      {:halt, acc}    -> {:halted, acc}
+      {:cont, acc}    -> {:done, acc}
     end)
   end
 
-  @deprecated message
   def size(%HashSet{size: size}) do
     size
   end
@@ -128,29 +111,24 @@ defmodule HashSet do
 
   defp do_member?(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
-      [] -> false
+      []          -> false
       [^term | _] -> true
-      [_] -> false
-      [_ | n] -> do_member?(n, term, key_shift(hash))
+      [_]         -> false
+      [_ | n]     -> do_member?(n, term, key_shift(hash))
     end
   end
 
   defp do_put(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         {put_elem(node, index, [term]), 1}
-
       [^term | _] ->
         {node, 0}
-
       [t] ->
         n = put_elem(@node_template, key_mask(key_shift(hash)), [term])
         {put_elem(node, index, [t | n]), 1}
-
       [t | n] ->
         {n, counter} = do_put(n, term, key_shift(hash))
         {put_elem(node, index, [t | n]), counter}
@@ -159,35 +137,28 @@ defmodule HashSet do
 
   defp do_delete(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         :error
-
       [^term] ->
         {:ok, put_elem(node, index, [])}
-
       [_] ->
         :error
-
       [^term | n] ->
         {:ok, put_elem(node, index, do_compact_node(n))}
-
       [t | n] ->
         case do_delete(n, term, key_shift(hash)) do
           {:ok, @node_template} ->
             {:ok, put_elem(node, index, [t])}
-
           {:ok, n} ->
             {:ok, put_elem(node, index, [t | n])}
-
           :error ->
             :error
         end
     end
   end
 
-  Enum.each(0..(@node_size - 1), fn index ->
+  Enum.each 0..(@node_size - 1), fn index ->
     defp do_compact_node(node) when elem(node, unquote(index)) != [] do
       case elem(node, unquote(index)) do
         [t] ->
@@ -195,17 +166,16 @@ defmodule HashSet do
             @node_template -> [t]
             n -> [t | n]
           end
-
         [t | n] ->
           [t | put_elem(node, unquote(index), do_compact_node(n))]
       end
     end
-  end)
+  end
 
   ## Set fold
 
-  defp do_fold_each([], acc, _fun), do: acc
-  defp do_fold_each([t], acc, fun), do: fun.(t, acc)
+  defp do_fold_each([], acc, _fun),     do: acc
+  defp do_fold_each([t], acc, fun),     do: fun.(t, acc)
   defp do_fold_each([t | n], acc, fun), do: do_fold(n, fun.(t, acc), fun, @node_size)
 
   defp do_fold(node, acc, fun, count) when count > 0 do
@@ -240,12 +210,7 @@ defmodule HashSet do
   end
 
   defp do_reduce(node, acc, fun, count, next) when count > 0 do
-    do_reduce_each(
-      :erlang.element(count, node),
-      acc,
-      fun,
-      &do_reduce(node, &1, fun, count - 1, next)
-    )
+    do_reduce_each(:erlang.element(count, node), acc, fun, &do_reduce(node, &1, fun, count - 1, next))
   end
 
   defp do_reduce(_node, acc, _fun, 0, next) do
@@ -270,41 +235,18 @@ defmodule HashSet do
 end
 
 defimpl Enumerable, for: HashSet do
-  def reduce(set, acc, fun) do
-    # Avoid warnings about HashSet being deprecated.
-    module = HashSet
-    module.reduce(set, acc, fun)
-  end
-
-  def member?(set, term) do
-    # Avoid warnings about HashSet being deprecated.
-    module = HashSet
-    {:ok, module.member?(set, term)}
-  end
-
-  def count(set) do
-    # Avoid warnings about HashSet being deprecated.
-    module = HashSet
-    {:ok, module.size(set)}
-  end
-
-  def slice(_set) do
-    {:error, __MODULE__}
-  end
+  def reduce(set, acc, fun), do: HashSet.reduce(set, acc, fun)
+  def member?(set, v),       do: {:ok, HashSet.member?(set, v)}
+  def count(set),            do: {:ok, HashSet.size(set)}
 end
 
 defimpl Collectable, for: HashSet do
   def into(original) do
-    # Avoid warnings about HashSet being deprecated.
-    module = HashSet
-
-    collector_fun = fn
-      set, {:cont, term} -> module.put(set, term)
+    {original, fn
+      set, {:cont, x} -> HashSet.put(set, x)
       set, :done -> set
       _, :halt -> :ok
-    end
-
-    {original, collector_fun}
+    end}
   end
 end
 
@@ -312,8 +254,6 @@ defimpl Inspect, for: HashSet do
   import Inspect.Algebra
 
   def inspect(set, opts) do
-    # Avoid warnings about HashSet being deprecated.
-    module = HashSet
-    concat(["#HashSet<", Inspect.List.inspect(module.to_list(set), opts), ">"])
+    concat ["#HashSet<", Inspect.List.inspect(HashSet.to_list(set), opts), ">"]
   end
 end

lib/elixir/lib/inspect.ex

@@ -1,47 +1,42 @@
 import Kernel, except: [inspect: 1]
 import Inspect.Algebra
 
-alias Code.Identifier
-
 defprotocol Inspect do
   @moduledoc """
-  The `Inspect` protocol converts an Elixir data structure into an
-  algebra document.
-
-  This documentation refers to implementing the `Inspect` protocol
-  for your own data structures. To learn more about using inspect,
-  see `Kernel.inspect/2` and `IO.inspect/2`.
+  The `Inspect` protocol is responsible for converting any Elixir
+  data structure into an algebra document. This document is then
+  formatted, either in pretty printing format or a regular one.
 
   The `inspect/2` function receives the entity to be inspected
   followed by the inspecting options, represented by the struct
-  `Inspect.Opts`. Building of the algebra document is done with
-  `Inspect.Algebra`.
+  `Inspect.Opts`.
+
+  Inspection is done using the functions available in `Inspect.Algebra`.
 
   ## Examples
 
   Many times, inspecting a structure can be implemented in function
-  of existing entities. For example, here is `MapSet`'s `inspect/2`
+  of existing entities. For example, here is `MapSet`'s `inspect`
   implementation:
 
       defimpl Inspect, for: MapSet do
         import Inspect.Algebra
 
-        def inspect(map_set, opts) do
-          concat(["#MapSet<", to_doc(MapSet.to_list(map_set), opts), ">"])
+        def inspect(dict, opts) do
+          concat ["#MapSet<", to_doc(MapSet.to_list(dict), opts), ">"]
         end
       end
 
-  The [`concat/1`](`Inspect.Algebra.concat/1`) function comes from
-  `Inspect.Algebra` and it concatenates algebra documents together.
-  In the example above it is concatenating the string `"#MapSet<"`,
-  the document returned by `Inspect.Algebra.to_doc/2`, and the final
-  string `">"`. We prefix the module name `#` to denote the inspect
-  presentation is not actually valid Elixir syntax.
+  The `concat/1` function comes from `Inspect.Algebra` and it
+  concatenates algebra documents together. In the example above,
+  it is concatenating the string `"MapSet<"` (all strings are
+  valid algebra documents that keep their formatting when pretty
+  printed), the document returned by `Inspect.Algebra.to_doc/2` and the
+  other string `">"`.
 
-  Finally, note strings themselves are valid algebra documents that
-  keep their formatting when pretty printed. This means your `Inspect`
-  implementation may simply return a string, although that will devoid
-  it of any pretty-printing.
+  Since regular strings are valid entities in an algebra document,
+  an implementation of inspect may simply return a string,
+  although that will devoid it of any pretty-printing.
 
   ## Error handling
 
@@ -49,44 +44,17 @@ defprotocol Inspect do
   Elixir will raise an `ArgumentError` error and will automatically fall back
   to a raw representation for printing the structure.
 
-  You can however access the underlying error by invoking the `Inspect`
-  implementation directly. For example, to test `Inspect.MapSet` above,
+  You can however access the underlying error by invoking the Inspect
+  implementation directly. For example, to test Inspect.MapSet above,
   you can invoke it as:
 
-      Inspect.MapSet.inspect(MapSet.new(), %Inspect.Opts{})
-
-  ## Deriving
-
-  The `Inspect` protocol can be derived to hide certain fields from
-  structs, so they don't show up in logs, inspects and similar. This
-  is especially useful for fields containing private information.
-
-  The options `:only` and `:except` can be used with `@derive` to
-  specify which fields should and should not appear in the
-  algebra document:
-
-      defmodule User do
-        @derive {Inspect, only: [:id, :name]}
-        defstruct [:id, :name, :address]
-      end
-
-      inspect(%User{id: 1, name: "Homer", address: "742 Evergreen Terrace"})
-      #=> #User<id: 1, name: "Homer", ...>
+      Inspect.MapSet.inspect(MapSet.new, %Inspect.Opts{})
 
   """
 
   # Handle structs in Any
   @fallback_to_any true
 
-  @doc """
-  Converts `term` into an algebra document.
-
-  This function shouldn't be invoked directly, unless when implementing
-  a custom `inspect_fun` to be given to `Inspect.Opts`. Everywhere else,
-  `Inspect.Algebra.to_doc/2` should be preferred as it handles structs
-  and exceptions.
-  """
-  @spec inspect(t, Inspect.Opts.t()) :: Inspect.Algebra.t()
   def inspect(term, opts)
 end
 
@@ -94,27 +62,93 @@ defimpl Inspect, for: Atom do
   require Macro
 
   def inspect(atom, opts) do
-    color(Identifier.inspect_as_atom(atom), color_key(atom), opts)
+    color(inspect(atom), color_key(atom), opts)
   end
 
   defp color_key(atom) when is_boolean(atom), do: :boolean
-  defp color_key(nil), do: nil
+  defp color_key(nil), do: :nil
   defp color_key(_), do: :atom
+
+  def inspect(false),  do: "false"
+  def inspect(true),   do: "true"
+  def inspect(nil),    do: "nil"
+  def inspect(:""),    do: ":\"\""
+
+  def inspect(atom) do
+    binary = Atom.to_string(atom)
+
+    cond do
+      valid_ref_identifier?(binary) ->
+        if only_elixir?(binary) do
+          binary
+        else
+          "Elixir." <> rest = binary
+          rest
+        end
+      valid_atom_identifier?(binary) ->
+        ":" <> binary
+      atom in [:%{}, :{}, :<<>>, :..., :%] ->
+        ":" <> binary
+      atom in Macro.binary_ops or atom in Macro.unary_ops ->
+        ":" <> binary
+      true ->
+        IO.iodata_to_binary [?:, ?", Inspect.BitString.escape(binary, ?"), ?"]
+    end
+  end
+
+  defp only_elixir?("Elixir." <> rest), do: only_elixir?(rest)
+  defp only_elixir?("Elixir"), do: true
+  defp only_elixir?(_), do: false
+
+  # Detect if atom is an atom alias (Elixir.Foo.Bar.Baz)
+
+  defp valid_ref_identifier?("Elixir" <> rest) do
+    valid_ref_piece?(rest)
+  end
+
+  defp valid_ref_identifier?(_), do: false
+
+  defp valid_ref_piece?(<<?., h, t::binary>>) when h in ?A..?Z do
+    valid_ref_piece? valid_identifier?(t)
+  end
+
+  defp valid_ref_piece?(<<>>), do: true
+  defp valid_ref_piece?(_),    do: false
+
+  # Detect if atom
+
+  defp valid_atom_identifier?(<<h, t::binary>>) when h in ?a..?z or h in ?A..?Z or h == ?_ do
+    valid_atom_piece?(t)
+  end
+
+  defp valid_atom_identifier?(_), do: false
+
+  defp valid_atom_piece?(t) do
+    case valid_identifier?(t) do
+      <<>>              -> true
+      <<??>>            -> true
+      <<?!>>            -> true
+      <<?@, t::binary>> -> valid_atom_piece?(t)
+      _                 -> false
+    end
+  end
+
+  defp valid_identifier?(<<h, t::binary>>)
+      when h in ?a..?z
+      when h in ?A..?Z
+      when h in ?0..?9
+      when h == ?_ do
+    valid_identifier? t
+  end
+
+  defp valid_identifier?(other), do: other
 end
 
 defimpl Inspect, for: BitString do
-  def inspect(term, opts) when is_binary(term) do
-    %Inspect.Opts{binaries: bins, base: base, printable_limit: printable_limit} = opts
-
-    if base == :decimal and
-         (bins == :as_strings or (bins == :infer and String.printable?(term, printable_limit))) do
-      inspected =
-        case Identifier.escape(term, ?", printable_limit) do
-          {escaped, ""} -> [?", escaped, ?"]
-          {escaped, _} -> [?", escaped, ?", " <> ..."]
-        end
-
-      color(IO.iodata_to_binary(inspected), :string, opts)
+  def inspect(term, %Inspect.Opts{binaries: bins, base: base} = opts) when is_binary(term) do
+    if base == :decimal and (bins == :as_strings or (bins == :infer and String.printable?(term))) do
+      inspected = IO.iodata_to_binary([?", escape(term, ?"), ?"])
+      color(inspected, :string, opts)
     else
       inspect_bitstring(term, opts)
     end
@@ -124,6 +158,88 @@ defimpl Inspect, for: BitString do
     inspect_bitstring(term, opts)
   end
 
+  ## Escaping
+
+  @doc false
+  def escape(other, char) do
+    escape(other, char, [])
+  end
+
+  defp escape(<<char, t::binary>>, char, acc) do
+    escape(t, char, [acc | [?\\, char]])
+  end
+  defp escape(<<?#, ?{, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\\#{'])
+  end
+  defp escape(<<?\a, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\a'])
+  end
+  defp escape(<<?\b, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\b'])
+  end
+  defp escape(<<?\d, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\d'])
+  end
+  defp escape(<<?\e, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\e'])
+  end
+  defp escape(<<?\f, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\f'])
+  end
+  defp escape(<<?\n, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\n'])
+  end
+  defp escape(<<?\r, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\r'])
+  end
+  defp escape(<<?\\, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\\\'])
+  end
+  defp escape(<<?\t, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\t'])
+  end
+  defp escape(<<?\v, t::binary>>, char, acc) do
+    escape(t, char, [acc | '\\v'])
+  end
+  defp escape(<<h::utf8, t::binary>>, char, acc)
+       when h in 0x20..0x7E
+       when h in 0xA0..0xD7FF
+       when h in 0xE000..0xFFFD
+       when h in 0x10000..0x10FFFF do
+    escape(t, char, [acc | <<h::utf8>>])
+  end
+  defp escape(<<h, t::binary>>, char, acc) do
+    escape(t, char, [acc | escape_char(h)])
+  end
+  defp escape(<<>>, _char, acc), do: acc
+
+  @doc false
+  # Also used by Regex
+  def escape_char(0) do
+    '\\0'
+  end
+
+  def escape_char(char) when char < 0x100 do
+    <<a::4, b::4>> = <<char::8>>
+    ['\\x', to_hex(a), to_hex(b)]
+  end
+
+  def escape_char(char) when char < 0x10000 do
+    <<a::4, b::4, c::4, d::4>> = <<char::16>>
+    ['\\x{', to_hex(a), to_hex(b), to_hex(c), to_hex(d), ?}]
+  end
+
+  def escape_char(char) when char < 0x1000000 do
+    <<a::4, b::4, c::4, d::4, e::4, f::4>> = <<char::24>>
+    ['\\x{', to_hex(a), to_hex(b), to_hex(c),
+             to_hex(d), to_hex(e), to_hex(f), ?}]
+  end
+
+  defp to_hex(c) when c in 0..9, do: ?0+c
+  defp to_hex(c) when c in 10..15, do: ?A+c-10
+
+  ## Bitstrings
+
   defp inspect_bitstring("", opts) do
     color("<<>>", :binary, opts)
   end
@@ -131,8 +247,7 @@ defimpl Inspect, for: BitString do
   defp inspect_bitstring(bitstring, opts) do
     left = color("<<", :binary, opts)
     right = color(">>", :binary, opts)
-    inner = each_bit(bitstring, opts.limit, opts)
-    group(concat(concat(left, nest(inner, 2)), right))
+    nest surround(left, each_bit(bitstring, opts.limit, opts), right), 1
   end
 
   defp each_bit(_, 0, _) do
@@ -148,21 +263,18 @@ defimpl Inspect, for: BitString do
   end
 
   defp each_bit(<<h, t::bitstring>>, counter, opts) do
-    flex_glue(
-      concat(Inspect.Integer.inspect(h, opts), ","),
-      each_bit(t, decrement(counter), opts)
-    )
+    glue(concat(Inspect.Integer.inspect(h, opts), ","),
+         each_bit(t, decrement(counter), opts))
   end
 
   defp each_bit(bitstring, _counter, opts) do
     size = bit_size(bitstring)
     <<h::size(size)>> = bitstring
-    concat(Inspect.Integer.inspect(h, opts), "::size(" <> Integer.to_string(size) <> ")")
+    Inspect.Integer.inspect(h, opts) <> "::size(" <> Integer.to_string(size) <> ")"
   end
 
-  @compile {:inline, decrement: 1}
   defp decrement(:infinity), do: :infinity
-  defp decrement(counter), do: counter - 1
+  defp decrement(counter),   do: counter - 1
 end
 
 defimpl Inspect, for: List do
@@ -170,28 +282,14 @@ defimpl Inspect, for: List do
     color("[]", :list, opts)
   end
 
-  # TODO: Remove :char_list and :as_char_lists handling on v2.0
-  def inspect(term, opts) do
-    %Inspect.Opts{
-      charlists: lists,
-      char_lists: lists_deprecated,
-      printable_limit: printable_limit
-    } = opts
-
+  # TODO: Deprecate :char_lists and :as_char_lists keys in v1.5
+  def inspect(term, %Inspect.Opts{charlists: lists, char_lists: lists_deprecated} = opts) do
     lists =
       if lists == :infer and lists_deprecated != :infer do
         case lists_deprecated do
           :as_char_lists ->
-            IO.warn(
-              "the :char_lists inspect option and its :as_char_lists " <>
-                "value are deprecated, use the :charlists option and its " <>
-                ":as_charlists value instead"
-            )
-
             :as_charlists
-
           _ ->
-            IO.warn("the :char_lists inspect option is deprecated, use :charlists instead")
             lists_deprecated
         end
       else
@@ -203,27 +301,19 @@ defimpl Inspect, for: List do
     close = color("]", :list, opts)
 
     cond do
-      lists == :as_charlists or (lists == :infer and List.ascii_printable?(term, printable_limit)) ->
-        inspected =
-          case Identifier.escape(IO.chardata_to_string(term), ?', printable_limit) do
-            {escaped, ""} -> [?', escaped, ?']
-            {escaped, _} -> [?', escaped, ?', " ++ ..."]
-          end
-
-        IO.iodata_to_binary(inspected)
-
+      lists == :as_charlists or (lists == :infer and printable?(term)) ->
+        IO.iodata_to_binary [?', Inspect.BitString.escape(IO.chardata_to_string(term), ?'), ?']
       keyword?(term) ->
-        container_doc(open, term, close, opts, &keyword/2, separator: sep, break: :strict)
-
+        surround_many(open, term, close, opts, &keyword/2, sep)
       true ->
-        container_doc(open, term, close, opts, &to_doc/2, separator: sep)
+        surround_many(open, term, close, opts, &to_doc/2, sep)
     end
   end
 
   @doc false
   def keyword({key, value}, opts) do
-    key = color(Identifier.inspect_as_key(key), :atom, opts)
-    concat(key, concat(" ", to_doc(value, opts)))
+    key = color(key_to_binary(key) <> ": ", :atom, opts)
+    concat(key, to_doc(value, opts))
   end
 
   @doc false
@@ -234,8 +324,30 @@ defimpl Inspect, for: List do
     end
   end
 
-  def keyword?([]), do: true
+  def keyword?([]),     do: true
   def keyword?(_other), do: false
+
+  @doc false
+  def printable?([char | rest]) when char in 32..126, do: printable?(rest)
+  def printable?([?\n | rest]), do: printable?(rest)
+  def printable?([?\r | rest]), do: printable?(rest)
+  def printable?([?\t | rest]), do: printable?(rest)
+  def printable?([?\v | rest]), do: printable?(rest)
+  def printable?([?\b | rest]), do: printable?(rest)
+  def printable?([?\f | rest]), do: printable?(rest)
+  def printable?([?\e | rest]), do: printable?(rest)
+  def printable?([?\a | rest]), do: printable?(rest)
+  def printable?([]), do: true
+  def printable?(_), do: false
+
+  ## Private
+
+  defp key_to_binary(key) do
+    case Inspect.Atom.inspect(key) do
+      ":" <> right -> right
+      other -> other
+    end
+  end
 end
 
 defimpl Inspect, for: Tuple do
@@ -243,35 +355,36 @@ defimpl Inspect, for: Tuple do
     open = color("{", :tuple, opts)
     sep = color(",", :tuple, opts)
     close = color("}", :tuple, opts)
-    container_opts = [separator: sep, break: :flex]
-    container_doc(open, Tuple.to_list(tuple), close, opts, &to_doc/2, container_opts)
+    surround_many(open, Tuple.to_list(tuple), close, opts, &to_doc/2, sep)
   end
 end
 
 defimpl Inspect, for: Map do
   def inspect(map, opts) do
-    inspect(map, "", opts)
+    nest inspect(map, "", opts), 1
   end
 
   def inspect(map, name, opts) do
-    map = Map.to_list(map)
+    map = :maps.to_list(map)
     open = color("%" <> name <> "{", :map, opts)
     sep = color(",", :map, opts)
     close = color("}", :map, opts)
-    container_doc(open, map, close, opts, traverse_fun(map, opts), separator: sep, break: :strict)
+    surround_many(open, map, close, opts, traverse_fun(map), sep)
   end
 
-  defp traverse_fun(list, opts) do
+  defp traverse_fun(list) do
     if Inspect.List.keyword?(list) do
       &Inspect.List.keyword/2
     else
-      sep = color(" => ", :map, opts)
-      &to_map(&1, &2, sep)
+      &to_map/2
     end
   end
 
-  defp to_map({key, value}, opts, sep) do
-    concat(concat(to_doc(key, opts), sep), to_doc(value, opts))
+  defp to_map({key, value}, opts) do
+    concat(
+      concat(to_doc(key, opts), " => "),
+      to_doc(value, opts)
+    )
   end
 end
 
@@ -283,27 +396,20 @@ defimpl Inspect, for: Integer do
 
   defp base_to_value(base) do
     case base do
-      :binary -> 2
+      :binary  -> 2
       :decimal -> 10
-      :octal -> 8
-      :hex -> 16
+      :octal   -> 8
+      :hex     -> 16
     end
   end
 
   defp prepend_prefix(value, :decimal), do: value
-
-  defp prepend_prefix(<<?-, value::binary>>, base) do
-    "-" <> prepend_prefix(value, base)
-  end
-
   defp prepend_prefix(value, base) do
-    prefix =
-      case base do
-        :binary -> "0b"
-        :octal -> "0o"
-        :hex -> "0x"
-      end
-
+    prefix = case base do
+      :binary -> "0b"
+      :octal  -> "0o"
+      :hex    -> "0x"
+    end
     prefix <> value
   end
 end
@@ -317,57 +423,77 @@ end
 
 defimpl Inspect, for: Regex do
   def inspect(regex, opts) do
-    {escaped, _} =
-      regex.source
-      |> normalize(<<>>)
-      |> Identifier.escape(?/, :infinity, &escape_map/1)
-
-    source = IO.iodata_to_binary(['~r/', escaped, ?/, regex.opts])
+    source = IO.iodata_to_binary(['~r/', escape(regex.source, ?/), ?/, regex.opts])
     color(source, :regex, opts)
   end
 
-  defp normalize(<<?\\, ?\\, rest::binary>>, acc), do: normalize(rest, <<acc::binary, ?\\, ?\\>>)
-  defp normalize(<<?\\, ?/, rest::binary>>, acc), do: normalize(rest, <<acc::binary, ?/>>)
-  defp normalize(<<char, rest::binary>>, acc), do: normalize(rest, <<acc::binary, char>>)
-  defp normalize(<<>>, acc), do: acc
+  defp escape(bin, term),
+    do: escape(bin, [], term)
 
-  defp escape_map(?\a), do: '\\a'
-  defp escape_map(?\f), do: '\\f'
-  defp escape_map(?\n), do: '\\n'
-  defp escape_map(?\r), do: '\\r'
-  defp escape_map(?\t), do: '\\t'
-  defp escape_map(?\v), do: '\\v'
-  defp escape_map(_), do: false
+  defp escape(<<?\\, term>> <> rest, buf, term),
+    do: escape(rest, [buf | [?\\, term]], term)
+
+  defp escape(<<term>> <> rest, buf, term),
+    do: escape(rest, [buf | [?\\, term]], term)
+
+  # The list of characters is from 'String.printable?' implementation
+  # minus characters treated specially by regex: \s, \d, \b, \e
+
+  defp escape(<<?\n>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\n'], term)
+
+  defp escape(<<?\r>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\r'], term)
+
+  defp escape(<<?\t>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\t'], term)
+
+  defp escape(<<?\v>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\v'], term)
+
+  defp escape(<<?\f>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\f'], term)
+
+  defp escape(<<?\a>> <> rest, buf, term),
+    do: escape(rest, [buf | '\\a'], term)
+
+  defp escape(<<char::utf8, rest::binary>>, buf, term)
+       when char in 0x20..0x7E
+       when char in 0xA0..0xD7FF
+       when char in 0xE000..0xFFFD
+       when char in 0x10000..0x10FFFF,
+    do: escape(rest, [buf | <<char::utf8>>], term)
+
+  defp escape(<<char, rest::binary>>, buf, term),
+    do: escape(rest, [buf | Inspect.BitString.escape_char(char)], term)
+
+  defp escape(<<>>, buf, _), do: buf
 end
 
 defimpl Inspect, for: Function do
   def inspect(function, _opts) do
-    fun_info = Function.info(function)
+    fun_info = :erlang.fun_info(function)
     mod = fun_info[:module]
-    name = fun_info[:name]
 
-    cond do
-      fun_info[:type] == :external and fun_info[:env] == [] ->
-        inspected_as_atom = Identifier.inspect_as_atom(mod)
-        inspected_as_function = Identifier.inspect_as_function(name)
-        "&#{inspected_as_atom}.#{inspected_as_function}/#{fun_info[:arity]}"
-
-      match?('elixir_compiler_' ++ _, Atom.to_charlist(mod)) ->
-        if function_exported?(mod, :__RELATIVE__, 0) do
-          "#Function<#{uniq(fun_info)} in file:#{mod.__RELATIVE__}>"
-        else
+    if fun_info[:type] == :external and fun_info[:env] == [] do
+      "&#{Inspect.Atom.inspect(mod)}.#{fun_info[:name]}/#{fun_info[:arity]}"
+    else
+      case Atom.to_charlist(mod) do
+        'elixir_compiler_' ++ _ ->
+          if function_exported?(mod, :__RELATIVE__, 0) do
+            "#Function<#{uniq(fun_info)} in file:#{mod.__RELATIVE__}>"
+          else
+            default_inspect(mod, fun_info)
+          end
+        _ ->
           default_inspect(mod, fun_info)
-        end
-
-      true ->
-        default_inspect(mod, fun_info)
+      end
     end
   end
 
   defp default_inspect(mod, fun_info) do
-    inspected_as_atom = Identifier.inspect_as_atom(mod)
-    extracted_name = extract_name(fun_info[:name])
-    "#Function<#{uniq(fun_info)}/#{fun_info[:arity]} in #{inspected_as_atom}#{extracted_name}>"
+    "#Function<#{uniq(fun_info)}/#{fun_info[:arity]} in " <>
+      "#{Inspect.Atom.inspect(mod)}#{extract_name(fun_info[:name])}>"
   end
 
   defp extract_name([]) do
@@ -375,17 +501,16 @@ defimpl Inspect, for: Function do
   end
 
   defp extract_name(name) do
-    case Identifier.extract_anonymous_fun_parent(name) do
-      {name, arity} ->
-        "." <> Identifier.inspect_as_function(name) <> "/" <> arity
-
-      :error ->
-        "." <> Identifier.inspect_as_function(name)
+    name = Atom.to_string(name)
+    case :binary.split(name, "-", [:global]) do
+      ["", name | _] -> "." <> name
+      _ -> "." <> name
     end
   end
 
   defp uniq(fun_info) do
-    Integer.to_string(fun_info[:new_index]) <> "." <> Integer.to_string(fun_info[:uniq])
+    Integer.to_string(fun_info[:new_index]) <> "." <>
+      Integer.to_string(fun_info[:uniq])
   end
 end
 
@@ -409,82 +534,20 @@ defimpl Inspect, for: Reference do
 end
 
 defimpl Inspect, for: Any do
-  defmacro __deriving__(module, struct, options) do
-    fields = Map.keys(struct) -- [:__exception__, :__struct__]
-    only = Keyword.get(options, :only, fields)
-    except = Keyword.get(options, :except, [])
-
-    filtered_fields =
-      fields
-      |> Enum.reject(&(&1 in except))
-      |> Enum.filter(&(&1 in only))
-
-    inspect_module =
-      if fields == only and except == [] do
-        Inspect.Map
-      else
-        Inspect.Any
-      end
-
-    quote do
-      defimpl Inspect, for: unquote(module) do
-        def inspect(var!(struct), var!(opts)) do
-          var!(map) = Map.take(var!(struct), unquote(filtered_fields))
-          var!(name) = Identifier.inspect_as_atom(unquote(module))
-          unquote(inspect_module).inspect(var!(map), var!(name), var!(opts))
-        end
-      end
-    end
-  end
-
-  def inspect(%module{} = struct, opts) do
+  def inspect(%{__struct__: struct} = map, opts) do
     try do
-      module.__struct__()
+      struct.__struct__
     rescue
-      _ -> Inspect.Map.inspect(struct, opts)
+      _ -> Inspect.Map.inspect(map, opts)
     else
       dunder ->
-        if Map.keys(dunder) == Map.keys(struct) do
-          pruned = Map.drop(struct, [:__struct__, :__exception__])
-          Inspect.Map.inspect(pruned, Identifier.inspect_as_atom(module), opts)
+        if :maps.keys(dunder) == :maps.keys(map) do
+          pruned = :maps.remove(:__exception__, :maps.remove(:__struct__, map))
+          colorless_opts = %{opts | syntax_colors: []}
+          Inspect.Map.inspect(pruned, Inspect.Atom.inspect(struct, colorless_opts), opts)
         else
-          Inspect.Map.inspect(struct, opts)
+          Inspect.Map.inspect(map, opts)
         end
     end
   end
-
-  def inspect(map, name, opts) do
-    map = Map.to_list(map) ++ [:...]
-    open = color("#" <> name <> "<", :map, opts)
-    sep = color(",", :map, opts)
-    close = color(">", :map, opts)
-
-    fun = fn
-      {key, value}, opts -> Inspect.List.keyword({key, value}, opts)
-      :..., _opts -> "..."
-    end
-
-    container_doc(open, map, close, opts, fun, separator: sep, break: :strict)
-  end
 end
-
-require Protocol
-
-Protocol.derive(
-  Inspect,
-  Macro.Env,
-  only: [
-    :module,
-    :file,
-    :line,
-    :function,
-    :context,
-    :aliases,
-    :requires,
-    :functions,
-    :macros,
-    :macro_aliases,
-    :context_modules,
-    :lexical_tracker
-  ]
-)

lib/elixir/lib/integer.ex

@@ -1,15 +1,6 @@
 defmodule Integer do
   @moduledoc """
   Functions for working with integers.
-
-  Some functions that work on integers are found in `Kernel`:
-
-    * `abs/1`
-    * `div/2`
-    * `max/2`
-    * `min/2`
-    * `rem/2`
-
   """
 
   import Bitwise
@@ -37,7 +28,9 @@ defmodule Integer do
       false
 
   """
-  defguard is_odd(integer) when is_integer(integer) and (integer &&& 1) == 1
+  defmacro is_odd(integer) do
+    quote do: (unquote(integer) &&& 1) == 1
+  end
 
   @doc """
   Determines if an `integer` is even.
@@ -62,55 +55,14 @@ defmodule Integer do
       true
 
   """
-  defguard is_even(integer) when is_integer(integer) and (integer &&& 1) == 0
-
-  @doc """
-  Computes `base` raised to power of `exponent`.
-
-  Both `base` and `exponent` must be integers.
-  The exponent must be zero or positive.
-
-  See `Float.pow/2` for exponentiation of negative
-  exponents as well as floats.
-
-  ## Examples
-
-      iex> Integer.pow(2, 0)
-      1
-      iex> Integer.pow(2, 1)
-      2
-      iex> Integer.pow(2, 10)
-      1024
-      iex> Integer.pow(2, 11)
-      2048
-      iex> Integer.pow(2, 64)
-      0x10000000000000000
-
-      iex> Integer.pow(3, 4)
-      81
-      iex> Integer.pow(4, 3)
-      64
-
-      iex> Integer.pow(-2, 3)
-      -8
-      iex> Integer.pow(-2, 4)
-      16
-
-      iex> Integer.pow(2, -2)
-      ** (ArithmeticError) bad argument in arithmetic expression
-
-  """
-  @doc since: "1.12.0"
-  @spec pow(integer, non_neg_integer) :: integer
-  def pow(base, exponent) when is_integer(base) and is_integer(exponent) do
-    if exponent < 0, do: :erlang.error(:badarith, [base, exponent])
-    base ** exponent
+  defmacro is_even(integer) do
+    quote do: (unquote(integer) &&& 1) == 0
   end
 
   @doc """
   Computes the modulo remainder of an integer division.
 
-  This function performs a [floored division](`floor_div/2`), which means that
+  `Integer.mod/2` uses floored division, which means that
   the result will always have the sign of the `divisor`.
 
   Raises an `ArithmeticError` exception if one of the arguments is not an
@@ -124,11 +76,9 @@ defmodule Integer do
       -2
 
   """
-  @doc since: "1.4.0"
   @spec mod(integer, neg_integer | pos_integer) :: integer
   def mod(dividend, divisor) do
     remainder = rem(dividend, divisor)
-
     if remainder * divisor < 0 do
       remainder + divisor
     else
@@ -142,8 +92,8 @@ defmodule Integer do
   Raises an `ArithmeticError` exception if one of the arguments is not an
   integer, or when the `divisor` is `0`.
 
-  This function performs a *floored* integer division, which means that
-  the result will always be rounded towards negative infinity.
+  `Integer.floor_div/2` performs *floored* integer division. This means that
+  the result is always rounded towards negative infinity.
 
   If you want to perform truncated integer division (rounding towards zero),
   use `Kernel.div/2` instead.
@@ -158,10 +108,9 @@ defmodule Integer do
       -50
 
   """
-  @doc since: "1.4.0"
   @spec floor_div(integer, neg_integer | pos_integer) :: integer
   def floor_div(dividend, divisor) do
-    if dividend * divisor < 0 and rem(dividend, divisor) != 0 do
+    if (dividend * divisor < 0) and rem(dividend, divisor) != 0 do
       div(dividend, divisor) - 1
     else
       div(dividend, divisor)
@@ -192,8 +141,14 @@ defmodule Integer do
     do_digits(integer, base, [])
   end
 
-  defp do_digits(integer, base, acc) when abs(integer) < base, do: [integer | acc]
-
+  defp do_digits(digit, base, []) when abs(digit) < base,
+    do: [digit]
+  defp do_digits(digit, base, []) when digit == -base,
+    do: [-1, 0]
+  defp do_digits(base, base, []),
+    do: [1, 0]
+  defp do_digits(0, _base, acc),
+    do: acc
   defp do_digits(integer, base, acc),
     do: do_digits(div(integer, base), base, [rem(integer, base) | acc])
 
@@ -201,7 +156,7 @@ defmodule Integer do
   Returns the integer represented by the ordered `digits`.
 
   An optional `base` value may be provided representing the radix for the `digits`.
-  Base has to be an integer greater than or equal to `2`.
+  This one can be an integer >= 2.
 
   ## Examples
 
@@ -215,16 +170,24 @@ defmodule Integer do
       0
 
   """
-  @spec undigits([integer], pos_integer) :: integer
+  @spec undigits([integer], integer) :: integer
   def undigits(digits, base \\ 10) when is_list(digits) and is_integer(base) and base >= 2 do
     do_undigits(digits, base, 0)
   end
 
-  defp do_undigits([], _base, acc), do: acc
+  defp do_undigits([], _base, 0),
+    do: 0
+  defp do_undigits([digit], base, 0) when is_integer(digit) and digit < base,
+    do: digit
+  defp do_undigits([1, 0], base, 0),
+    do: base
+  defp do_undigits([0 | tail], base, 0),
+    do: do_undigits(tail, base, 0)
 
+  defp do_undigits([], _base, acc),
+    do: acc
   defp do_undigits([digit | _], base, _) when is_integer(digit) and digit >= base,
-    do: raise(ArgumentError, "invalid digit #{digit} in base #{base}")
-
+    do: raise ArgumentError, "invalid digit #{digit} in base #{base}"
   defp do_undigits([digit | tail], base, acc) when is_integer(digit),
     do: do_undigits(tail, base, acc * base + digit)
 
@@ -239,7 +202,7 @@ defmodule Integer do
 
   Raises an error if `base` is less than 2 or more than 36.
 
-  If you want to convert a string-formatted integer directly to an integer,
+  If you want to convert a string-formatted integer directly to a integer,
   `String.to_integer/1` or `String.to_integer/2` can be used instead.
 
   ## Examples
@@ -269,55 +232,78 @@ defmodule Integer do
       ** (ArgumentError) invalid base 38
 
   """
-  @spec parse(binary, 2..36) :: {integer, remainder_of_binary :: binary} | :error
+  @spec parse(binary, 2..36) :: {integer, binary} | :error | no_return
   def parse(binary, base \\ 10)
 
-  def parse(_binary, base) when base not in 2..36 do
-    raise ArgumentError, "invalid base #{inspect(base)}"
+  def parse("", base) when base in 2..36,
+    do: :error
+
+  def parse(binary, base) when is_binary(binary) and base in 2..36 do
+    parse_in_base(binary, base)
   end
 
   def parse(binary, base) when is_binary(binary) do
-    case count_digits(binary, base) do
-      0 ->
-        :error
+    raise ArgumentError, "invalid base #{base}"
+  end
 
-      count ->
-        {digits, rem} = :erlang.split_binary(binary, count)
-        {:erlang.binary_to_integer(digits, base), rem}
+  defp parse_in_base("-" <> bin, base) do
+    case do_parse(bin, base) do
+      {number, remainder} -> {-number, remainder}
+      :error -> :error
     end
   end
 
-  defp count_digits(<<sign, rest::bits>>, base) when sign in '+-' do
-    case count_digits_nosign(rest, base, 1) do
-      1 -> 0
-      count -> count
+  defp parse_in_base("+" <> bin, base) do
+    do_parse(bin, base)
+  end
+
+  defp parse_in_base(binary, base) when is_binary(binary) do
+    do_parse(binary, base)
+  end
+
+  defp do_parse(<<char, rest::binary>>, base) do
+    if valid_digit_in_base?(char, base) do
+      do_parse(rest, base, parse_digit(char))
+    else
+      :error
     end
   end
 
-  defp count_digits(<<rest::bits>>, base) do
-    count_digits_nosign(rest, base, 0)
+  defp do_parse(_, _) do
+    :error
   end
 
-  digits = [{?0..?9, -?0}, {?A..?Z, 10 - ?A}, {?a..?z, 10 - ?a}]
-
-  for {chars, diff} <- digits,
-      char <- chars do
-    digit = char + diff
-
-    defp count_digits_nosign(<<unquote(char), rest::bits>>, base, count)
-         when base > unquote(digit) do
-      count_digits_nosign(rest, base, count + 1)
+  defp do_parse(<<char, rest::binary>> = bin, base, acc) do
+    if valid_digit_in_base?(char, base) do
+      do_parse(rest, base, base * acc + parse_digit(char))
+    else
+      {acc, bin}
     end
   end
 
-  defp count_digits_nosign(<<_::bits>>, _, count), do: count
+  defp do_parse(bitstring, _, acc) do
+    {acc, bitstring}
+  end
+
+  defp parse_digit(char) do
+    cond do
+      char in ?0..?9 -> char - ?0
+      char in ?A..?Z -> char - ?A + 10
+      true           -> char - ?a + 10
+    end
+  end
+
+  defp valid_digit_in_base?(char, base) do
+    if base <= 10 do
+      char in ?0..(?0 + base - 1)
+    else
+      char in ?0..?9 or char in ?A..(?A + base - 11) or char in ?a..(?a + base - 11)
+    end
+  end
 
   @doc """
   Returns a binary which corresponds to the text representation
-  of `integer` in the given `base`.
-
-  `base` can be an integer between 2 and 36. If no `base` is given,
-  it defaults to `10`.
+  of `integer`.
 
   Inlined by the compiler.
 
@@ -335,27 +321,39 @@ defmodule Integer do
       iex> Integer.to_string(0123)
       "123"
 
+  """
+  @spec to_string(integer) :: String.t
+  def to_string(integer) do
+    :erlang.integer_to_binary(integer)
+  end
+
+  @doc """
+  Returns a binary which corresponds to the text representation
+  of `integer` in the given `base`.
+
+  `base` can be an integer between 2 and 36.
+
+  Inlined by the compiler.
+
+  ## Examples
+
       iex> Integer.to_string(100, 16)
       "64"
 
       iex> Integer.to_string(-100, 16)
       "-64"
 
-      iex> Integer.to_string(882_681_651, 36)
+      iex> Integer.to_string(882681651, 36)
       "ELIXIR"
 
   """
-  @spec to_string(integer, 2..36) :: String.t()
-  def to_string(integer, base \\ 10) do
+  @spec to_string(integer, 2..36) :: String.t
+  def to_string(integer, base) do
     :erlang.integer_to_binary(integer, base)
   end
 
   @doc """
-  Returns a charlist which corresponds to the text representation
-  of `integer` in the given `base`.
-
-  `base` can be an integer between 2 and 36. If no `base` is given,
-  it defaults to `10`.
+  Returns a charlist which corresponds to the text representation of the given `integer`.
 
   Inlined by the compiler.
 
@@ -373,117 +371,38 @@ defmodule Integer do
       iex> Integer.to_charlist(0123)
       '123'
 
+  """
+  @spec to_charlist(integer) :: charlist
+  def to_charlist(integer) do
+    :erlang.integer_to_list(integer)
+  end
+
+  @doc """
+  Returns a charlist which corresponds to the text representation of `integer` in the given `base`.
+
+  `base` can be an integer between 2 and 36.
+
+  Inlined by the compiler.
+
+  ## Examples
+
       iex> Integer.to_charlist(100, 16)
       '64'
 
       iex> Integer.to_charlist(-100, 16)
       '-64'
 
-      iex> Integer.to_charlist(882_681_651, 36)
+      iex> Integer.to_charlist(882681651, 36)
       'ELIXIR'
 
   """
   @spec to_charlist(integer, 2..36) :: charlist
-  def to_charlist(integer, base \\ 10) do
+  def to_charlist(integer, base) do
     :erlang.integer_to_list(integer, base)
   end
 
-  @doc """
-  Returns the greatest common divisor of the two given integers.
-
-  The greatest common divisor (GCD) of `integer1` and `integer2` is the largest positive
-  integer that divides both `integer1` and `integer2` without leaving a remainder.
-
-  By convention, `gcd(0, 0)` returns `0`.
-
-  ## Examples
-
-      iex> Integer.gcd(2, 3)
-      1
-
-      iex> Integer.gcd(8, 12)
-      4
-
-      iex> Integer.gcd(8, -12)
-      4
-
-      iex> Integer.gcd(10, 0)
-      10
-
-      iex> Integer.gcd(7, 7)
-      7
-
-      iex> Integer.gcd(0, 0)
-      0
-
-  """
-  @doc since: "1.5.0"
-  @spec gcd(integer, integer) :: non_neg_integer
-  def gcd(integer1, integer2) when is_integer(integer1) and is_integer(integer2) do
-    gcd_positive(abs(integer1), abs(integer2))
-  end
-
-  defp gcd_positive(0, integer2), do: integer2
-  defp gcd_positive(integer1, 0), do: integer1
-  defp gcd_positive(integer1, integer2), do: gcd_positive(integer2, rem(integer1, integer2))
-
-  @doc """
-  Returns the extended greatest common divisor of the two given integers.
-
-  This function uses the extended Euclidean algorithm to return a three-element tuple with the `gcd`
-  and the coefficients `m` and `n` of Bézout's identity such that:
-
-      gcd(a, b) = m*a + n*b
-
-  By convention, `extended_gcd(0, 0)` returns `{0, 0, 0}`.
-
-  ## Examples
-
-      iex> Integer.extended_gcd(240, 46)
-      {2, -9, 47}
-      iex> Integer.extended_gcd(46, 240)
-      {2, 47, -9}
-      iex> Integer.extended_gcd(-46, 240)
-      {2, -47, -9}
-      iex> Integer.extended_gcd(-46, -240)
-      {2, -47, 9}
-
-      iex> Integer.extended_gcd(14, 21)
-      {7, -1, 1}
-
-      iex> Integer.extended_gcd(10, 0)
-      {10, 1, 0}
-      iex> Integer.extended_gcd(0, 10)
-      {10, 0, 1}
-      iex> Integer.extended_gcd(0, 0)
-      {0, 0, 0}
-
-  """
-  @doc since: "1.12.0"
-  @spec extended_gcd(integer, integer) :: {non_neg_integer, integer, integer}
-  def extended_gcd(0, 0), do: {0, 0, 0}
-  def extended_gcd(0, b), do: {b, 0, 1}
-  def extended_gcd(a, 0), do: {a, 1, 0}
-
-  def extended_gcd(integer1, integer2) when is_integer(integer1) and is_integer(integer2) do
-    extended_gcd(integer2, integer1, 0, 1, 1, 0)
-  end
-
-  defp extended_gcd(r1, r0, s1, s0, t1, t0) do
-    div = div(r0, r1)
-
-    case r0 - div * r1 do
-      0 when r1 > 0 -> {r1, s1, t1}
-      0 when r1 < 0 -> {-r1, -s1, -t1}
-      r2 -> extended_gcd(r2, r1, s0 - div * s1, s1, t0 - div * t1, t1)
-    end
-  end
-
+  # TODO: Deprecate by v1.5
   @doc false
-  @deprecated "Use Integer.to_charlist/1 instead"
+  @spec to_char_list(integer) :: charlist
   def to_char_list(integer), do: Integer.to_charlist(integer)
-
-  @doc false
-  @deprecated "Use Integer.to_charlist/2 instead"
-  def to_char_list(integer, base), do: Integer.to_charlist(integer, base)
 end

lib/elixir/lib/io.ex

@@ -1,5 +1,5 @@
 defmodule IO do
-  @moduledoc ~S"""
+  @moduledoc """
   Functions handling input/output (IO).
 
   Many functions in this module expect an IO device as an argument.
@@ -7,10 +7,13 @@ defmodule IO do
   For convenience, Elixir provides `:stdio` and `:stderr` as
   shortcuts to Erlang's `:standard_io` and `:standard_error`.
 
-  The majority of the functions expect chardata. In case another type is given,
-  functions will convert those types to string via the `String.Chars` protocol
-  (as shown in typespecs). For more information on chardata, see the
-  "IO data" section below.
+  The majority of the functions expect chardata, i.e. strings or
+  lists of characters and strings. In case another type is given,
+  functions will convert to string via the `String.Chars` protocol
+  (as shown in typespecs).
+
+  The functions starting with `bin` expect iodata as an argument,
+  i.e. binaries or lists of bytes and binaries.
 
   ## IO devices
 
@@ -24,112 +27,29 @@ defmodule IO do
     * `:stderr` - a shortcut for the named process `:standard_error`
       provided in Erlang
 
-  IO devices maintain their position, which means subsequent calls to any
-  reading or writing functions will start from the place where the device
-  was last accessed. The position of files can be changed using the
+  IO devices maintain their position, that means subsequent calls to any
+  reading or writing functions will start from the place when the device
+  was last accessed. Position of files can be changed using the
   `:file.position/2` function.
 
-  ## IO data
-
-  IO data is a data type that can be used as a more efficient alternative to binaries
-  in certain situations.
-
-  A term of type **IO data** is a binary or a list containing bytes (integers within the `0..255` range)
-  or nested IO data. The type is recursive. Let's see an example of one of
-  the possible IO data representing the binary `"hello"`:
-
-      [?h, "el", ["l", [?o]]]
-
-  The built-in `t:iodata/0` type is defined in terms of `t:iolist/0`. An IO list is
-  the same as IO data but it doesn't allow for a binary at the top level (but binaries
-  are still allowed in the list itself).
-
-  ### Use cases for IO data
-
-  IO data exists because often you need to do many append operations
-  on smaller chunks of binaries in order to create a bigger binary. However, in
-  Erlang and Elixir concatenating binaries will copy the concatenated binaries
-  into a new binary.
-
-      def email(username, domain) do
-        username <> "@" <> domain
-      end
-
-  In this function, creating the email address will copy the `username` and `domain`
-  binaries. Now imagine you want to use the resulting email inside another binary:
-
-      def welcome_message(name, username, domain) do
-        "Welcome #{name}, your email is: #{email(username, domain)}"
-      end
-
-      IO.puts(welcome_message("Meg", "meg", "example.com"))
-      #=> "Welcome Meg, your email is: meg@example.com"
-
-  Every time you concatenate binaries or use interpolation (`#{}`) you are making
-  copies of those binaries. However, in many cases you don't need the complete
-  binary while you create it, but only at the end to print it out or send it
-  somewhere. In such cases, you can construct the binary by creating IO data:
-
-      def email(username, domain) do
-        [username, ?@, domain]
-      end
-
-      def welcome_message(name, username, domain) do
-        ["Welcome ", name, ", your email is: ", email(username, domain)]
-      end
-
-      IO.puts(welcome_message("Meg", "meg", "example.com"))
-      #=> "Welcome Meg, your email is: meg@example.com"
-
-  Building IO data is cheaper than concatenating binaries. Concatenating multiple
-  pieces of IO data just means putting them together inside a list since IO data
-  can be arbitrarily nested, and that's a cheap and efficient operation. Most of
-  the IO-based APIs, such as `:gen_tcp` and `IO`, receive IO data and write it
-  to the socket directly without converting it to binary.
-
-  One drawback of IO data is that you can't do things like pattern match on the
-  first part of a piece of IO data like you can with a binary, because you usually
-  don't know the shape of the IO data. In those cases, you may need to convert it
-  to a binary by calling `iodata_to_binary/1`, which is reasonably efficient
-  since it's implemented natively in C. Other functionality, like computing the
-  length of IO data, can be computed directly on the iodata by calling `iodata_length/1`.
-
-  ### Chardata
-
-  Erlang and Elixir also have the idea of `t:chardata/0`. Chardata is very
-  similar to IO data: the only difference is that integers in IO data represent
-  bytes while integers in chardata represent Unicode code points. Bytes
-  (`t:byte/0`) are integers within the `0..255` range, while Unicode code points
-  (`t:char/0`) are integers within the `0..0x10FFFF` range. The `IO` module provides
-  the `chardata_to_string/1` function for chardata as the "counter-part" of the
-  `iodata_to_binary/1` function for IO data.
-
-  If you try to use `iodata_to_binary/1` on chardata, it will result in an
-  argument error. For example, let's try to put a code point that is not
-  representable with one byte, like `?π`, inside IO data:
-
-      IO.iodata_to_binary(["The symbol for pi is: ", ?π])
-      #=> ** (ArgumentError) argument error
-
-  If we use chardata instead, it will work as expected:
-
-      iex> IO.chardata_to_string(["The symbol for pi is: ", ?π])
-      "The symbol for pi is: π"
-
   """
 
   @type device :: atom | pid
   @type nodata :: {:error, term} | :eof
-  @type chardata :: String.t() | maybe_improper_list(char | chardata, String.t() | [])
+  @type chardata() :: :unicode.chardata()
 
-  defguardp is_device(term) when is_atom(term) or is_pid(term)
-  defguardp is_iodata(data) when is_list(data) or is_binary(data)
+  defmacrop is_iodata(data) do
+    quote do
+      is_list(unquote(data)) or is_binary(unquote(data))
+    end
+  end
 
   @doc """
   Reads from the IO `device`.
 
-  The `device` is iterated by the given number of characters, line by line if
-  `:line` is given, or until `:eof`.
+  The `device` is iterated by the given number of characters or line by line if
+  `:line` is given.
+  Alternatively, if `:all` is given, then whole `device` is returned.
 
   It returns:
 
@@ -141,24 +61,14 @@ defmodule IO do
       for instance, `{:error, :estale}` if reading from an
       NFS volume
 
+  If `:all` is given, `:eof` is never returned, but an
+  empty string in case the device has reached EOF.
   """
-  @spec read(device, :eof | :line | non_neg_integer) :: chardata | nodata
+  @spec read(device, :all | :line | non_neg_integer) :: chardata | nodata
   def read(device \\ :stdio, line_or_chars)
 
-  # TODO: Deprecate me on v1.17
   def read(device, :all) do
-    with :eof <- read(device, :eof) do
-      with [_ | _] = opts <- :io.getopts(device),
-           false <- Keyword.get(opts, :binary, true) do
-        ''
-      else
-        _ -> ""
-      end
-    end
-  end
-
-  def read(device, :eof) do
-    getn(device, '', :eof)
+    do_read_all(map_dev(device), "")
   end
 
   def read(device, :line) do
@@ -169,11 +79,20 @@ defmodule IO do
     :io.get_chars(map_dev(device), '', count)
   end
 
+  defp do_read_all(mapped_dev, acc) do
+    case :io.get_line(mapped_dev, "") do
+      line when is_binary(line) -> do_read_all(mapped_dev, acc <> line)
+      :eof -> acc
+      other -> other
+    end
+  end
+
   @doc """
   Reads from the IO `device`. The operation is Unicode unsafe.
 
-  The `device` is iterated by the given number of bytes, line by line if
-  `:line` is given, or until `:eof`.
+  The `device` is iterated by the given number of bytes or line by line if
+  `:line` is given.
+  Alternatively, if `:all` is given, then whole `device` is returned.
 
   It returns:
 
@@ -185,19 +104,17 @@ defmodule IO do
       for instance, `{:error, :estale}` if reading from an
       NFS volume
 
+  If `:all` is given, `:eof` is never returned, but an
+  empty string in case the device has reached EOF.
+
   Note: do not use this function on IO devices in Unicode mode
   as it will return the wrong result.
   """
-  @spec binread(device, :eof | :line | non_neg_integer) :: iodata | nodata
+  @spec binread(device, :all | :line | non_neg_integer) :: iodata | nodata
   def binread(device \\ :stdio, line_or_chars)
 
-  # TODO: Deprecate me on v1.17
   def binread(device, :all) do
-    with :eof <- binread(device, :eof), do: ""
-  end
-
-  def binread(device, :eof) do
-    binread_eof(map_dev(device), "")
+    do_binread_all(map_dev(device), "")
   end
 
   def binread(device, :line) do
@@ -215,74 +132,56 @@ defmodule IO do
   end
 
   @read_all_size 4096
-  defp binread_eof(mapped_dev, acc) do
+  defp do_binread_all(mapped_dev, acc) do
     case :file.read(mapped_dev, @read_all_size) do
-      {:ok, data} -> binread_eof(mapped_dev, acc <> data)
-      :eof -> if acc == "", do: :eof, else: acc
+      {:ok, data} -> do_binread_all(mapped_dev, acc <> data)
+      :eof -> acc
       other -> other
     end
   end
 
   @doc """
-  Writes `chardata` to the given `device`.
+  Writes `item` to the given `device`.
 
-  By default, the `device` is the standard output.
+  By default the `device` is the standard output.
+  It returns `:ok` if it succeeds.
 
   ## Examples
 
-      IO.write("sample")
+      IO.write "sample"
       #=> sample
 
-      IO.write(:stderr, "error")
+      IO.write :stderr, "error"
       #=> error
 
   """
-  @spec write(device, chardata | String.Chars.t()) :: :ok
-  def write(device \\ :stdio, chardata) do
-    :io.put_chars(map_dev(device), to_chardata(chardata))
+  @spec write(device, chardata | String.Chars.t) :: :ok
+  def write(device \\ :stdio, item) do
+    :io.put_chars map_dev(device), to_chardata(item)
   end
 
   @doc """
-  Writes `iodata` to the given `device`.
+  Writes `item` as a binary to the given `device`.
+  No Unicode conversion happens.
+  The operation is Unicode unsafe.
 
-  This operation is meant to be used with "raw" devices
-  that are started without an encoding. The given `iodata`
-  is written as is to the device, without conversion. For
-  more information on IO data, see the "IO data" section in
-  the module documentation.
+  Check `write/2` for more information.
 
-  Use `write/2` for devices with encoding.
-
-  Important: do **not** use this function on IO devices in
-  Unicode mode as it will write the wrong data. In particular,
-  the standard IO device is set to Unicode by default, so writing
-  to stdio with this function will likely result in the wrong data
-  being sent down the wire.
+  Note: do not use this function on IO devices in Unicode mode
+  as it will return the wrong result.
   """
   @spec binwrite(device, iodata) :: :ok | {:error, term}
-  def binwrite(device \\ :stdio, iodata) when is_iodata(iodata) do
-    :file.write(map_dev(device), iodata)
+  def binwrite(device \\ :stdio, item) when is_iodata(item) do
+    :file.write map_dev(device), item
   end
 
   @doc """
   Writes `item` to the given `device`, similar to `write/2`,
   but adds a newline at the end.
-
-  By default, the `device` is the standard output. It returns `:ok`
-  if it succeeds.
-
-  ## Examples
-
-      IO.puts("Hello World!")
-      #=> Hello World!
-
-      IO.puts(:stderr, "error")
-      #=> error
-
   """
-  @spec puts(device, chardata | String.Chars.t()) :: :ok
-  def puts(device \\ :stdio, item) when is_device(device) do
-    :io.put_chars(map_dev(device), [to_chardata(item), ?\n])
+  @spec puts(device, chardata | String.Chars.t) :: :ok
+  def puts(device \\ :stdio, item) do
+    :io.put_chars map_dev(device), [to_chardata(item), ?\n]
   end
 
   @doc """
@@ -297,41 +196,18 @@ defmodule IO do
   ## Examples
 
       stacktrace = [{MyApp, :main, 1, [file: 'my_app.ex', line: 4]}]
-      IO.warn("variable bar is unused", stacktrace)
+      IO.warn "variable bar is unused", stacktrace
       #=> warning: variable bar is unused
       #=>   my_app.ex:4: MyApp.main/1
 
   """
-  @spec warn(chardata | String.Chars.t(), Exception.stacktrace()) :: :ok
+  @spec warn(chardata | String.Chars.t, Exception.stacktrace) :: :ok
   def warn(message, []) do
-    message = [to_chardata(message), ?\n]
-    :elixir_errors.log_and_print_warning(0, nil, message, message)
+    :elixir_errors.warn([to_chardata(message), ?\n])
   end
-
-  def warn(message, [{_, _, _, opts} | _] = stacktrace) do
-    message = to_chardata(message)
-    formatted_trace = Enum.map_join(stacktrace, "\n  ", &Exception.format_stacktrace_entry(&1))
-    line = opts[:line]
-    file = opts[:file]
-
-    :elixir_errors.log_and_print_warning(
-      line || 0,
-      file && List.to_string(file),
-      message,
-      [message, ?\n, "  ", formatted_trace, ?\n]
-    )
-  end
-
-  @doc false
-  def warn_once(key, message, stacktrace_drop_levels) do
-    {:current_stacktrace, stacktrace} = Process.info(self(), :current_stacktrace)
-    stacktrace = Enum.drop(stacktrace, stacktrace_drop_levels)
-
-    if :elixir_config.warn(key, stacktrace) do
-      warn(message, stacktrace)
-    else
-      :ok
-    end
+  def warn(message, stacktrace) when is_list(stacktrace) do
+    formatted = Enum.map_join(stacktrace, "\n  ", &Exception.format_stacktrace_entry(&1))
+    :elixir_errors.warn([to_chardata(message), ?\n, "  ", formatted, ?\n])
   end
 
   @doc """
@@ -339,19 +215,14 @@ defmodule IO do
 
   It returns `:ok` if it succeeds.
 
-  Do not call this function at the tail of another function. Due to tail
-  call optimization, a stacktrace entry would not be added and the
-  stacktrace would be incorrectly trimmed. Therefore make sure at least
-  one expression (or an atom such as `:ok`) follows the `IO.warn/1` call.
-
   ## Examples
 
-      IO.warn("variable bar is unused")
+      IO.warn "variable bar is unused"
       #=> warning: variable bar is unused
       #=>   (iex) evaluator.ex:108: IEx.Evaluator.eval/4
 
   """
-  @spec warn(chardata | String.Chars.t()) :: :ok
+  @spec warn(chardata | String.Chars.t) :: :ok
   def warn(message) do
     {:current_stacktrace, stacktrace} = Process.info(self(), :current_stacktrace)
     warn(message, Enum.drop(stacktrace, 2))
@@ -377,7 +248,7 @@ defmodule IO do
 
   ## Examples
 
-      IO.inspect(<<0, 1, 2>>, width: 40)
+      IO.inspect <<0, 1, 2>>, width: 40
 
   Prints:
 
@@ -385,7 +256,7 @@ defmodule IO do
 
   We can use the `:label` option to decorate the output:
 
-      IO.inspect(1..100, label: "a wonderful range")
+      IO.inspect 1..100, label: "a wonderful range"
 
   Prints:
 
@@ -397,7 +268,7 @@ defmodule IO do
       |> IO.inspect(label: "before")
       |> Enum.map(&(&1 * 2))
       |> IO.inspect(label: "after")
-      |> Enum.sum()
+      |> Enum.sum
 
   Prints:
 
@@ -405,9 +276,9 @@ defmodule IO do
       after: [2, 4, 6]
 
   """
-  @spec inspect(item, keyword) :: item when item: var
+  @spec inspect(item, Keyword.t) :: item when item: var
   def inspect(item, opts \\ []) do
-    inspect(:stdio, item, opts)
+    inspect :stdio, item, opts
   end
 
   @doc """
@@ -415,13 +286,12 @@ defmodule IO do
 
   See `inspect/2` for a full list of options.
   """
-  @spec inspect(device, item, keyword) :: item when item: var
-  def inspect(device, item, opts) when is_device(device) and is_list(opts) do
-    label = if label = opts[:label], do: [to_chardata(label), ": "], else: []
-    opts = Inspect.Opts.new(opts)
-    doc = Inspect.Algebra.group(Inspect.Algebra.to_doc(item, opts))
-    chardata = Inspect.Algebra.format(doc, opts.width)
-    puts(device, [label, chardata])
+  @spec inspect(device, item, Keyword.t) :: item when item: var
+  def inspect(device, item, opts) when is_list(opts) do
+    label    = if (label = opts[:label]), do: [to_chardata(label), ": "], else: []
+    opts     = struct(Inspect.Opts, opts)
+    chardata = Inspect.Algebra.format(Inspect.Algebra.to_doc(item, opts), opts.width)
+    puts device, [label, chardata]
     item
   end
 
@@ -429,21 +299,15 @@ defmodule IO do
   Gets a number of bytes from IO device `:stdio`.
 
   If `:stdio` is a Unicode device, `count` implies
-  the number of Unicode code points to be retrieved.
+  the number of Unicode codepoints to be retrieved.
   Otherwise, `count` is the number of raw bytes to be retrieved.
 
   See `IO.getn/3` for a description of return values.
-  """
-  @spec getn(
-          device | chardata | String.Chars.t(),
-          pos_integer | :eof | chardata | String.Chars.t()
-        ) ::
-          chardata | nodata
-  def getn(prompt, count \\ 1)
 
-  def getn(prompt, :eof) do
-    getn(:stdio, prompt, :eof)
-  end
+  """
+  @spec getn(chardata | String.Chars.t, pos_integer) :: chardata | nodata
+  @spec getn(device, chardata | String.Chars.t) :: chardata | nodata
+  def getn(prompt, count \\ 1)
 
   def getn(prompt, count) when is_integer(count) and count > 0 do
     getn(:stdio, prompt, count)
@@ -457,7 +321,7 @@ 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 code points to be retrieved.
+  the number of Unicode codepoints to be retrieved.
   Otherwise, `count` is the number of raw bytes to be retrieved.
 
   It returns:
@@ -471,27 +335,11 @@ defmodule IO do
       NFS volume
 
   """
-  @spec getn(device, chardata | String.Chars.t(), pos_integer | :eof) :: chardata | nodata
-  def getn(device, prompt, :eof) do
-    getn_eof(map_dev(device), to_chardata(prompt), [])
-  end
-
+  @spec getn(device, chardata | String.Chars.t, pos_integer) :: chardata | nodata
   def getn(device, prompt, count) when is_integer(count) and count > 0 do
     :io.get_chars(map_dev(device), to_chardata(prompt), count)
   end
 
-  defp getn_eof(device, prompt, acc) do
-    case :io.get_line(device, prompt) do
-      line when is_binary(line) or is_list(line) -> getn_eof(device, '', [line | acc])
-      :eof -> wrap_eof(:lists.reverse(acc))
-      other -> other
-    end
-  end
-
-  defp wrap_eof([h | _] = acc) when is_binary(h), do: IO.iodata_to_binary(acc)
-  defp wrap_eof([h | _] = acc) when is_list(h), do: :lists.flatten(acc)
-  defp wrap_eof([]), do: :eof
-
   @doc ~S"""
   Reads a line from the IO `device`.
 
@@ -510,25 +358,14 @@ defmodule IO do
 
   To display "What is your name?" as a prompt and await user input:
 
-      IO.gets("What is your name?\n")
+      IO.gets "What is your name?\n"
 
   """
-  @spec gets(device, chardata | String.Chars.t()) :: chardata | nodata
+  @spec gets(device, chardata | String.Chars.t) :: chardata | nodata
   def gets(device \\ :stdio, prompt) do
     :io.get_line(map_dev(device), to_chardata(prompt))
   end
 
-  @doc """
-  Returns a line-based `IO.Stream` on `:stdio`.
-
-  This is equivalent to:
-
-      IO.stream(:stdio, :line)
-
-  """
-  @doc since: "1.12.0"
-  def stream, do: stream(:stdio, :line)
-
   @doc """
   Converts the IO `device` into an `IO.Stream`.
 
@@ -545,35 +382,21 @@ defmodule IO do
   Note that an IO stream has side effects and every time
   you go over the stream you may get different results.
 
-  `stream/1` has been introduced in Elixir v1.12.0,
-  while `stream/2` has been available since v1.0.0.
-
   ## 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)
 
   """
-  @spec stream(device, :line | pos_integer) :: Enumerable.t()
-  def stream(device \\ :stdio, line_or_codepoints)
+  @spec stream(device, :line | pos_integer) :: Enumerable.t
+  def stream(device, line_or_codepoints)
       when line_or_codepoints == :line
       when is_integer(line_or_codepoints) and line_or_codepoints > 0 do
     IO.Stream.__build__(map_dev(device), false, line_or_codepoints)
   end
 
-  @doc """
-  Returns a raw, line-based `IO.Stream` on `:stdio`. The operation is Unicode unsafe.
-
-  This is equivalent to:
-
-      IO.binstream(:stdio, :line)
-
-  """
-  @doc since: "1.12.0"
-  def binstream, do: binstream(:stdio, :line)
-
   @doc """
   Converts the IO `device` into an `IO.Stream`. The operation is Unicode unsafe.
 
@@ -582,7 +405,8 @@ defmodule IO do
   and write.
 
   The `device` is iterated by the given number of bytes or line by line if
-  `:line` is given. This reads from the IO device as a raw binary.
+  `:line` is given.
+  This reads from the IO device as a raw binary.
 
   Note that an IO stream has side effects and every time
   you go over the stream you may get different results.
@@ -590,21 +414,17 @@ defmodule IO do
   Finally, do not use this function on IO devices in Unicode
   mode as it will return the wrong result.
 
-  `binstream/1` has been introduced in Elixir v1.12.0,
-  while `binstream/2` has been available since v1.0.0.
   """
-  @spec binstream(device, :line | pos_integer) :: Enumerable.t()
-  def binstream(device \\ :stdio, line_or_bytes)
+  @spec binstream(device, :line | pos_integer) :: Enumerable.t
+  def binstream(device, line_or_bytes)
       when line_or_bytes == :line
       when is_integer(line_or_bytes) and line_or_bytes > 0 do
     IO.Stream.__build__(map_dev(device), true, line_or_bytes)
   end
 
   @doc """
-  Converts chardata into a string.
-
-  For more information about chardata, see the ["Chardata"](#module-chardata)
-  section in the module documentation.
+  Converts chardata (a list of integers representing codepoints,
+  lists and strings) into a string.
 
   In case the conversion fails, it raises an `UnicodeConversionError`.
   If a string is given, it returns the string itself.
@@ -621,9 +441,7 @@ defmodule IO do
       "string"
 
   """
-  @spec chardata_to_string(chardata) :: String.t()
-  def chardata_to_string(chardata)
-
+  @spec chardata_to_string(chardata) :: String.t | no_return
   def chardata_to_string(string) when is_binary(string) do
     string
   end
@@ -633,16 +451,14 @@ defmodule IO do
   end
 
   @doc """
-  Converts IO data into a binary
-
+  Converts iodata (a list of integers representing bytes, lists
+  and binaries) into a binary.
   The operation is Unicode unsafe.
 
-  Note that this function treats integers in the given IO data as
-  raw bytes and does not perform any kind of encoding conversion.
-  If you want to convert from a charlist to a UTF-8-encoded string,
-  use `chardata_to_string/1` instead. For more information about
-  IO data and chardata, see the ["IO data"](#module-io-data) section in the
-  module documentation.
+  Notice that this function treats lists of integers as raw bytes
+  and does not perform any kind of encoding conversion. If you want
+  to convert from a charlist to a string (UTF-8 encoded), please
+  use `chardata_to_string/1` instead.
 
   If this function receives a binary, the same binary is returned.
 
@@ -662,15 +478,12 @@ defmodule IO do
 
   """
   @spec iodata_to_binary(iodata) :: binary
-  def iodata_to_binary(iodata) do
-    :erlang.iolist_to_binary(iodata)
+  def iodata_to_binary(item) do
+    :erlang.iolist_to_binary(item)
   end
 
   @doc """
-  Returns the size of an IO data.
-
-  For more information about IO data, see the ["IO data"](#module-io-data)
-  section in the module documentation.
+  Returns the size of an iodata.
 
   Inlined by the compiler.
 
@@ -681,8 +494,8 @@ defmodule IO do
 
   """
   @spec iodata_length(iodata) :: non_neg_integer
-  def iodata_length(iodata) do
-    :erlang.iolist_size(iodata)
+  def iodata_length(item) do
+    :erlang.iolist_size(item)
   end
 
   @doc false
@@ -690,10 +503,8 @@ defmodule IO do
     case read(device, line_or_codepoints) do
       :eof ->
         {:halt, device}
-
       {:error, reason} ->
         raise IO.StreamError, reason: reason
-
       data ->
         {[data], device}
     end
@@ -704,10 +515,8 @@ defmodule IO do
     case binread(device, line_or_chars) do
       :eof ->
         {:halt, device}
-
       {:error, reason} ->
         raise IO.StreamError, reason: reason
-
       data ->
         {[data], device}
     end
@@ -716,7 +525,7 @@ defmodule IO do
   @compile {:inline, map_dev: 1, to_chardata: 1}
 
   # Map the Elixir names for standard IO and error to Erlang names
-  defp map_dev(:stdio), do: :standard_io
+  defp map_dev(:stdio),  do: :standard_io
   defp map_dev(:stderr), do: :standard_error
   defp map_dev(other) when is_atom(other) or is_pid(other) or is_tuple(other), do: other
 

lib/elixir/lib/io/ansi.ex

@@ -21,39 +21,13 @@ defmodule IO.ANSI do
   [ANSI escape sequences](https://en.wikipedia.org/wiki/ANSI_escape_code)
   are characters embedded in text used to control formatting, color, and
   other output options on video text terminals.
-
-  ANSI escapes are typically enabled on all Unix terminals. They are also
-  available on Windows consoles from Windows 10, although it must be
-  explicitly enabled for the current user in the registry by running the
-  following command:
-
-      reg add HKCU\\Console /v VirtualTerminalLevel /t REG_DWORD /d 1
-
-  After running the command above, you must restart your current console.
-
-  ## Examples
-
-  Because the ANSI escape sequences are embedded in text, the normal usage of
-  these functions is to concatenate their output with text.
-
-      formatted_text = IO.ANSI.blue_background() <> "Example" <> IO.ANSI.reset()
-      IO.puts(formatted_text)
-
-  A higher level and more convenient API is also available via `IO.ANSI.format/1`,
-  where you use atoms to represent each ANSI escape sequence and by default
-  checks if ANSI is enabled:
-
-      IO.puts(IO.ANSI.format([:blue_background, "Example"]))
-
-  In case ANSI is disabled, the ANSI escape sequences are simply discarded.
   """
 
   import IO.ANSI.Sequence
 
-  @type ansicode :: atom
-  @type ansilist ::
-          maybe_improper_list(char | ansicode | binary | ansilist, binary | ansicode | [])
-  @type ansidata :: ansilist | ansicode | binary
+  @typep ansicode :: atom
+  @typep ansilist :: maybe_improper_list(char | ansicode | binary | ansilist, binary | ansicode | [])
+  @type  ansidata :: ansilist | ansicode | binary
 
   @doc """
   Checks if ANSI coloring is supported and enabled on this machine.
@@ -69,7 +43,7 @@ defmodule IO.ANSI do
   end
 
   @doc "Sets foreground color."
-  @spec color(0..255) :: String.t()
+  @spec color(0..255) :: String.t
   def color(code) when code in 0..255, do: "\e[38;5;#{code}m"
 
   @doc ~S"""
@@ -77,13 +51,13 @@ defmodule IO.ANSI do
 
   Valid values for each color are in the range 0 to 5.
   """
-  @spec color(0..5, 0..5, 0..5) :: String.t()
+  @spec color(0..5, 0..5, 0..5) :: String.t
   def color(r, g, b) when r in 0..5 and g in 0..5 and b in 0..5 do
-    color(16 + 36 * r + 6 * g + b)
+    color(16 + (36 * r) + (6 * g) + b)
   end
 
   @doc "Sets background color."
-  @spec color_background(0..255) :: String.t()
+  @spec color_background(0..255) :: String.t
   def color_background(code) when code in 0..255, do: "\e[48;5;#{code}m"
 
   @doc ~S"""
@@ -91,145 +65,118 @@ defmodule IO.ANSI do
 
   Valid values for each color are in the range 0 to 5.
   """
-  @spec color_background(0..5, 0..5, 0..5) :: String.t()
+  @spec color_background(0..5, 0..5, 0..5) :: String.t
   def color_background(r, g, b) when r in 0..5 and g in 0..5 and b in 0..5 do
-    color_background(16 + 36 * r + 6 * g + b)
+    color_background(16 + (36 * r) + (6 * g) + b)
   end
 
   @doc "Resets all attributes."
-  defsequence(:reset, 0)
+  defsequence :reset, 0
 
   @doc "Bright (increased intensity) or bold."
-  defsequence(:bright, 1)
+  defsequence :bright, 1
 
   @doc "Faint (decreased intensity). Not widely supported."
-  defsequence(:faint, 2)
+  defsequence :faint, 2
 
   @doc "Italic: on. Not widely supported. Sometimes treated as inverse."
-  defsequence(:italic, 3)
+  defsequence :italic, 3
 
   @doc "Underline: single."
-  defsequence(:underline, 4)
+  defsequence :underline, 4
 
   @doc "Blink: slow. Less than 150 per minute."
-  defsequence(:blink_slow, 5)
+  defsequence :blink_slow, 5
 
   @doc "Blink: rapid. MS-DOS ANSI.SYS; 150 per minute or more; not widely supported."
-  defsequence(:blink_rapid, 6)
+  defsequence :blink_rapid, 6
 
   @doc "Image: negative. Swap foreground and background."
-  defsequence(:inverse, 7)
+  defsequence :inverse, 7
 
   @doc "Image: negative. Swap foreground and background."
-  defsequence(:reverse, 7)
+  defsequence :reverse, 7
 
   @doc "Conceal. Not widely supported."
-  defsequence(:conceal, 8)
+  defsequence :conceal, 8
 
   @doc "Crossed-out. Characters legible, but marked for deletion. Not widely supported."
-  defsequence(:crossed_out, 9)
+  defsequence :crossed_out, 9
 
   @doc "Sets primary (default) font."
-  defsequence(:primary_font, 10)
+  defsequence :primary_font, 10
 
   for font_n <- [1, 2, 3, 4, 5, 6, 7, 8, 9] do
     @doc "Sets alternative font #{font_n}."
-    defsequence(:"font_#{font_n}", font_n + 10)
+    defsequence :"font_#{font_n}", font_n + 10
   end
 
   @doc "Normal color or intensity."
-  defsequence(:normal, 22)
+  defsequence :normal, 22
 
   @doc "Not italic."
-  defsequence(:not_italic, 23)
+  defsequence :not_italic, 23
 
   @doc "Underline: none."
-  defsequence(:no_underline, 24)
+  defsequence :no_underline, 24
 
   @doc "Blink: off."
-  defsequence(:blink_off, 25)
+  defsequence :blink_off, 25
 
   @doc "Image: positive. Normal foreground and background."
-  defsequence(:inverse_off, 27)
+  defsequence :inverse_off, 27
 
   @doc "Image: positive. Normal foreground and background."
-  defsequence(:reverse_off, 27)
+  defsequence :reverse_off, 27
 
   colors = [:black, :red, :green, :yellow, :blue, :magenta, :cyan, :white]
 
   for {color, code} <- Enum.with_index(colors) do
     @doc "Sets foreground color to #{color}."
-    defsequence(color, code + 30)
+    defsequence color, code + 30
 
     @doc "Sets foreground color to light #{color}."
-    defsequence(:"light_#{color}", code + 90)
+    defsequence :"light_#{color}", code + 90
 
     @doc "Sets background color to #{color}."
-    defsequence(:"#{color}_background", code + 40)
+    defsequence :"#{color}_background", code + 40
 
     @doc "Sets background color to light #{color}."
-    defsequence(:"light_#{color}_background", code + 100)
+    defsequence :"light_#{color}_background", code + 100
   end
 
   @doc "Default text color."
-  defsequence(:default_color, 39)
+  defsequence :default_color, 39
 
   @doc "Default background color."
-  defsequence(:default_background, 49)
+  defsequence :default_background, 49
 
   @doc "Framed."
-  defsequence(:framed, 51)
+  defsequence :framed, 51
 
   @doc "Encircled."
-  defsequence(:encircled, 52)
+  defsequence :encircled, 52
 
   @doc "Overlined."
-  defsequence(:overlined, 53)
+  defsequence :overlined, 53
 
   @doc "Not framed or encircled."
-  defsequence(:not_framed_encircled, 54)
+  defsequence :not_framed_encircled, 54
 
   @doc "Not overlined."
-  defsequence(:not_overlined, 55)
+  defsequence :not_overlined, 55
 
   @doc "Sends cursor home."
-  defsequence(:home, "", "H")
-
-  @doc """
-  Sends cursor to the absolute position specified by `line` and `column`.
-
-  Line `0` and column `0` would mean the top left corner.
-  """
-  @spec cursor(non_neg_integer, non_neg_integer) :: String.t()
-  def cursor(line, column)
-      when is_integer(line) and line >= 0 and is_integer(column) and column >= 0 do
-    "\e[#{line};#{column}H"
-  end
-
-  @doc "Sends cursor `lines` up."
-  @spec cursor_up(pos_integer) :: String.t()
-  def cursor_up(lines \\ 1) when is_integer(lines) and lines >= 1, do: "\e[#{lines}A"
-
-  @doc "Sends cursor `lines` down."
-  @spec cursor_down(pos_integer) :: String.t()
-  def cursor_down(lines \\ 1) when is_integer(lines) and lines >= 1, do: "\e[#{lines}B"
-
-  @doc "Sends cursor `columns` to the right."
-  @spec cursor_right(pos_integer) :: String.t()
-  def cursor_right(columns \\ 1) when is_integer(columns) and columns >= 1, do: "\e[#{columns}C"
-
-  @doc "Sends cursor `columns` to the left."
-  @spec cursor_left(pos_integer) :: String.t()
-  def cursor_left(columns \\ 1) when is_integer(columns) and columns >= 1, do: "\e[#{columns}D"
+  defsequence :home, "", "H"
 
   @doc "Clears screen."
-  defsequence(:clear, "2", "J")
+  defsequence :clear, "2", "J"
 
   @doc "Clears line."
-  defsequence(:clear_line, "2", "K")
+  defsequence :clear_line, "2", "K"
 
   defp format_sequence(other) do
-    raise ArgumentError, "invalid ANSI sequence specification: #{inspect(other)}"
+    raise ArgumentError, "invalid ANSI sequence specification: #{inspect other}"
   end
 
   @doc ~S"""
@@ -242,7 +189,7 @@ defmodule IO.ANSI do
   performed. If you don't want this behaviour, use `format_fragment/2`.
 
   An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When `false`, no ANSI codes will be emitted.
+  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
   By default checks if ANSI is enabled using the `enabled?/0` function.
 
   ## Examples
@@ -262,7 +209,7 @@ defmodule IO.ANSI do
   The named sequences are represented by atoms.
 
   An optional boolean parameter can be passed to enable or disable
-  emitting actual ANSI codes. When `false`, no ANSI codes will be emitted.
+  emitting actual ANSI codes. When `false`, no ANSI codes will emitted.
   By default checks if ANSI is enabled using the `enabled?/0` function.
 
   ## Examples
@@ -296,7 +243,7 @@ defmodule IO.ANSI do
   end
 
   defp do_format([], [], acc, true, true) do
-    [acc | IO.ANSI.reset()]
+    [acc | IO.ANSI.reset]
   end
 
   defp do_format([], [], acc, _emit?, _append_reset) do

lib/elixir/lib/io/ansi/docs.ex

@@ -1,24 +1,20 @@
 defmodule IO.ANSI.Docs do
   @moduledoc false
 
-  @bullet_text_unicode "• "
-  @bullet_text_ascii "* "
   @bullets [?*, ?-, ?+]
   @spaces [" ", "\n", "\t"]
 
   @doc """
   The default options used by this module.
 
-  The supported keys are:
+  The supported values are:
 
     * `:enabled`           - toggles coloring on and off (true)
     * `:doc_bold`          - bold text (bright)
     * `:doc_code`          - code blocks (cyan)
     * `:doc_headings`      - h1, h2, h3, h4, h5, h6 headings (yellow)
-    * `:doc_metadata`      - documentation metadata keys (yellow)
-    * `:doc_quote`         - leading quote character `> ` (light black)
     * `:doc_inline_code`   - inline code (cyan)
-    * `:doc_table_heading` - the style for table headings
+    * `:doc_table_heading` - style for table headings
     * `:doc_title`         - top level heading (reverse, yellow)
     * `:doc_underline`     - underlined text (underline)
     * `:width`             - the width to format the text (80)
@@ -26,21 +22,16 @@ defmodule IO.ANSI.Docs do
   Values for the color settings are strings with
   comma-separated ANSI values.
   """
-  @spec default_options() :: keyword
   def default_options do
-    [
-      enabled: true,
-      doc_bold: [:bright],
-      doc_code: [:cyan],
-      doc_headings: [:yellow],
-      doc_metadata: [:yellow],
-      doc_quote: [:light_black],
-      doc_inline_code: [:cyan],
-      doc_table_heading: [:reverse],
-      doc_title: [:reverse, :yellow],
-      doc_underline: [:underline],
-      width: 80
-    ]
+    [enabled:           true,
+     doc_bold:          [:bright],
+     doc_code:          [:cyan],
+     doc_headings:      [:yellow],
+     doc_inline_code:   [:cyan],
+     doc_table_heading: [:reverse],
+     doc_title:         [:reverse, :yellow],
+     doc_underline:     [:underline],
+     width:             80]
   end
 
   @doc """
@@ -48,265 +39,24 @@ defmodule IO.ANSI.Docs do
 
   See `default_options/0` for docs on the supported options.
   """
-  @spec print_headings([String.t()], keyword) :: :ok
-  def print_headings(headings, options \\ []) do
+  def print_heading(heading, options \\ []) do
+    IO.puts IO.ANSI.reset
     options = Keyword.merge(default_options(), options)
-    newline_after_block(options)
-    width = options[:width]
-
-    for heading <- headings do
-      padding = div(width + String.length(heading), 2)
-      heading = String.pad_leading(heading, padding)
-      heading = if options[:enabled], do: String.pad_trailing(heading, width), else: heading
-      write(:doc_title, heading, options)
-    end
-
-    newline_after_block(options)
+    width   = options[:width]
+    padding = div(width + String.length(heading), 2)
+    heading = heading |> String.pad_leading(padding) |> String.pad_trailing(width)
+    write(:doc_title, heading, options)
+    newline_after_block()
   end
 
   @doc """
-  Prints documentation metadata (only `delegate_to`, `deprecated`, `guard`, and `since` for now).
+  Prints the documentation body.
 
-  See `default_options/0` for docs on the supported options.
+  In addition to the printing string, takes a set of options
+  defined in `default_options/1`.
   """
-  @spec print_metadata(map, keyword) :: :ok
-  def print_metadata(metadata, options \\ []) when is_map(metadata) do
+  def print(doc, options \\ []) do
     options = Keyword.merge(default_options(), options)
-    print_each_metadata(metadata, options) && IO.write("\n")
-  end
-
-  @metadata_filter [:deprecated, :guard, :since]
-
-  defp print_each_metadata(metadata, options) do
-    Enum.reduce(metadata, false, fn
-      {key, value}, _printed when is_binary(value) and key in @metadata_filter ->
-        label = metadata_label(key, options)
-        indent = String.duplicate(" ", length_without_escape(label, 0) + 1)
-        write_with_wrap([label | String.split(value, @spaces)], options[:width], indent, true, "")
-
-      {key, value}, _printed when is_boolean(value) and key in @metadata_filter ->
-        IO.puts([metadata_label(key, options), ?\s, to_string(value)])
-
-      {:delegate_to, {m, f, a}}, _printed ->
-        label = metadata_label(:delegate_to, options)
-        IO.puts([label, ?\s, Exception.format_mfa(m, f, a)])
-
-      _metadata, printed ->
-        printed
-    end)
-  end
-
-  defp metadata_label(key, options) do
-    "#{color(:doc_metadata, options)}#{key}:#{maybe_reset(options)}"
-  end
-
-  @doc """
-  Prints the documentation body `doc` according to `format`.
-
-  It takes a set of `options` defined in `default_options/0`.
-  """
-  @spec print(term(), String.t(), keyword) :: :ok
-  def print(doc, format, options \\ [])
-
-  def print(doc, "text/markdown", options) when is_binary(doc) and is_list(options) do
-    print_markdown(doc, options)
-  end
-
-  def print(doc, "application/erlang+html", options) when is_list(options) do
-    print_erlang_html(doc, options)
-  end
-
-  def print(_doc, format, options) when is_binary(format) and is_list(options) do
-    IO.puts("\nUnknown documentation format #{inspect(format)}\n")
-  end
-
-  ## Erlang+html
-
-  def print_erlang_html(doc, options) do
-    options = Keyword.merge(default_options(), options)
-    IO.write(traverse_erlang_html(doc, "", options))
-  end
-
-  defp traverse_erlang_html(text, _indent, _options) when is_binary(text) do
-    text
-  end
-
-  defp traverse_erlang_html(nodes, indent, options) when is_list(nodes) do
-    for node <- nodes do
-      traverse_erlang_html(node, indent, options)
-    end
-  end
-
-  defp traverse_erlang_html({:div, [class: class] ++ _, entries}, indent, options) do
-    prefix = indent <> quote_prefix(options)
-
-    content =
-      entries
-      |> traverse_erlang_html(indent, options)
-      |> IO.iodata_to_binary()
-      |> String.trim_trailing()
-
-    [
-      prefix,
-      class |> to_string() |> String.upcase(),
-      "\n#{prefix}\n#{prefix}" | String.replace(content, "\n", "\n#{prefix}")
-    ]
-    |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:p, _, entries}, indent, options) do
-    [indent | handle_erlang_html_text(entries, indent, options)]
-  end
-
-  defp traverse_erlang_html({:h1, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(1, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:h2, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(2, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:h3, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(3, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:h4, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(4, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:h5, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(5, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:h6, _, entries}, indent, options) do
-    entries |> traverse_erlang_html(indent, options) |> heading(6, options) |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:br, _, []}, _indent, _options) do
-    []
-  end
-
-  defp traverse_erlang_html({:i, _, entries}, indent, options) do
-    inline_text("_", traverse_erlang_html(entries, indent, options), options)
-  end
-
-  defp traverse_erlang_html({:em, _, entries}, indent, options) do
-    inline_text("*", traverse_erlang_html(entries, indent, options), options)
-  end
-
-  defp traverse_erlang_html({tag, _, entries}, indent, options) when tag in [:strong, :b] do
-    inline_text("**", traverse_erlang_html(entries, indent, options), options)
-  end
-
-  defp traverse_erlang_html({:code, _, entries}, indent, options) do
-    inline_text("`", traverse_erlang_html(entries, indent, options), options)
-  end
-
-  defp traverse_erlang_html({:pre, _, [{:code, _, entries}]}, indent, options) do
-    string =
-      entries
-      |> traverse_erlang_html(indent, options)
-      |> IO.iodata_to_binary()
-
-    ["#{indent}    ", String.replace(string, "\n", "\n#{indent}    ")] |> newline_cons()
-  end
-
-  defp traverse_erlang_html({:a, attributes, entries}, indent, options) do
-    if href = attributes[:href] do
-      [traverse_erlang_html(entries, indent, options), ?\s, ?(, href, ?)]
-    else
-      traverse_erlang_html(entries, indent, options)
-    end
-  end
-
-  defp traverse_erlang_html({:dl, _, entries}, indent, options) do
-    traverse_erlang_html(entries, indent, options)
-  end
-
-  defp traverse_erlang_html({:dt, _, entries}, indent, options) do
-    [
-      "#{indent}  ",
-      bullet_text(options) | handle_erlang_html_text(entries, indent <> "    ", options)
-    ]
-  end
-
-  defp traverse_erlang_html({:dd, _, entries}, indent, options) do
-    ["#{indent}    " | handle_erlang_html_text(entries, indent <> "    ", options)]
-  end
-
-  defp traverse_erlang_html({:ul, attributes, entries}, indent, options) do
-    if attributes[:class] == "types" do
-      types =
-        for {:li, _, lines} <- entries,
-            line <- lines,
-            do: ["#{indent}    ", traverse_erlang_html(line, indent <> "    ", options), ?\n]
-
-      if types != [] do
-        ["#{indent}Typespecs:\n\n", types, ?\n]
-      else
-        []
-      end
-    else
-      for {:li, _, lines} <- entries do
-        [
-          "#{indent}  ",
-          bullet_text(options) | handle_erlang_html_text(lines, indent <> "    ", options)
-        ]
-      end
-    end
-  end
-
-  defp traverse_erlang_html({:ol, _, entries}, indent, options) do
-    for {{:li, _, lines}, i} <- Enum.with_index(entries, 1) do
-      [
-        "#{indent}  ",
-        Integer.to_string(i),
-        ". " | handle_erlang_html_text(lines, indent <> "     ", options)
-      ]
-    end
-  end
-
-  defp traverse_erlang_html({tag, _, entries}, indent, options) do
-    [
-      indent <> "<#{tag}>\n",
-      traverse_erlang_html(entries, indent <> "    ", options)
-      |> IO.iodata_to_binary()
-      |> String.trim_trailing(),
-      "\n" <> indent <> "</#{tag}>"
-    ]
-    |> newline_cons()
-  end
-
-  defp newline_cons(text) do
-    [text | "\n\n"]
-  end
-
-  defp handle_erlang_html_text(entries, indent, options) do
-    if Enum.all?(entries, &inline_html?/1) do
-      entries
-      |> traverse_erlang_html(indent, options)
-      |> IO.iodata_to_binary()
-      |> String.split(@spaces)
-      |> wrap_text(options[:width], indent, true, "", [])
-      |> tl()
-      |> newline_cons()
-    else
-      entries
-      |> traverse_erlang_html(indent, options)
-      |> IO.iodata_to_binary()
-      |> String.trim_leading()
-    end
-  end
-
-  defp inline_html?(binary) when is_binary(binary), do: true
-  defp inline_html?({tag, _, _}) when tag in [:a, :code, :em, :i, :strong, :b, :br], do: true
-  defp inline_html?(_), do: false
-
-  ## Markdown
-
-  def print_markdown(doc, options) do
-    options = Keyword.merge(default_options(), options)
-
     doc
     |> String.split(["\r\n", "\n"], trim: false)
     |> Enum.map(&String.trim_trailing/1)
@@ -320,32 +70,22 @@ defmodule IO.ANSI.Docs do
   defp process(["# " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
-
   defp process(["## " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
-
   defp process(["### " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
-
   defp process(["#### " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
-
   defp process(["##### " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
-
   defp process(["###### " <> _ = heading | rest], text, indent, options) do
     write_heading(heading, rest, text, indent, options)
   end
 
-  defp process([">" <> line | rest], text, indent, options) do
-    write_text(text, indent, options)
-    process_quote(rest, [line], indent, options)
-  end
-
   defp process(["" | rest], text, indent, options) do
     write_text(text, indent, options)
     process(rest, [], indent, options)
@@ -364,87 +104,42 @@ defmodule IO.ANSI.Docs do
     process_fenced_code_block(rest, text, indent, options, _delimiter = "~~~")
   end
 
-  defp process(all = [line | rest], text, indent, options) do
+  defp process(all=[line | rest], text, indent, options) do
     {stripped, count} = strip_spaces(line, 0, :infinity)
-
     cond do
       link_label?(stripped, count) ->
         write_text([line], indent, options, true)
         process(rest, text, indent, options)
-
       table_line?(stripped) and rest != [] and table_line?(hd(rest)) ->
         write_text(text, indent, options)
         process_table(all, indent, options)
-
       true ->
         process_rest(stripped, rest, count, text, indent, options)
     end
   end
 
-  ### Headings
+  ## Headings
 
   defp write_heading(heading, rest, text, indent, options) do
     write_text(text, indent, options)
     write(:doc_headings, heading, options)
-    newline_after_block(options)
+    newline_after_block()
     process(rest, [], "", options)
   end
 
-  ### Quotes
-
-  defp process_quote([], lines, indent, options) do
-    write_quote(lines, indent, options, false)
-  end
-
-  defp process_quote([">", ">" <> line | rest], lines, indent, options) do
-    write_quote(lines, indent, options, true)
-    write_empty_quote_line(options)
-    process_quote(rest, [line], indent, options)
-  end
-
-  defp process_quote([">" <> line | rest], lines, indent, options) do
-    process_quote(rest, [line | lines], indent, options)
-  end
-
-  defp process_quote(rest, lines, indent, options) do
-    write_quote(lines, indent, options, false)
-    process(rest, [], indent, options)
-  end
-
-  defp write_quote(lines, indent, options, no_wrap) do
-    lines
-    |> Enum.map(&String.trim/1)
-    |> Enum.reverse()
-    |> write_lines(
-      indent,
-      options,
-      no_wrap,
-      quote_prefix(options)
-    )
-  end
-
-  defp write_empty_quote_line(options) do
-    options
-    |> quote_prefix()
-    |> IO.puts()
-  end
-
-  ### Lists
+  ## Lists
 
   defp process_rest(stripped, rest, count, text, indent, options) do
     case stripped do
       <<bullet, ?\s, item::binary>> when bullet in @bullets ->
         write_text(text, indent, options)
-        process_list(bullet_text(options), item, rest, count, indent, options)
-
+        process_list("• ", item, rest, count, indent, options)
       <<d1, ?., ?\s, item::binary>> when d1 in ?0..?9 ->
         write_text(text, indent, options)
         process_list(<<d1, ?., ?\s>>, item, rest, count, indent, options)
-
       <<d1, d2, ?., ?\s, item::binary>> when d1 in ?0..?9 and d2 in ?0..?9 ->
         write_text(text, indent, options)
         process_list(<<d1, d2, ?., ?\s>>, item, rest, count, indent, options)
-
       _ ->
         process(rest, [stripped | text], indent, options)
     end
@@ -455,18 +150,15 @@ defmodule IO.ANSI.Docs do
     entry = if indent == "", do: "  " <> entry, else: entry
     new_indent = indent <> String.duplicate(" ", String.length(entry))
 
-    {contents, rest, done} =
-      process_list_next(rest, count, byte_size(new_indent) - byte_size(indent), [])
-
+    {contents, rest, done} = process_list_next(rest, count, byte_size(new_indent), [])
     process(contents, [indent <> entry <> line, :no_wrap], new_indent, options)
 
-    if done, do: newline_after_block(options)
+    if done, do: newline_after_block()
     process(rest, [], indent, options)
   end
 
   defp process_list_next([line | rest], count, max, acc) do
     {stripped, next_count} = strip_spaces(line, 0, max)
-
     case process_list_next_kind(stripped, rest, count, next_count) do
       :next -> process_list_next(rest, count, max, [stripped | acc])
       :done -> {Enum.reverse(acc), [line | rest], true}
@@ -482,26 +174,20 @@ defmodule IO.ANSI.Docs do
     case {stripped, rest} do
       {<<bullet, ?\s, _::binary>>, _} when bullet in @bullets and next_count <= count ->
         :list
-
       {<<d1, ?., ?\s, _::binary>>, _} when d1 in ?0..?9 and next_count <= count ->
         :list
-
-      {<<d1, d2, ?., ?\s, _::binary>>, _}
-      when d1 in ?0..?9 and d2 in ?0..?9 and next_count <= count ->
+      {<<d1, d2, ?., ?\s, _::binary>>, _} when d1 in ?0..?9 and d2 in ?0..?9 and next_count <= count ->
         :list
-
       {"", [" " <> _ | _]} ->
         :next
-
       {"", _} ->
         :done
-
       _ ->
         :next
     end
   end
 
-  ### Text
+  ## Text
 
   defp write_text(text, indent, options) do
     case Enum.reverse(text) do
@@ -515,26 +201,17 @@ defmodule IO.ANSI.Docs do
   end
 
   defp write_text(lines, indent, options, no_wrap) do
-    write_lines(lines, indent, options, no_wrap, "")
-  end
-
-  defp write_lines(lines, indent, options, no_wrap, prefix) do
     lines
     |> Enum.join(" ")
-    |> format_text(options)
-    |> String.split(@spaces)
-    |> write_with_wrap(options[:width] - byte_size(indent), indent, no_wrap, prefix)
-
-    unless no_wrap, do: newline_after_block(options)
-  end
-
-  defp format_text(text, options) do
-    text
-    |> handle_links()
+    |> handle_links
     |> handle_inline(options)
+    |> String.split(@spaces)
+    |> write_with_wrap(options[:width] - byte_size(indent), indent, no_wrap)
+
+    unless no_wrap, do: newline_after_block()
   end
 
-  ### Code blocks
+  ## Code blocks
 
   defp process_code([], code, indent, options) do
     write_code(code, indent, options)
@@ -573,52 +250,49 @@ defmodule IO.ANSI.Docs do
 
   defp write_code(code, indent, options) do
     write(:doc_code, "#{indent}    #{Enum.join(Enum.reverse(code), "\n#{indent}    ")}", options)
-    newline_after_block(options)
+    newline_after_block()
   end
 
-  ### Tables
+  ## Tables
 
   defp process_table(lines, indent, options) do
     {table, rest} = Enum.split_while(lines, &table_line?/1)
     table_lines(table, options)
-    newline_after_block(options)
+    newline_after_block()
     process(rest, [], indent, options)
   end
 
   defp table_lines(lines, options) do
     lines = Enum.map(lines, &split_into_columns(&1, options))
-    count = Enum.map(lines, &length/1) |> Enum.max()
+    count = Enum.map(lines, &length/1) |> Enum.max
     lines = Enum.map(lines, &pad_to_number_of_columns(&1, count))
 
     widths =
       for line <- lines do
-        if table_header?(line) do
-          for _ <- line, do: 0
-        else
-          for {_col, length} <- line, do: length
-        end
+        for {_col, length} <- line, do: length
       end
 
-    col_widths = Enum.reduce(widths, List.duplicate(0, count), &max_column_widths/2)
+    col_widths = Enum.reduce(widths,
+                             List.duplicate(0, count),
+                             &max_column_widths/2)
+
     render_table(lines, col_widths, options)
   end
 
   defp split_into_columns(line, options) do
     line
-    |> String.trim(" ")
     |> String.trim("|")
-    |> String.split(~r{(?<!\\)\|})
+    |> String.trim()
+    |> String.split(" | ")
     |> Enum.map(&render_column(&1, options))
   end
 
   defp render_column(col, options) do
     col =
       col
-      |> String.trim()
       |> String.replace("\\\|", "|")
       |> handle_links
       |> handle_inline(options)
-
     {col, length_without_escape(col, 0)}
   end
 
@@ -631,10 +305,7 @@ defmodule IO.ANSI.Docs do
   # If second line is heading separator, use the heading style on the first
   defp render_table([first, second | rest], widths, options) do
     combined = Enum.zip(first, widths)
-
     if table_header?(second) do
-      alignments = Enum.map(second, &column_alignment/1)
-      options = Keyword.put_new(options, :alignments, alignments)
       draw_table_row(combined, options, :heading)
       render_table(rest, widths, options)
     else
@@ -649,65 +320,36 @@ defmodule IO.ANSI.Docs do
     render_table(rest, widths, options)
   end
 
-  defp render_table([], _, _), do: nil
+  defp render_table([], _, _),
+    do: nil
 
-  defp column_alignment({line, _}) do
-    cond do
-      String.starts_with?(line, ":") and String.ends_with?(line, ":") -> :center
-      String.ends_with?(line, ":") -> :right
-      true -> :left
-    end
+  defp table_header?(row) do
+    Enum.all?(row, fn {col, _} -> table_header_column?(col) end)
   end
 
-  defp table_header?(line) do
-    Enum.all?(line, fn {col, _} -> table_header_column?(col) end)
-  end
+  defp table_header_column?(":" <> row), do: table_header_contents?(row)
+  defp table_header_column?(row), do: table_header_contents?(row)
 
-  defp table_header_column?(":" <> rest), do: table_header_contents?(rest)
-  defp table_header_column?(col), do: table_header_contents?(col)
-
-  defp table_header_contents?("-" <> rest), do: table_header_contents?(rest)
+  defp table_header_contents?("-" <> row), do: table_header_contents?(row)
   defp table_header_contents?(":"), do: true
   defp table_header_contents?(""), do: true
   defp table_header_contents?(_), do: false
 
   defp draw_table_row(cols_and_widths, options, heading \\ false) do
-    default_alignments = List.duplicate(:left, length(cols_and_widths))
-    alignments = Keyword.get(options, :alignments, default_alignments)
-
     columns =
-      cols_and_widths
-      |> Enum.zip(alignments)
-      |> Enum.map_join(" | ", &generate_table_cell/1)
+      Enum.map_join(cols_and_widths, " | ", fn {{col, length}, width} ->
+        col <> String.duplicate(" ", width - length)
+      end)
 
     if heading do
       write(:doc_table_heading, columns, options)
     else
-      IO.puts(columns)
+      IO.puts columns
     end
   end
 
-  defp generate_table_cell({{{col, length}, width}, :center}) do
-    ansi_diff = byte_size(col) - length
-    width = width + ansi_diff
-
-    col
-    |> String.pad_leading(div(width, 2) - div(length, 2) + length)
-    |> String.pad_trailing(width + 1 - rem(width, 2))
-  end
-
-  defp generate_table_cell({{{col, length}, width}, :right}) do
-    ansi_diff = byte_size(col) - length
-    String.pad_leading(col, width + ansi_diff)
-  end
-
-  defp generate_table_cell({{{col, length}, width}, :left}) do
-    ansi_diff = byte_size(col) - length
-    String.pad_trailing(col, width + ansi_diff)
-  end
-
   defp table_line?(line) do
-    line =~ ~r/[:\ -]\|[:\ -]/
+    line =~ " | "
   end
 
   ## Helpers
@@ -720,34 +362,23 @@ defmodule IO.ANSI.Docs do
   defp link_label?(""), do: false
   defp link_label?(<<_>> <> rest), do: link_label?(rest)
 
-  defp strip_spaces(" " <> line, acc, max) when acc < max, do: strip_spaces(line, acc + 1, max)
-  defp strip_spaces(rest, acc, _max), do: {rest, acc}
+  defp strip_spaces(" " <> line, acc, max) when acc < max,
+    do: strip_spaces(line, acc + 1, max)
+  defp strip_spaces(rest, acc, _max),
+    do: {rest, acc}
 
   defp write(style, string, options) do
-    IO.puts([color(style, options), string, maybe_reset(options)])
+    IO.puts [color(style, options), string, IO.ANSI.reset]
   end
 
-  defp write_with_wrap([], _available, _indent, _first, _prefix) do
+  defp write_with_wrap([], _available, _indent, _first) do
     :ok
   end
 
-  defp write_with_wrap(words, available, indent, first, prefix) do
-    words
-    |> wrap_text(available, indent, first, prefix, [])
-    |> tl()
-    |> IO.puts()
-  end
-
-  defp wrap_text([], _available, _indent, _first, _prefix, wrapped_lines) do
-    Enum.reverse(wrapped_lines)
-  end
-
-  defp wrap_text(words, available, indent, first, prefix, wrapped_lines) do
-    prefix_length = length_without_escape(prefix, 0)
-    {words, rest} = take_words(words, available - prefix_length, [])
-    line = [if(first, do: "", else: indent), prefix, Enum.join(words, " ")]
-
-    wrap_text(rest, available, indent, false, prefix, [line, ?\n | wrapped_lines])
+  defp write_with_wrap(words, available, indent, first) do
+    {words, rest} = take_words(words, available, [])
+    IO.puts (if first, do: "", else: indent) <> Enum.join(words, " ")
+    write_with_wrap(rest, available, indent, false)
   end
 
   defp take_words([word | words], available, acc) do
@@ -794,22 +425,24 @@ defmodule IO.ANSI.Docs do
   end
 
   defp escape_underlines_in_link(text) do
-    # Regular expression adapted from https://tools.ietf.org/html/rfc3986#appendix-B
-    Regex.replace(~r{[a-z][a-z0-9\+\-\.]*://\S*}i, text, &String.replace(&1, "_", "\\_"))
+    ~r{https?\S*}
+    |> Regex.recompile!
+    |> Regex.replace(text, &String.replace(&1, "_", "\\_"))
   end
 
   defp remove_square_brackets_in_link(text) do
-    Regex.replace(~r{\[([^\]]*?)\]\((.*?)\)}, text, "\\1 (\\2)")
+    ~r{\[(.*?)\]\((.*?)\)}
+    |> Regex.recompile!
+    |> Regex.replace(text, "\\1 (\\2)")
   end
 
-  # We have four entries: **, __, *, _ and `.
+  # We have four entries: **, *, _ and `.
   #
-  # The first four behave the same while the last one is simpler
-  # when it comes to delimiters as it ignores spaces and escape
-  # characters. But, since the first two has two characters,
-  # we need to handle 3 cases:
+  # The first three behave the same while the last one is simpler
+  # when it comes to delimiters. But, since the first has two
+  # characters, we need to handle 3 cases:
   #
-  # 1. __ and **
+  # 1. **
   # 2. _ and *
   # 3. `
   #
@@ -818,13 +451,12 @@ defmodule IO.ANSI.Docs do
 
   # Characters that can mark the beginning or the end of a word.
   # Only support the most common ones at this moment.
-  @delimiters [?\s, ?', ?", ?!, ?@, ?#, ?$, ?%, ?^, ?&] ++
-                [?-, ?+, ?(, ?), ?[, ?], ?{, ?}, ?<, ?>, ?.]
+  @delimiters [?\s, ?', ?", ?!, ?@, ?#, ?$, ?%, ?^, ?&, ?-, ?+, ?(, ?), ?[, ?], ?{, ?}, ?<, ?>, ?.]
 
-  ### Inline start
+  # Inline start
 
-  defp handle_inline(<<mark, mark, rest::binary>>, options) when mark in @single do
-    handle_inline(rest, [mark | mark], [<<mark, mark>>], [], options)
+  defp handle_inline(<<?*, ?*, rest::binary>>, options) do
+    handle_inline(rest, ?d, ["**"], [], options)
   end
 
   defp handle_inline(<<mark, rest::binary>>, options) when mark in @single do
@@ -835,34 +467,32 @@ defmodule IO.ANSI.Docs do
     handle_inline(rest, nil, [], [], options)
   end
 
-  ### Inline delimiters
+  # Inline delimiters
 
-  defp handle_inline(<<delimiter, mark, mark, rest::binary>>, nil, buffer, acc, options)
-       when rest != "" and delimiter in @delimiters and mark in @single do
-    acc = [delimiter, Enum.reverse(buffer) | acc]
-    handle_inline(rest, [mark | mark], [<<mark, mark>>], acc, options)
+  defp handle_inline(<<delimiter, ?*, ?*, rest::binary>>, nil, buffer, acc, options)
+      when rest != "" and delimiter in @delimiters do
+    handle_inline(rest, ?d, ["**"], [delimiter, Enum.reverse(buffer) | acc], options)
   end
 
   defp handle_inline(<<delimiter, mark, rest::binary>>, nil, buffer, acc, options)
-       when rest != "" and delimiter in @delimiters and mark in @single do
+      when rest != "" and delimiter in @delimiters and mark in @single do
     handle_inline(rest, mark, [<<mark>>], [delimiter, Enum.reverse(buffer) | acc], options)
   end
 
   defp handle_inline(<<?`, rest::binary>>, nil, buffer, acc, options)
-       when rest != "" do
+      when rest != "" do
     handle_inline(rest, ?`, ["`"], [Enum.reverse(buffer) | acc], options)
   end
 
-  ### Clauses for handling escape
+  # Clauses for handling escape
 
-  defp handle_inline(<<?\\, ?\\, mark, mark, rest::binary>>, nil, buffer, acc, options)
-       when rest != "" and mark in @single do
-    acc = [?\\, Enum.reverse(buffer) | acc]
-    handle_inline(rest, [mark | mark], [<<mark, mark>>], acc, options)
+  defp handle_inline(<<?\\, ?\\, ?*, ?*, rest::binary>>, nil, buffer, acc, options)
+      when rest != "" do
+    handle_inline(rest, ?d, ["**"], [?\\, Enum.reverse(buffer) | acc], options)
   end
 
   defp handle_inline(<<?\\, ?\\, mark, rest::binary>>, nil, buffer, acc, options)
-       when rest != "" and mark in @single do
+      when rest != "" and mark in @single do
     handle_inline(rest, mark, [<<mark>>], [?\\, Enum.reverse(buffer) | acc], options)
   end
 
@@ -871,31 +501,30 @@ defmodule IO.ANSI.Docs do
   end
 
   # An escape is not valid inside `
-  defp handle_inline(<<?\\, mark, rest::binary>>, limit, buffer, acc, options) when limit != ?` do
+  defp handle_inline(<<?\\, mark, rest::binary>>, limit, buffer, acc, options)
+      when not(mark == limit and mark == ?`) do
     handle_inline(rest, limit, [mark | buffer], acc, options)
   end
 
-  ### Inline end
+  # Inline end
 
-  defp handle_inline(<<mark, mark, delimiter, rest::binary>>, [mark | mark], buffer, acc, options)
-       when delimiter in @delimiters and mark in @single do
-    inline_buffer = inline_buffer(buffer, options)
-    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer | acc], options)
+  defp handle_inline(<<?*, ?*, delimiter, rest::binary>>, ?d, buffer, acc, options)
+      when delimiter in @delimiters do
+    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer(buffer, options) | acc], options)
   end
 
   defp handle_inline(<<mark, delimiter, rest::binary>>, mark, buffer, acc, options)
-       when delimiter in @delimiters and mark in @single do
-    inline_buffer = inline_buffer(buffer, options)
-    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer | acc], options)
+      when delimiter in @delimiters and mark in @single do
+    handle_inline(<<delimiter, rest::binary>>, nil, [], [inline_buffer(buffer, options) | acc], options)
   end
 
-  defp handle_inline(<<mark, mark, rest::binary>>, [mark | mark], buffer, acc, options)
-       when rest == "" and mark in @single do
+  defp handle_inline(<<?*, ?*, rest::binary>>, ?d, buffer, acc, options)
+      when rest == "" do
     handle_inline(<<>>, nil, [], [inline_buffer(buffer, options) | acc], options)
   end
 
   defp handle_inline(<<mark, rest::binary>>, mark, buffer, acc, options)
-       when rest == "" and mark in @single do
+      when rest == "" and mark in @single do
     handle_inline(<<>>, nil, [], [inline_buffer(buffer, options) | acc], options)
   end
 
@@ -903,60 +532,34 @@ defmodule IO.ANSI.Docs do
     handle_inline(rest, nil, [], [inline_buffer(buffer, options) | acc], options)
   end
 
-  ### Catch all
+  # Catch all
 
   defp handle_inline(<<char, rest::binary>>, mark, buffer, acc, options) do
     handle_inline(rest, mark, [char | buffer], acc, options)
   end
 
   defp handle_inline(<<>>, _mark, buffer, acc, _options) do
-    IO.iodata_to_binary(Enum.reverse([Enum.reverse(buffer) | acc]))
+    IO.iodata_to_binary Enum.reverse([Enum.reverse(buffer) | acc])
   end
 
   defp inline_buffer(buffer, options) do
-    [mark | t] = Enum.reverse(buffer)
-    inline_text(mark, t, options)
-  end
-
-  ## Helpers
-
-  defp quote_prefix(options), do: "#{color(:doc_quote, options)}> #{maybe_reset(options)}"
-
-  defp heading(text, n, options) do
-    [color(:doc_headings, options), String.duplicate("#", n), " ", text, maybe_reset(options)]
-  end
-
-  defp inline_text(mark, text, options) do
-    if options[:enabled] do
-      [[color_for(mark, options) | text] | IO.ANSI.reset()]
-    else
-      [[mark | text] | mark]
-    end
+    [h | t] = Enum.reverse([IO.ANSI.reset | buffer])
+    [color_for(h, options) | t]
   end
 
   defp color_for(mark, colors) do
     case mark do
-      "__" -> color(:doc_bold, colors)
+      "`"  -> color(:doc_inline_code, colors)
+      "_"  -> color(:doc_underline, colors)
+      "*"  -> color(:doc_bold, colors)
       "**" -> color(:doc_bold, colors)
-      "_" -> color(:doc_underline, colors)
-      "*" -> color(:doc_underline, colors)
-      "`" -> color(:doc_inline_code, colors)
     end
   end
 
-  defp bullet_text(options) do
-    if options[:enabled], do: @bullet_text_unicode, else: @bullet_text_ascii
-  end
-
   defp color(style, colors) do
-    IO.ANSI.format_fragment(colors[style], colors[:enabled])
+    color = colors[style]
+    IO.ANSI.format_fragment(color, colors[:enabled])
   end
 
-  defp newline_after_block(options) do
-    IO.puts(maybe_reset(options))
-  end
-
-  defp maybe_reset(options) do
-    if options[:enabled], do: IO.ANSI.reset(), else: ""
-  end
+  defp newline_after_block, do: IO.puts(IO.ANSI.reset)
 end

lib/elixir/lib/io/stream.ex

@@ -1,9 +1,8 @@
 defmodule IO.StreamError do
   defexception [:reason, :message]
 
-  @impl true
   def exception(opts) do
-    reason = opts[:reason]
+    reason    = opts[:reason]
     formatted = IO.iodata_to_binary(:file.format_error(reason))
     %IO.StreamError{message: "error during streaming: #{formatted}", reason: reason}
   end
@@ -17,7 +16,7 @@ defmodule IO.Stream do
 
     * `device`        - the IO device
     * `raw`           - a boolean indicating if bin functions should be used
-    * `line_or_bytes` - if reading should read lines or a given number of bytes
+    * `line_or_bytes` - if reading should read lines or a given amount of bytes
 
   It is worth noting that an IO stream has side effects and every time you go
   over the stream you may get different results.
@@ -42,12 +41,10 @@ defmodule IO.Stream do
       fn
         :ok, {:cont, x} ->
           case raw do
-            true -> IO.binwrite(device, x)
+            true  -> IO.binwrite(device, x)
             false -> IO.write(device, x)
           end
-
-        :ok, _ ->
-          stream
+        :ok, _ -> stream
       end
     end
   end
@@ -56,11 +53,10 @@ defmodule IO.Stream do
     def reduce(%{device: device, raw: raw, line_or_bytes: line_or_bytes}, acc, fun) do
       next_fun =
         case raw do
-          true -> &IO.each_binstream(&1, line_or_bytes)
+          true  -> &IO.each_binstream(&1, line_or_bytes)
           false -> &IO.each_stream(&1, line_or_bytes)
         end
-
-      Stream.resource(fn -> device end, next_fun, & &1).(acc, fun)
+      Stream.resource(fn -> device end, next_fun, &(&1)).(acc, fun)
     end
 
     def count(_stream) do
@@ -70,9 +66,5 @@ defmodule IO.Stream do
     def member?(_stream, _term) do
       {:error, __MODULE__}
     end
-
-    def slice(_stream) do
-      {:error, __MODULE__}
-    end
   end
 end

lib/elixir/lib/kernel/cli.ex

@@ -1,22 +1,9 @@
 defmodule Kernel.CLI do
   @moduledoc false
 
-  @compile {:no_warn_undefined, [Logger, IEx]}
-
-  @blank_config %{
-    commands: [],
-    output: ".",
-    compile: [],
-    no_halt: false,
-    compiler_options: [],
-    errors: [],
-    pa: [],
-    pz: [],
-    verbose_compile: false,
-    profile: nil
-  }
-
-  @standalone_opts ["-h", "--help", "--short-version"]
+  @blank_config %{commands: [], output: ".", compile: [],
+                  halt: true, compiler_options: [], errors: [],
+                  pa: [], pz: [], verbose_compile: false}
 
   @doc """
   This is the API invoked by Elixir boot process.
@@ -26,18 +13,15 @@ defmodule Kernel.CLI do
 
     {config, argv} = parse_argv(argv)
     System.argv(argv)
-    System.no_halt(config.no_halt)
 
-    fun = fn _ ->
+    run fn _ ->
       errors = process_commands(config)
 
       if errors != [] do
         Enum.each(errors, &IO.puts(:stderr, &1))
         System.halt(1)
       end
-    end
-
-    run(fun)
+    end, config.halt
   end
 
   @doc """
@@ -48,10 +32,9 @@ defmodule Kernel.CLI do
   This function is used by Elixir's CLI and also
   by escripts generated by Elixir.
   """
-  def run(fun) do
+  def run(fun, halt \\ true) do
     {ok_or_shutdown, status} = exec_fun(fun, {:ok, 0})
-
-    if ok_or_shutdown == :shutdown or not System.no_halt() do
+    if ok_or_shutdown == :shutdown or halt do
       {_, status} = at_exit({ok_or_shutdown, status})
 
       # Ensure Logger messages are flushed before halting
@@ -64,51 +47,18 @@ defmodule Kernel.CLI do
     end
   end
 
-  @doc """
-  Parses the CLI arguments. Made public for testing.
-  """
+  @doc false
   def parse_argv(argv) do
     parse_argv(argv, @blank_config)
   end
 
-  @doc """
-  Process CLI commands. Made public for testing.
-  """
+  @doc false
   def process_commands(config) do
     results = Enum.map(Enum.reverse(config.commands), &process_command(&1, config))
-    errors = for {:error, msg} <- results, do: msg
+    errors  = for {:error, msg} <- results, do: msg
     Enum.reverse(config.errors, errors)
   end
 
-  @doc """
-  Shared helper for error formatting on CLI tools.
-  """
-  def format_error(kind, reason, stacktrace) do
-    {blamed, stacktrace} = Exception.blame(kind, reason, stacktrace)
-
-    iodata =
-      case blamed do
-        %FunctionClauseError{} ->
-          formatted = Exception.format_banner(kind, reason, stacktrace)
-          padded_blame = pad(FunctionClauseError.blame(blamed, &inspect/1, &blame_match/1))
-          [formatted, padded_blame]
-
-        _ ->
-          Exception.format_banner(kind, blamed, stacktrace)
-      end
-
-    [iodata, ?\n, Exception.format_stacktrace(prune_stacktrace(stacktrace))]
-  end
-
-  @doc """
-  Function invoked across nodes for `--rpc-eval`.
-  """
-  def rpc_eval(expr) do
-    wrapper(fn -> Code.eval_string(expr) end)
-  catch
-    kind, reason -> {kind, reason, __STACKTRACE__}
-  end
-
   ## Helpers
 
   defp at_exit(res) do
@@ -126,23 +76,22 @@ defmodule Kernel.CLI do
           fun.(elem(res, 1))
         catch
           :exit, {:shutdown, int} when is_integer(int) ->
-            send(parent, {self(), {:shutdown, int}})
+            send parent, {self(), {:shutdown, int}}
             exit({:shutdown, int})
-
           :exit, reason
-          when reason == :normal
-          when reason == :shutdown
-          when tuple_size(reason) == 2 and elem(reason, 0) == :shutdown ->
-            send(parent, {self(), {:shutdown, 0}})
+              when reason == :normal
+              when reason == :shutdown
+              when tuple_size(reason) == 2 and elem(reason, 0) == :shutdown ->
+            send parent, {self(), {:shutdown, 0}}
             exit(reason)
-
           kind, reason ->
-            print_error(kind, reason, __STACKTRACE__)
-            send(parent, {self(), {:shutdown, 1}})
-            exit(to_exit(kind, reason, __STACKTRACE__))
+            stack = System.stacktrace
+            print_error(kind, reason, stack)
+            send parent, {self(), {:shutdown, 1}}
+            exit(to_exit(kind, reason, stack))
         else
           _ ->
-            send(parent, {self(), res})
+            send parent, {self(), res}
         end
       end)
 
@@ -150,7 +99,6 @@ defmodule Kernel.CLI do
       {^pid, res} ->
         :erlang.demonitor(ref, [:flush])
         res
-
       {:DOWN, ^ref, _, _, other} ->
         print_error({:EXIT, pid}, other, [])
         {:shutdown, 1}
@@ -166,39 +114,18 @@ defmodule Kernel.CLI do
       {[h | hs], _} when h == hd(list) ->
         new_config = %{config | errors: ["#{h} : Unknown option" | config.errors]}
         callback.(hs, new_config)
-
       {new_list, new_config} ->
         callback.(new_list, new_config)
     end
   end
 
-  ## Error handling
-
-  defp print_error(kind, reason, stacktrace) do
-    IO.write(:stderr, format_error(kind, reason, stacktrace))
+  defp print_error(kind, reason, trace) do
+    IO.puts :stderr, Exception.format(kind, reason, prune_stacktrace(trace))
   end
 
-  defp blame_match(%{match?: true, node: node}), do: blame_ansi(:normal, "+", node)
-  defp blame_match(%{match?: false, node: node}), do: blame_ansi(:red, "-", node)
-
-  defp blame_ansi(color, no_ansi, node) do
-    if IO.ANSI.enabled?() do
-      [color | Macro.to_string(node)]
-      |> IO.ANSI.format(true)
-      |> IO.iodata_to_binary()
-    else
-      no_ansi <> Macro.to_string(node) <> no_ansi
-    end
-  end
-
-  defp pad(string) do
-    "    " <> String.replace(string, "\n", "\n    ")
-  end
-
-  @elixir_internals [:elixir, :elixir_aliases, :elixir_expand, :elixir_compiler, :elixir_module] ++
-                      [:elixir_clauses, :elixir_lexical, :elixir_def, :elixir_map, :elixir_locals] ++
-                      [:elixir_erl, :elixir_erl_clauses, :elixir_erl_compiler, :elixir_erl_pass] ++
-                      [Kernel.ErrorHandler, Module.ParallelChecker]
+  @elixir_internals [:elixir, :elixir_exp, :elixir_compiler, :elixir_module, :elixir_clauses,
+                     :elixir_translator, :elixir_expand, :elixir_lexical, :elixir_exp_clauses,
+                     :elixir_def, :elixir_map]
 
   defp prune_stacktrace([{mod, _, _, _} | t]) when mod in @elixir_internals do
     prune_stacktrace(t)
@@ -218,84 +145,65 @@ defmodule Kernel.CLI do
 
   # Parse shared options
 
-  defp warn_standalone(opt) do
-    IO.puts(:stderr, "#{opt} : Standalone options can't be combined with other options")
-  end
-
-  defp parse_shared([opt | _], _config) when opt in @standalone_opts do
-    warn_standalone(opt)
-    System.halt(1)
-  end
-
-  defp parse_shared([opt | t], _config) when opt in ["-v", "--version"] do
-    if function_exported?(IEx, :started?, 0) and IEx.started?() do
-      IO.puts("IEx " <> System.build_info()[:build])
+  defp parse_shared([opt | _t], _config) when opt in ["-v", "--version"] do
+    if function_exported?(IEx, :started?, 0) and IEx.started? do
+      IO.puts "IEx " <> System.build_info[:build]
     else
-      IO.puts(:erlang.system_info(:system_version))
-      IO.puts("Elixir " <> System.build_info()[:build])
+      IO.puts :erlang.system_info(:system_version)
+      IO.puts "Elixir " <> System.build_info[:build]
     end
 
-    t != [] && warn_standalone(opt)
-    System.halt(0)
+    System.halt 0
   end
 
   defp parse_shared(["-pa", h | t], config) do
     paths = expand_code_path(h)
     Enum.each(paths, &:code.add_patha/1)
-    parse_shared(t, %{config | pa: config.pa ++ paths})
+    parse_shared t, %{config | pa: config.pa ++ paths}
   end
 
   defp parse_shared(["-pz", h | t], config) do
     paths = expand_code_path(h)
     Enum.each(paths, &:code.add_pathz/1)
-    parse_shared(t, %{config | pz: config.pz ++ paths})
+    parse_shared t, %{config | pz: config.pz ++ paths}
   end
 
   defp parse_shared(["--app", h | t], config) do
-    parse_shared(t, %{config | commands: [{:app, h} | config.commands]})
+    parse_shared t, %{config | commands: [{:app, h} | config.commands]}
   end
 
   defp parse_shared(["--no-halt" | t], config) do
-    parse_shared(t, %{config | no_halt: true})
+    parse_shared t, %{config | halt: false}
   end
 
   defp parse_shared(["-e", h | t], config) do
-    parse_shared(t, %{config | commands: [{:eval, h} | config.commands]})
-  end
-
-  defp parse_shared(["--eval", h | t], config) do
-    parse_shared(t, %{config | commands: [{:eval, h} | config.commands]})
-  end
-
-  defp parse_shared(["--rpc-eval", node, h | t], config) do
-    node = append_hostname(node)
-    parse_shared(t, %{config | commands: [{:rpc_eval, node, h} | config.commands]})
+    parse_shared t, %{config | commands: [{:eval, h} | config.commands]}
   end
 
   defp parse_shared(["-r", h | t], config) do
-    parse_shared(t, %{config | commands: [{:require, h} | config.commands]})
+    parse_shared t, %{config | commands: [{:require, h} | config.commands]}
   end
 
   defp parse_shared(["-pr", h | t], config) do
-    parse_shared(t, %{config | commands: [{:parallel_require, h} | config.commands]})
+    parse_shared t, %{config | commands: [{:parallel_require, h} | config.commands]}
+  end
+
+  defp parse_shared([erl, _ | t], config) when erl in ["--erl", "--sname", "--name", "--cookie", "--logger-otp-reports", "--logger-sasl-reports"] do
+    parse_shared t, config
+  end
+
+  defp parse_shared([erl | t], config) when erl in ["--detached", "--hidden", "--werl"] do
+    parse_shared t, config
   end
 
   defp parse_shared(list, config) do
     {list, config}
   end
 
-  defp append_hostname(node) do
-    case :string.find(node, "@") do
-      :nomatch -> node <> :string.find(Atom.to_string(node()), "@")
-      _ -> node
-    end
-  end
-
   defp expand_code_path(path) do
     path = Path.expand(path)
-
     case Path.wildcard(path) do
-      [] -> [to_charlist(path)]
+      []   -> [to_charlist(path)]
       list -> Enum.map(list, &to_charlist/1)
     end
   end
@@ -307,11 +215,11 @@ defmodule Kernel.CLI do
   end
 
   defp parse_argv(["+elixirc" | t], config) do
-    parse_compiler(t, config)
+    parse_compiler t, config
   end
 
   defp parse_argv(["+iex" | t], config) do
-    parse_iex(t, config)
+    parse_iex t, config
   end
 
   defp parse_argv(["-S", h | t], config) do
@@ -321,10 +229,9 @@ defmodule Kernel.CLI do
   defp parse_argv([h | t] = list, config) do
     case h do
       "-" <> _ ->
-        shared_option?(list, config, &parse_argv(&1, &2))
-
+        shared_option? list, config, &parse_argv(&1, &2)
       _ ->
-        if List.keymember?(config.commands, :eval, 0) do
+        if Keyword.has_key?(config.commands, :eval) do
           {config, list}
         else
           {%{config | commands: [{:file, h} | config.commands]}, t}
@@ -343,46 +250,36 @@ defmodule Kernel.CLI do
   end
 
   defp parse_compiler(["-o", h | t], config) do
-    parse_compiler(t, %{config | output: h})
+    parse_compiler t, %{config | output: h}
   end
 
   defp parse_compiler(["--no-docs" | t], config) do
-    parse_compiler(t, %{config | compiler_options: [{:docs, false} | config.compiler_options]})
+    parse_compiler t, %{config | compiler_options: [{:docs, false} | config.compiler_options]}
   end
 
   defp parse_compiler(["--no-debug-info" | t], config) do
-    compiler_options = [{:debug_info, false} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+    parse_compiler t, %{config | compiler_options: [{:debug_info, false} | config.compiler_options]}
   end
 
   defp parse_compiler(["--ignore-module-conflict" | t], config) do
-    compiler_options = [{:ignore_module_conflict, true} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+    parse_compiler t, %{config | compiler_options: [{:ignore_module_conflict, true} | config.compiler_options]}
   end
 
   defp parse_compiler(["--warnings-as-errors" | t], config) do
-    compiler_options = [{:warnings_as_errors, true} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+    parse_compiler t, %{config | compiler_options: [{:warnings_as_errors, true} | config.compiler_options]}
   end
 
   defp parse_compiler(["--verbose" | t], config) do
-    parse_compiler(t, %{config | verbose_compile: true})
-  end
-
-  # Private compiler options
-
-  defp parse_compiler(["--profile", "time" | t], config) do
-    parse_compiler(t, %{config | profile: :time})
+    parse_compiler t, %{config | verbose_compile: true}
   end
 
   defp parse_compiler([h | t] = list, config) do
     case h do
       "-" <> _ ->
-        shared_option?(list, config, &parse_compiler(&1, &2))
-
+        shared_option? list, config, &parse_compiler(&1, &2)
       _ ->
         pattern = if File.dir?(h), do: "#{h}/**/*.ex", else: h
-        parse_compiler(t, %{config | compile: [pattern | config.compile]})
+        parse_compiler t, %{config | compile: [pattern | config.compile]}
     end
   end
 
@@ -399,11 +296,11 @@ defmodule Kernel.CLI do
   # This clause is here so that Kernel.CLI does not
   # error out with "unknown option"
   defp parse_iex(["--dot-iex", _ | t], config) do
-    parse_iex(t, config)
+    parse_iex t, config
   end
 
   defp parse_iex([opt, _ | t], config) when opt in ["--remsh"] do
-    parse_iex(t, config)
+    parse_iex t, config
   end
 
   defp parse_iex(["-S", h | t], config) do
@@ -412,8 +309,10 @@ defmodule Kernel.CLI do
 
   defp parse_iex([h | t] = list, config) do
     case h do
-      "-" <> _ -> shared_option?(list, config, &parse_iex(&1, &2))
-      _ -> {%{config | commands: [{:file, h} | config.commands]}, t}
+      "-" <> _ ->
+        shared_option? list, config, &parse_iex(&1, &2)
+      _ ->
+        {%{config | commands: [{:file, h} | config.commands]}, t}
     end
   end
 
@@ -424,32 +323,22 @@ defmodule Kernel.CLI do
   # Process commands
 
   defp process_command({:cookie, h}, _config) do
-    if Node.alive?() do
-      wrapper(fn -> Node.set_cookie(String.to_atom(h)) end)
+    if Node.alive? do
+      wrapper fn -> Node.set_cookie(String.to_atom(h)) end
     else
       {:error, "--cookie : Cannot set cookie if the node is not alive (set --name or --sname)"}
     end
   end
 
   defp process_command({:eval, expr}, _config) when is_binary(expr) do
-    wrapper(fn -> Code.eval_string(expr, []) end)
-  end
-
-  defp process_command({:rpc_eval, node, expr}, _config) when is_binary(expr) do
-    case :rpc.call(String.to_atom(node), __MODULE__, :rpc_eval, [expr]) do
-      :ok -> :ok
-      {:badrpc, {:EXIT, exit}} -> Process.exit(self(), exit)
-      {:badrpc, reason} -> {:error, "--rpc-eval : RPC failed with reason #{inspect(reason)}"}
-      {kind, error, stack} -> :erlang.raise(kind, error, stack)
-    end
+    wrapper fn -> Code.eval_string(expr, []) end
   end
 
   defp process_command({:app, app}, _config) when is_binary(app) do
     case Application.ensure_all_started(String.to_atom(app)) do
       {:error, {app, reason}} ->
-        msg = "--app : Could not start application #{app}: " <> Application.format_error(reason)
-        {:error, msg}
-
+        {:error, "--app : Could not start application #{app}: " <>
+          Application.format_error(reason)}
       {:ok, _} ->
         :ok
     end
@@ -457,7 +346,7 @@ defmodule Kernel.CLI do
 
   defp process_command({:script, file}, _config) when is_binary(file) do
     if exec = find_elixir_executable(file) do
-      wrapper(fn -> Code.require_file(exec) end)
+      wrapper fn -> Code.require_file(exec) end
     else
       {:error, "-S : Could not find executable #{file}"}
     end
@@ -465,7 +354,7 @@ defmodule Kernel.CLI do
 
   defp process_command({:file, file}, _config) when is_binary(file) do
     if File.regular?(file) do
-      wrapper(fn -> Code.require_file(file) end)
+      wrapper fn -> Code.require_file(file) end
     else
       {:error, "No file named #{file}"}
     end
@@ -475,7 +364,7 @@ defmodule Kernel.CLI do
     files = filter_patterns(pattern)
 
     if files != [] do
-      wrapper(fn -> Enum.map(files, &Code.require_file(&1)) end)
+      wrapper fn -> Enum.map files, &Code.require_file(&1) end
     else
       {:error, "-r : No files matched pattern #{pattern}"}
     end
@@ -485,12 +374,7 @@ defmodule Kernel.CLI do
     files = filter_patterns(pattern)
 
     if files != [] do
-      wrapper(fn ->
-        case Kernel.ParallelCompiler.require(files) do
-          {:ok, _, _} -> :ok
-          {:error, _, _} -> exit({:shutdown, 1})
-        end
-      end)
+      wrapper fn -> Kernel.ParallelRequire.files(files) end
     else
       {:error, "-pr : No files matched pattern #{pattern}"}
     end
@@ -503,36 +387,17 @@ defmodule Kernel.CLI do
     case filter_multiple_patterns(patterns) do
       {:ok, []} ->
         {:error, "No files matched provided patterns"}
-
       {:ok, files} ->
-        wrapper(fn ->
+        wrapper fn ->
           Code.compiler_options(config.compiler_options)
-
-          verbose_opts =
+          opts =
             if config.verbose_compile do
-              [each_file: &IO.puts("Compiling #{Path.relative_to_cwd(&1)}")]
-            else
-              [
-                each_long_compilation:
-                  &IO.puts("Compiling #{Path.relative_to_cwd(&1)} (it's taking more than 10s)")
-              ]
-            end
-
-          profile_opts =
-            if config.profile do
-              [profile: config.profile]
+              [each_long_compilation: &IO.puts("Compiling #{&1} (it's taking more than 5s)")]
             else
               []
             end
-
-          opts = verbose_opts ++ profile_opts
-
-          case Kernel.ParallelCompiler.compile_to_path(files, config.output, opts) do
-            {:ok, _, _} -> :ok
-            {:error, _, _} -> exit({:shutdown, 1})
-          end
-        end)
-
+          Kernel.ParallelCompiler.files_to_path(files, config.output, opts)
+        end
       {:missing, missing} ->
         {:error, "No files matched pattern(s) #{Enum.join(missing, ",")}"}
     end
@@ -540,24 +405,31 @@ defmodule Kernel.CLI do
 
   defp filter_patterns(pattern) do
     pattern
-    |> Path.expand()
-    |> Path.wildcard()
-    |> :lists.usort()
+    |> Path.wildcard
+    |> :lists.usort
     |> Enum.filter(&File.regular?/1)
   end
 
   defp filter_multiple_patterns(patterns) do
-    {files, missing} =
-      Enum.reduce(patterns, {[], []}, fn pattern, {files, missing} ->
-        case filter_patterns(pattern) do
-          [] -> {files, [pattern | missing]}
-          match -> {match ++ files, missing}
-        end
-      end)
+    matched_files = Enum.map patterns, fn(pattern) ->
+      case filter_patterns(pattern) do
+        []    -> {:missing, pattern}
+        files -> {:ok, files}
+      end
+    end
 
-    case missing do
-      [] -> {:ok, :lists.usort(files)}
-      _ -> {:missing, :lists.usort(missing)}
+    files = Enum.filter_map matched_files,
+       fn(match) -> elem(match, 0) == :ok end,
+       &elem(&1, 1)
+
+    missing_patterns = Enum.filter_map matched_files,
+       fn(match) -> elem(match, 0) == :missing end,
+       &elem(&1, 1)
+
+    if missing_patterns == [] do
+      {:ok, :lists.usort(Enum.concat(files))}
+    else
+      {:missing, :lists.usort(missing_patterns)}
     end
   end
 
@@ -575,7 +447,6 @@ defmodule Kernel.CLI do
         {:win32, _} ->
           base = Path.rootname(exec)
           if File.regular?(base), do: base, else: exec
-
         _ ->
           exec
       end

lib/elixir/lib/kernel/error_handler.ex

@@ -5,13 +5,13 @@ defmodule Kernel.ErrorHandler do
 
   @spec undefined_function(module, atom, list) :: term
   def undefined_function(module, fun, args) do
-    ensure_loaded(module) or ensure_compiled(module, :module, :raise)
+    ensure_loaded(module) or ensure_compiled(module, :module)
     :error_handler.undefined_function(module, fun, args)
   end
 
   @spec undefined_lambda(module, fun, list) :: term
   def undefined_lambda(module, fun, args) do
-    ensure_loaded(module) or ensure_compiled(module, :module, :raise)
+    ensure_loaded(module) or ensure_compiled(module, :module)
     :error_handler.undefined_lambda(module, fun, args)
   end
 
@@ -23,21 +23,20 @@ defmodule Kernel.ErrorHandler do
     end
   end
 
-  @spec ensure_compiled(module, atom, atom) :: :found | :not_found | :deadlock
+  @spec ensure_compiled(module, atom) :: boolean
   # Never wait on nil because it should never be defined.
-  def ensure_compiled(nil, _kind, _deadlock) do
-    :not_found
+  def ensure_compiled(nil, _kind) do
+    false
   end
 
-  def ensure_compiled(module, kind, deadlock) do
-    {compiler_pid, file_pid} = :erlang.get(:elixir_compiler_info)
-    ref = :erlang.make_ref()
-    modules = :elixir_module.compiler_modules()
-    send(compiler_pid, {:waiting, kind, self(), ref, file_pid, module, modules, deadlock})
+  def ensure_compiled(module, kind) do
+    parent = :erlang.get(:elixir_compiler_pid)
+    ref    = :erlang.make_ref
+    send parent, {:waiting, kind, self(), ref, module, :elixir_module.compiler_modules()}
     :erlang.garbage_collect(self())
-
     receive do
-      {^ref, value} -> value
+      {^ref, :found}     -> true
+      {^ref, :not_found} -> false
     end
   end
 end

lib/elixir/lib/kernel/lexical_tracker.ex

@@ -6,32 +6,49 @@
 # any of the `GenServer.Behaviour` conveniences.
 defmodule Kernel.LexicalTracker do
   @moduledoc false
-  @timeout :infinity
+  @timeout 30_000
   @behaviour :gen_server
 
   @doc """
-  Returns all references in this lexical scope.
+  Returns all remotes referenced in this lexical scope.
   """
-  def references(pid) do
-    :gen_server.call(pid, :references, @timeout)
+  def remote_references(arg) do
+    :gen_server.call(to_pid(arg), :remote_references, @timeout)
+  end
+
+  @doc """
+  Returns all remote dispatches in this lexical scope.
+  """
+  def remote_dispatches(arg) do
+    :gen_server.call(to_pid(arg), :remote_dispatches, @timeout)
+  end
+
+  @doc """
+  Gets the destination the lexical scope is meant to
+  compile to.
+  """
+  def dest(arg) do
+    :gen_server.call(to_pid(arg), :dest, @timeout)
+  end
+
+  defp to_pid(pid) when is_pid(pid),  do: pid
+  defp to_pid(mod) when is_atom(mod) do
+    table = :elixir_module.data_table(mod)
+    [{_, val}] = :ets.lookup(table, {:elixir, :lexical_tracker})
+    val
   end
 
   # Internal API
 
   # Starts the tracker and returns its PID.
   @doc false
-  def start_link() do
-    :gen_server.start_link(__MODULE__, :ok, [])
+  def start_link(dest) do
+    :gen_server.start_link(__MODULE__, dest, [])
   end
 
   @doc false
   def stop(pid) do
-    :gen_server.call(pid, :stop)
-  end
-
-  @doc false
-  def add_require(pid, module) when is_atom(module) do
-    :gen_server.cast(pid, {:add_require, module})
+    :gen_server.cast(pid, :stop)
   end
 
   @doc false
@@ -45,13 +62,18 @@ defmodule Kernel.LexicalTracker do
   end
 
   @doc false
-  def remote_dispatch(pid, module, mode) when is_atom(module) do
-    :gen_server.cast(pid, {:remote_dispatch, module, mode})
+  def remote_reference(pid, module, mode) when is_atom(module) do
+    :gen_server.cast(pid, {:remote_reference, module, mode})
   end
 
   @doc false
-  def import_dispatch(pid, module, fa, mode) when is_atom(module) do
-    :gen_server.cast(pid, {:import_dispatch, module, fa, mode})
+  def remote_dispatch(pid, module, fa, line, mode) when is_atom(module) do
+    :gen_server.cast(pid, {:remote_dispatch, module, fa, line, mode})
+  end
+
+  @doc false
+  def import_dispatch(pid, module, fa, line, mode) when is_atom(module) do
+    :gen_server.cast(pid, {:import_dispatch, module, fa, line, mode})
   end
 
   @doc false
@@ -59,33 +81,6 @@ defmodule Kernel.LexicalTracker do
     :gen_server.cast(pid, {:alias_dispatch, module})
   end
 
-  @doc false
-  def add_compile_env(pid, app, path, return) do
-    :gen_server.cast(pid, {:compile_env, app, path, return})
-  end
-
-  @doc false
-  def set_file(pid, file) do
-    :gen_server.cast(pid, {:set_file, file})
-  end
-
-  @doc false
-  def reset_file(pid) do
-    :gen_server.cast(pid, :reset_file)
-  end
-
-  @doc false
-  def write_cache(pid, value) do
-    key = :erlang.unique_integer()
-    :gen_server.cast(pid, {:write_cache, key, value})
-    key
-  end
-
-  @doc false
-  def read_cache(pid, key) do
-    :gen_server.call(pid, {:read_cache, key}, @timeout)
-  end
-
   @doc false
   def collect_unused_imports(pid) do
     unused(pid, :import)
@@ -102,53 +97,49 @@ defmodule Kernel.LexicalTracker do
 
   # Callbacks
 
-  def init(:ok) do
-    state = %{
-      directives: %{},
-      references: %{},
-      exports: %{},
-      cache: %{},
-      compile_env: :ordsets.new(),
-      file: nil
-    }
-
-    {:ok, state}
+  def init(dest) do
+    {:ok, %{directives: %{}, references: %{}, compile: %{},
+            runtime: %{}, dest: dest}}
   end
 
   @doc false
   def handle_call({:unused, tag}, _from, state) do
     directives =
-      for {{^tag, module_or_mfa}, marker} <- state.directives, is_integer(marker) do
-        {module_or_mfa, marker}
-      end
+      for {{^tag, module_or_mfa}, marker} <- state.directives,
+          is_integer(marker),
+          do: {module_or_mfa, marker}
 
     {:reply, Enum.sort(directives), state}
   end
 
-  def handle_call(:references, _from, state) do
-    {compile, runtime} = partition(Map.to_list(state.references), [], [])
-    {:reply, {compile, Map.keys(state.exports), runtime, state.compile_env}, state}
+  def handle_call(:remote_references, _from, state) do
+    {:reply, partition(Enum.to_list(state.references), [], []), state}
   end
 
-  def handle_call({:read_cache, key}, _from, %{cache: cache} = state) do
-    {:reply, Map.get(cache, key), state}
+  def handle_call(:remote_dispatches, _from, state) do
+    {:reply, {state.compile, state.runtime}, state}
   end
 
-  def handle_call(:stop, _from, state) do
-    {:stop, :normal, :ok, state}
+  def handle_call(:dest, _from, state) do
+    {:reply, state.dest, state}
   end
 
-  def handle_cast({:write_cache, key, value}, %{cache: cache} = state) do
-    {:noreply, %{state | cache: Map.put(cache, key, value)}}
+  def handle_cast({:remote_reference, module, mode}, state) do
+    {:noreply, %{state | references: add_reference(state.references, module, mode)}}
   end
 
-  def handle_cast({:remote_dispatch, module, mode}, state) do
+  def handle_cast({:remote_dispatch, module, fa, line, mode}, state) do
     references = add_reference(state.references, module, mode)
+    state = add_remote_dispatch(state, module, fa, line, mode)
     {:noreply, %{state | references: references}}
   end
 
-  def handle_cast({:import_dispatch, module, {function, arity}, mode}, state) do
-    state = add_import_dispatch(state, module, function, arity, mode)
+  def handle_cast({:import_dispatch, module, {function, arity} = fa, line, mode}, state) do
+    state =
+      state
+      |> add_import_dispatch(module, function, arity)
+      |> add_remote_dispatch(module, fa, line, mode)
+
     {:noreply, state}
   end
 
@@ -156,28 +147,11 @@ defmodule Kernel.LexicalTracker do
     {:noreply, %{state | directives: add_dispatch(state.directives, module, :alias)}}
   end
 
-  def handle_cast({:set_file, file}, state) do
-    {:noreply, %{state | file: file}}
-  end
-
-  def handle_cast(:reset_file, state) do
-    {:noreply, %{state | file: nil}}
-  end
-
-  def handle_cast({:compile_env, app, path, return}, state) do
-    {:noreply, update_in(state.compile_env, &:ordsets.add_element({app, path, return}, &1))}
-  end
-
-  def handle_cast({:add_require, module}, state) do
-    {:noreply, put_in(state.exports[module], true)}
-  end
-
   def handle_cast({:add_import, module, fas, line, warn}, state) do
-    to_remove = for {{:import, {^module, _, _}} = key, _} <- state.directives, do: key
-
     directives =
       state.directives
-      |> Map.drop(to_remove)
+      |> Enum.reject(&match?({{:import, {^module, _, _}}, _}, &1))
+      |> :maps.from_list
       |> add_directive(module, line, warn, :import)
 
     directives =
@@ -192,6 +166,10 @@ defmodule Kernel.LexicalTracker do
     {:noreply, %{state | directives: add_directive(state.directives, module, line, warn, :alias)}}
   end
 
+  def handle_cast(:stop, state) do
+    {:stop, :normal, state}
+  end
+
   @doc false
   def handle_info(_msg, state) do
     {:noreply, state}
@@ -209,31 +187,34 @@ defmodule Kernel.LexicalTracker do
 
   defp partition([{remote, :compile} | t], compile, runtime),
     do: partition(t, [remote | compile], runtime)
-
   defp partition([{remote, :runtime} | t], compile, runtime),
     do: partition(t, compile, [remote | runtime])
-
-  defp partition([], compile, runtime), do: {compile, runtime}
+  defp partition([], compile, runtime),
+    do: {compile, runtime}
 
   # Callbacks helpers
 
+  defp add_reference(references, module, :runtime) when is_atom(module),
+    do: map_put_new(module, :runtime, references)
   defp add_reference(references, module, :compile) when is_atom(module),
-    do: Map.put(references, module, :compile)
+    do: :maps.put(module, :compile, references)
 
-  defp add_reference(references, module, :runtime) when is_atom(module) do
-    case Map.fetch(references, module) do
-      {:ok, _} -> references
-      :error -> Map.put(references, module, :runtime)
+  defp add_remote_dispatch(state, module, fa, line, mode) when is_atom(module) do
+    map_update mode, %{module => %{fa => [line]}}, state, fn mode_dispatches ->
+      map_update module, %{fa => [line]}, mode_dispatches, fn module_dispatches ->
+        map_update fa, [line], module_dispatches, &[line | List.delete(&1, line)]
+      end
     end
   end
 
-  defp add_import_dispatch(state, module, function, arity, mode) do
+  defp add_import_dispatch(state, module, function, arity) do
     directives =
-      state.directives
-      |> add_dispatch(module, :import)
+      add_dispatch(state.directives, module, :import)
       |> add_dispatch({module, function, arity}, :import)
+    # Always compile time because we depend
+    # on the module at compile time
+    references = add_reference(state.references, module, :compile)
 
-    references = add_reference(state.references, module, mode)
     %{state | directives: directives, references: references}
   end
 
@@ -242,10 +223,24 @@ defmodule Kernel.LexicalTracker do
   # If the value is true, it was imported/aliased and used
   defp add_directive(directives, module_or_mfa, line, warn, tag) do
     marker = if warn, do: line, else: true
-    Map.put(directives, {tag, module_or_mfa}, marker)
+    :maps.put({tag, module_or_mfa}, marker, directives)
   end
 
   defp add_dispatch(directives, module_or_mfa, tag) do
-    Map.put(directives, {tag, module_or_mfa}, true)
+    :maps.put({tag, module_or_mfa}, true, directives)
+  end
+
+  defp map_update(key, initial, map, fun) do
+    case :maps.find(key, map) do
+      {:ok, val} -> :maps.put(key, fun.(val), map)
+      :error -> :maps.put(key, initial, map)
+    end
+  end
+
+  defp map_put_new(key, value, map) do
+    case :maps.find(key, map) do
+      {:ok, _} -> map
+      :error -> :maps.put(key, value, map)
+    end
   end
 end

lib/elixir/lib/kernel/parallel_require.ex

@@ -1,17 +1,109 @@
 defmodule Kernel.ParallelRequire do
-  @moduledoc false
+  @moduledoc """
+  A module responsible for requiring files in parallel.
+  """
 
-  @deprecated "Use Kernel.ParallelCompiler.require/2 instead"
+  @doc """
+  Requires the given files.
+
+  A callback that will be invoked with each file, or a keyword list of `callbacks` can be provided:
+
+    * `:each_file` - invoked with each file
+
+    * `:each_module` - invoked with file, module name, and binary code
+
+  Returns the modules generated by each required file.
+  """
   def files(files, callbacks \\ [])
 
   def files(files, callback) when is_function(callback, 1) do
-    files(files, each_file: callback)
+    files(files, [each_file: callback])
   end
 
-  def files(files, options) when is_list(options) do
-    case Kernel.ParallelCompiler.require(files, options) do
-      {:ok, modules, _} -> modules
-      {:error, _, _} -> exit({:shutdown, 1})
+  def files(files, callbacks) when is_list(callbacks) do
+    compiler_pid = self()
+    :elixir_code_server.cast({:reset_warnings, compiler_pid})
+    schedulers = max(:erlang.system_info(:schedulers_online), 2)
+    result = spawn_requires(files, [], callbacks, schedulers, [])
+
+    # In case --warning-as-errors is enabled and there was a warning,
+    # compilation status will be set to error.
+    case :elixir_code_server.call({:compilation_status, compiler_pid}) do
+      :ok ->
+        result
+      :error ->
+        IO.puts :stderr, "\nExecution failed due to warnings while using the --warnings-as-errors option"
+        exit({:shutdown, 1})
+    end
+  end
+
+  defp spawn_requires([], [], _callbacks, _schedulers, result), do: result
+
+  defp spawn_requires([], waiting, callbacks, schedulers, result) do
+    wait_for_messages([], waiting, callbacks, schedulers, result)
+  end
+
+  defp spawn_requires(files, waiting, callbacks, schedulers, result) when length(waiting) >= schedulers do
+    wait_for_messages(files, waiting, callbacks, schedulers, result)
+  end
+
+  defp spawn_requires([file | files], waiting, callbacks, schedulers, result) do
+    parent = self()
+    {pid, ref} = :erlang.spawn_monitor fn ->
+      :erlang.put(:elixir_compiler_pid, parent)
+      :erlang.put(:elixir_compiler_file, file)
+
+      exit(try do
+        new = Code.require_file(file) || []
+        {:required, Enum.map(new, &elem(&1, 0)), file}
+      catch
+        kind, reason ->
+          {:failure, kind, reason, System.stacktrace}
+      end)
+    end
+
+    spawn_requires(files, [{pid, ref} | waiting], callbacks, schedulers, result)
+  end
+
+  defp wait_for_messages(files, waiting, callbacks, schedulers, result) do
+    receive do
+      {:DOWN, ref, :process, pid, status} ->
+        tuple = {pid, ref}
+        if tuple in waiting do
+          waiting = List.delete(waiting, tuple)
+
+          case status do
+            {:required, mods, file} ->
+              if each_file_callback = callbacks[:each_file] do
+                each_file_callback.(file)
+              end
+
+              spawn_requires(files, waiting, callbacks, schedulers, mods ++ result)
+
+            {:failure, kind, reason, stacktrace} ->
+              :erlang.raise(kind, reason, stacktrace)
+
+            other ->
+              :erlang.raise(:exit, other, [])
+          end
+        else
+          spawn_requires(files, waiting, callbacks, schedulers, result)
+        end
+
+      {:module_available, child, ref, file, module, binary} ->
+        if each_module_callback = callbacks[:each_module] do
+          each_module_callback.(file, module, binary)
+        end
+
+        send(child, {ref, :ack})
+        spawn_requires(files, waiting, callbacks, schedulers, result)
+
+      {:struct_available, _} ->
+        spawn_requires(files, waiting, callbacks, schedulers, result)
+
+      {:waiting, _, child, ref, _, _} ->
+        send(child, {ref, :not_found})
+        spawn_requires(files, waiting, callbacks, schedulers, result)
     end
   end
 end

lib/elixir/lib/kernel/utils.ex

@@ -6,13 +6,10 @@ defmodule Kernel.Utils do
   @doc """
   Callback for destructure.
   """
-  def destructure(list, count)
-      when is_list(list) and is_integer(count) and count >= 0,
-      do: destructure_list(list, count)
-
-  def destructure(nil, count)
-      when is_integer(count) and count >= 0,
-      do: destructure_nil(count)
+  def destructure(list, count) when is_list(list) and is_integer(count) and count >= 0,
+    do: destructure_list(list, count)
+  def destructure(nil, count) when is_integer(count) and count >= 0,
+    do: destructure_nil(count)
 
   defp destructure_list(_, 0), do: []
   defp destructure_list([], count), do: destructure_nil(count)
@@ -25,47 +22,47 @@ defmodule Kernel.Utils do
   Callback for defdelegate.
   """
   def defdelegate(fun, opts) when is_list(opts) do
-    # TODO: Remove on v2.0
-    append_first? = Keyword.get(opts, :append_first, false)
+    # TODO: Remove by 2.0
+    append_first = Keyword.get(opts, :append_first, false)
 
     {name, args} =
-      case fun do
-        {:when, _, [_left, right]} ->
-          raise ArgumentError,
-                "guards are not allowed in defdelegate/2, got: when #{Macro.to_string(right)}"
-
-        _ ->
-          case Macro.decompose_call(fun) do
-            {_, _} = pair -> pair
-            _ -> raise ArgumentError, "invalid syntax in defdelegate #{Macro.to_string(fun)}"
-          end
+      case Macro.decompose_call(fun) do
+        {_, _} = pair -> pair
+        _ -> raise ArgumentError, "invalid syntax in defdelegate #{Macro.to_string(fun)}"
       end
 
+    as_args_list = normalize_args(args)
     as = Keyword.get(opts, :as, name)
-    as_args = build_as_args(args, append_first?)
-
-    {name, args, as, as_args}
+    :lists.map(fn as_args ->
+      formal_args = make_formal_args(as_args)
+      as_args = case append_first do
+        true  -> tl(as_args) ++ [hd(as_args)]
+        false -> as_args
+      end
+      {name, formal_args, as, as_args}
+    end, as_args_list)
   end
 
-  defp build_as_args(args, append_first?) do
-    as_args = :lists.map(&build_as_arg/1, args)
-
-    case append_first? do
-      true -> tl(as_args) ++ [hd(as_args)]
-      false -> as_args
-    end
+  defp make_formal_args(args) do
+    fun = &match?({name, _, mod} when is_atom(name) and is_atom(mod), &1)
+    :lists.filter(fun, args)
   end
 
-  defp build_as_arg({:\\, _, [arg, _default_arg]}), do: validate_arg(arg)
-  defp build_as_arg(arg), do: validate_arg(arg)
-
-  defp validate_arg({name, _, mod} = arg) when is_atom(name) and is_atom(mod) do
-    arg
+  defp normalize_args(raw_args) do
+    :lists.foldr(fn
+      ({:\\, _, [arg, default_arg]}, [as_args | _] = as_args_list) ->
+        new_as_args = [default_arg | as_args]
+        [new_as_args | add_arg(as_args_list, arg)]
+      (arg, as_args_list) ->
+        add_arg(as_args_list, arg)
+    end, [[]], raw_args)
   end
 
-  defp validate_arg(ast) do
+  defp add_arg(as_args_list, {name, _, mod} = arg) when is_atom(name) and is_atom(mod),
+    do: :lists.map(&([arg | &1]), as_args_list)
+  defp add_arg(_, code) do
     raise ArgumentError,
-          "defdelegate/2 only accepts function parameters, got: #{Macro.to_string(ast)}"
+      "defdelegate/2 only accepts function parameters, got: #{Macro.to_string(code)}"
   end
 
   @doc """
@@ -75,12 +72,11 @@ defmodule Kernel.Utils do
     case fields do
       fs when is_list(fs) ->
         :ok
-
       other ->
-        raise ArgumentError, "struct fields definition must be list, got: #{inspect(other)}"
+        raise ArgumentError, "struct fields definition must be list, got: #{inspect other}"
     end
 
-    mapper = fn
+    fields = :lists.map(fn
       {key, val} when is_atom(key) ->
         try do
           Macro.escape(val)
@@ -90,63 +86,24 @@ defmodule Kernel.Utils do
         else
           _ -> {key, val}
         end
-
       key when is_atom(key) ->
         {key, nil}
-
       other ->
-        raise ArgumentError, "struct field names must be atoms, got: #{inspect(other)}"
-    end
+        raise ArgumentError, "struct field names must be atoms, got: #{inspect other}"
+    end, fields)
 
-    fields = :lists.map(mapper, fields)
-    enforce_keys = List.wrap(Module.get_attribute(module, :enforce_keys))
-
-    # TODO: Make it raise on v2.0
-    warn_on_duplicate_struct_key(:lists.keysort(1, fields))
-
-    foreach = fn
-      key when is_atom(key) ->
-        :ok
-
-      key ->
-        raise ArgumentError, "keys given to @enforce_keys must be atoms, got: #{inspect(key)}"
-    end
-
-    :lists.foreach(foreach, enforce_keys)
-
-    struct = :maps.put(:__struct__, module, :maps.from_list(fields))
-
-    case enforce_keys -- :maps.keys(struct) do
-      [] ->
-        {struct, enforce_keys, Module.get_attribute(module, :derive)}
-
-      error_keys ->
-        raise ArgumentError,
-              "@enforce_keys required keys (#{inspect(error_keys)}) that are not defined in defstruct: " <>
-                "#{inspect(fields)}"
-    end
-  end
-
-  defp warn_on_duplicate_struct_key([]) do
-    :ok
-  end
-
-  defp warn_on_duplicate_struct_key([{key, _} | [{key, _} | _] = rest]) do
-    IO.warn("duplicate key #{inspect(key)} found in struct")
-    warn_on_duplicate_struct_key(rest)
-  end
-
-  defp warn_on_duplicate_struct_key([_ | rest]) do
-    warn_on_duplicate_struct_key(rest)
+    {:maps.put(:__struct__, module, :maps.from_list(fields)),
+     List.wrap(Module.get_attribute(module, :enforce_keys)),
+     Module.get_attribute(module, :derive)}
   end
 
   @doc """
   Announcing callback for defstruct.
   """
   def announce_struct(module) do
-    case :erlang.get(:elixir_compiler_info) do
+    case :erlang.get(:elixir_compiler_pid) do
       :undefined -> :ok
-      {pid, _} -> send(pid, {:available, :struct, module})
+      pid -> send(pid, {:struct_available, module})
     end
   end
 
@@ -156,158 +113,14 @@ defmodule Kernel.Utils do
   def raise(msg) when is_binary(msg) do
     RuntimeError.exception(msg)
   end
-
-  def raise(module) when is_atom(module) do
-    module.exception([])
+  def raise(atom) when is_atom(atom) do
+    atom.exception([])
   end
-
-  def raise(%_{__exception__: true} = exception) do
+  def raise(%{__struct__: struct, __exception__: true} = exception) when is_atom(struct) do
     exception
   end
-
   def raise(other) do
-    ArgumentError.exception(
-      "raise/1 and reraise/2 expect a module name, string or exception " <>
-        "as the first argument, got: #{inspect(other)}"
-    )
-  end
-
-  @doc """
-  Callback for defguard.
-
-  Rewrites an expression so it can be used both inside and outside a guard.
-
-  Take, for example, the expression:
-
-      is_integer(value) and rem(value, 2) == 0
-
-  If we wanted to create a macro, `is_even`, from this expression, that could be
-  used in guards, we'd have to take several things into account.
-
-  First, if this expression is being used inside a guard, `value` needs to be
-  unquoted each place it occurs, since it has not yet been at that point in our
-  macro.
-
-  Secondly, if the expression is being used outside of a guard, we want to unquote
-  `value`, but only once, and then re-use the unquoted form throughout the expression.
-
-  This helper does exactly that: takes the AST for an expression and a list of
-  variable references it should be aware of, and rewrites it into a new expression
-  that checks for its presence in a guard, then unquotes the variable references as
-  appropriate.
-
-  The following code
-
-      expression = quote do: is_integer(value) and rem(value, 2) == 0
-      variable_references = [value: Elixir]
-      Kernel.Utils.defguard(expression, variable_references) |> Macro.to_string() |> IO.puts()
-
-  would print a code similar to:
-
-      case Macro.Env.in_guard?(__CALLER__) do
-        true ->
-          quote do
-            is_integer(unquote(value)) and rem(unquote(value), 2) == 0
-          end
-
-        false ->
-          quote do
-            value = unquote(value)
-            is_integer(value) and rem(value, 2) == 0
-          end
-      end
-
-  """
-  defmacro defguard(args, expr) do
-    defguard(args, expr, __CALLER__)
-  end
-
-  @spec defguard([Macro.t()], Macro.t(), Macro.Env.t()) :: Macro.t()
-  def defguard(args, expr, env) do
-    {^args, vars} = extract_refs_from_args(args)
-    env = :elixir_env.with_vars(%{env | context: :guard}, vars)
-    {expr, _, _} = :elixir_expand.expand(expr, :elixir_env.env_to_ex(env), env)
-
-    quote do
-      case Macro.Env.in_guard?(__CALLER__) do
-        true -> unquote(literal_quote(unquote_every_ref(expr, vars)))
-        false -> unquote(literal_quote(unquote_refs_once(expr, vars)))
-      end
-    end
-  end
-
-  defp extract_refs_from_args(args) do
-    Macro.postwalk(args, [], fn
-      {ref, meta, context} = var, acc when is_atom(ref) and is_atom(context) ->
-        {var, [{ref, var_context(meta, context)} | acc]}
-
-      node, acc ->
-        {node, acc}
-    end)
-  end
-
-  # Finds every reference to `refs` in `guard` and wraps them in an unquote.
-  defp unquote_every_ref(guard, refs) do
-    Macro.postwalk(guard, fn
-      {ref, meta, context} = var when is_atom(ref) and is_atom(context) ->
-        case {ref, var_context(meta, context)} in refs do
-          true -> literal_unquote(var)
-          false -> var
-        end
-
-      node ->
-        node
-    end)
-  end
-
-  # Prefaces `guard` with unquoted versions of `refs`.
-  defp unquote_refs_once(guard, refs) do
-    {guard, used_refs} =
-      Macro.postwalk(guard, %{}, fn
-        {ref, meta, context} = var, acc when is_atom(ref) and is_atom(context) ->
-          pair = {ref, var_context(meta, context)}
-
-          case pair in refs do
-            true ->
-              case acc do
-                %{^pair => {new_var, _}} ->
-                  {new_var, acc}
-
-                %{} ->
-                  generated = String.to_atom("arg" <> Integer.to_string(map_size(acc) + 1))
-                  new_var = Macro.var(generated, Elixir)
-                  {new_var, Map.put(acc, pair, {new_var, var})}
-              end
-
-            false ->
-              {var, acc}
-          end
-
-        node, acc ->
-          {node, acc}
-      end)
-
-    all_used = for ref <- :lists.reverse(refs), used = :maps.get(ref, used_refs, nil), do: used
-    {vars, exprs} = :lists.unzip(all_used)
-
-    quote do
-      {unquote_splicing(vars)} = {unquote_splicing(Enum.map(exprs, &literal_unquote/1))}
-      unquote(guard)
-    end
-  end
-
-  defp literal_quote(ast) do
-    {:quote, [], [[do: ast]]}
-  end
-
-  defp literal_unquote(ast) do
-    {:unquote, [], List.wrap(ast)}
-  end
-
-  defp var_context(meta, kind) do
-    case :lists.keyfind(:counter, 1, meta) do
-      {:counter, counter} -> counter
-      false -> kind
-    end
+    ArgumentError.exception("raise/1 expects an alias, string or exception as " <>
+                            "the first argument, got: #{inspect other}")
   end
 end

lib/elixir/lib/list/chars.ex

@@ -1,31 +1,24 @@
 defprotocol List.Chars do
   @moduledoc ~S"""
-  The `List.Chars` protocol is responsible for
-  converting a structure to a charlist (only if applicable).
-
-  The only function that must be implemented is
-  `to_charlist/1` which does the conversion.
+  The List.Chars protocol is responsible for
+  converting a structure to a list (only if applicable).
+  The only function required to be implemented is
+  `to_charlist` which does the conversion.
 
   The `to_charlist/1` function automatically imported
   by `Kernel` invokes this protocol.
   """
 
-  @doc """
-  Converts `term` to a charlist.
-  """
-  @spec to_charlist(t) :: charlist
   def to_charlist(term)
 
+  # TODO: Deprecate by v1.5
   @doc false
-  @deprecated "Use List.Chars.to_charlist/1 instead"
   Kernel.def to_char_list(term) do
     __MODULE__.to_charlist(term)
   end
 end
 
 defimpl List.Chars, for: Atom do
-  def to_charlist(nil), do: ''
-
   def to_charlist(atom), do: Atom.to_charlist(atom)
 end
 
@@ -39,9 +32,9 @@ defimpl List.Chars, for: BitString do
 
   def to_charlist(term) do
     raise Protocol.UndefinedError,
-      protocol: @protocol,
-      value: term,
-      description: "cannot convert a bitstring to a charlist"
+             protocol: @protocol,
+                value: term,
+          description: "cannot convert a bitstring to a charlist"
   end
 end
 

lib/elixir/lib/macro/env.ex

@@ -21,253 +21,91 @@ defmodule Macro.Env do
 
   It contains the following fields:
 
-    * `context` - the context of the environment; it can be `nil`
-      (default context), `:guard` (inside a guard) or `:match` (inside a match)
-    * `context_modules` - a list of modules defined in the current context
+    * `module` - the current module name
     * `file` - the current file name as a binary
+    * `line` - the current line as an integer
     * `function` - a tuple as `{atom, integer}`, where the first
       element is the function name and the second its arity; returns
       `nil` if not inside a function
-    * `line` - the current line as an integer
-    * `module` - the current module name
-
-  The following fields are private to Elixir's macro expansion mechanism and
-  must not be accessed directly:
-
-    * `aliases`
-    * `functions`
-    * `macro_aliases`
-    * `macros`
-    * `lexical_tracker`
-    * `requires`
-    * `tracers`
-    * `versioned_vars`
-
+    * `context` - the context of the environment; it can be `nil`
+      (default context), inside a guard or inside a match
+    * `aliases` -  a list of two-element tuples, where the first
+      element is the aliased name and the second one the actual name
+    * `requires` - the list of required modules
+    * `functions` - a list of functions imported from each module
+    * `macros` - a list of macros imported from each module
+    * `macro_aliases` - a list of aliases defined inside the current macro
+    * `context_modules` - a list of modules defined in the current context
+    * `vars` - a list keeping all defined variables as `{var, context}`
+    * `export_vars` - a list keeping all variables to be exported in a
+      construct (may be `nil`)
+    * `lexical_tracker` - PID of the lexical tracker which is responsible for
+      keeping user info
   """
 
-  @type context :: :match | :guard | nil
-  @type context_modules :: [module]
+  @type name_arity :: {atom, arity}
   @type file :: binary
   @type line :: non_neg_integer
-  @type name_arity :: {atom, arity}
-  @type variable :: {atom, atom | term}
+  @type aliases :: [{module, module}]
+  @type macro_aliases :: [{module, {integer, module}}]
+  @type context :: :match | :guard | nil
+  @type requires :: [module]
+  @type functions :: [{module, [name_arity]}]
+  @type macros :: [{module, [name_arity]}]
+  @type context_modules :: [module]
+  @type vars :: [{atom, atom | non_neg_integer}]
+  @type export_vars :: vars | nil
+  @type lexical_tracker :: pid
+  @type local :: atom | nil
 
-  @typep aliases :: [{module, module}]
-  @typep functions :: [{module, [name_arity]}]
-  @typep lexical_tracker :: pid | nil
-  @typep macro_aliases :: [{module, {term, module}}]
-  @typep macros :: [{module, [name_arity]}]
-  @typep requires :: [module]
-  @typep tracers :: [module]
-  @typep versioned_vars :: %{optional(variable) => var_version :: non_neg_integer}
+  @type t :: %{__struct__: __MODULE__,
+               module: atom,
+               file: file,
+               line: line,
+               function: name_arity | nil,
+               context: context,
+               requires: requires,
+               aliases: aliases,
+               functions: functions,
+               macros: macros,
+               macro_aliases: aliases,
+               context_modules: context_modules,
+               vars: vars,
+               export_vars: export_vars,
+               lexical_tracker: lexical_tracker}
 
-  @type t :: %{
-          __struct__: __MODULE__,
-          aliases: aliases,
-          context: context,
-          context_modules: context_modules,
-          file: file,
-          function: name_arity | nil,
-          functions: functions,
-          lexical_tracker: lexical_tracker,
-          line: line,
-          macro_aliases: macro_aliases,
-          macros: macros,
-          module: module,
-          requires: requires,
-          tracers: tracers,
-          versioned_vars: versioned_vars
-        }
-
-  # Define the __struct__ callbacks by hand for bootstrap reasons.
-  @doc false
   def __struct__ do
-    %{
-      __struct__: __MODULE__,
-      aliases: [],
-      context: nil,
-      context_modules: [],
-      file: "nofile",
-      function: nil,
-      functions: [],
-      lexical_tracker: nil,
-      line: 0,
-      macro_aliases: [],
-      macros: [],
+    %{__struct__: __MODULE__,
       module: nil,
+      file: "nofile",
+      line: 0,
+      function: nil,
+      context: nil,
       requires: [],
-      tracers: [],
-      versioned_vars: %{}
-    }
+      aliases: [],
+      functions: [],
+      macros: [],
+      macro_aliases: [],
+      context_modules: [],
+      vars: [],
+      export_vars: nil,
+      lexical_tracker: nil}
   end
 
-  @doc false
   def __struct__(kv) do
-    Enum.reduce(kv, __struct__(), fn {k, v}, acc -> :maps.update(k, v, acc) end)
-  end
-
-  @doc """
-  Returns a list of variables in the current environment.
-
-  Each variable is identified by a tuple of two elements,
-  where the first element is the variable name as an atom
-  and the second element is its context, which may be an
-  atom or an integer.
-  """
-  @doc since: "1.7.0"
-  @spec vars(t) :: [variable]
-  def vars(env)
-
-  def vars(%{__struct__: Macro.Env, versioned_vars: vars}) do
-    Map.keys(vars)
-  end
-
-  @doc """
-  Checks if a variable belongs to the environment.
-
-  ## Examples
-
-      iex> x = 13
-      iex> x
-      13
-      iex> Macro.Env.has_var?(__ENV__, {:x, nil})
-      true
-      iex> Macro.Env.has_var?(__ENV__, {:unknown, nil})
-      false
-
-  """
-  @doc since: "1.7.0"
-  @spec has_var?(t, variable) :: boolean()
-  def has_var?(env, var)
-
-  def has_var?(%{__struct__: Macro.Env, versioned_vars: vars}, var) do
-    Map.has_key?(vars, var)
+    Enum.reduce kv, __struct__(), fn {k, v}, acc -> :maps.update(k, v, acc) end
   end
 
   @doc """
   Returns a keyword list containing the file and line
   information as keys.
   """
-  @spec location(t) :: keyword
+  @spec location(t) :: Keyword.t
   def location(env)
-
   def location(%{__struct__: Macro.Env, file: file, line: line}) do
     [file: file, line: line]
   end
 
-  @doc """
-  Fetches the alias for the given atom.
-
-  Returns `{:ok, alias}` if the alias exists, `:error` 
-  otherwise.
-
-  ## Examples
-
-      iex> alias Foo.Bar, as: Baz
-      iex> Baz
-      Foo.Bar
-      iex> Macro.Env.fetch_alias(__ENV__, :Baz)
-      {:ok, Foo.Bar}
-      iex> Macro.Env.fetch_alias(__ENV__, :Unknown)
-      :error
-
-  """
-  @doc since: "1.13.0"
-  @spec fetch_alias(t, atom) :: {:ok, atom} | :error
-  def fetch_alias(%{__struct__: Macro.Env, aliases: aliases}, atom) when is_atom(atom),
-    do: Keyword.fetch(aliases, :"Elixir.#{atom}")
-
-  @doc """
-  Fetches the macro alias for the given atom.
-
-  Returns `{:ok, macro_alias}` if the alias exists, `:error`
-  otherwise.
-
-  A macro alias is only used inside quoted expansion. See
-  `fetch_alias/2` for a more general example.
-  """
-  @doc since: "1.13.0"
-  @spec fetch_macro_alias(t, atom) :: {:ok, atom} | :error
-  def fetch_macro_alias(%{__struct__: Macro.Env, macro_aliases: aliases}, atom)
-      when is_atom(atom),
-      do: Keyword.fetch(aliases, :"Elixir.#{atom}")
-
-  @doc """
-  Returns the modules from which the given `{name, arity}` was
-  imported.
-
-  It returns a list of two element tuples in the shape of
-  `{:function | :macro, module}`. The elements in the list
-  are in no particular order and the order is not guaranteed.
-
-  ## Examples
-
-      iex> Macro.Env.lookup_import(__ENV__, {:duplicate, 2})
-      []
-      iex> import Tuple, only: [duplicate: 2], warn: false
-      iex> Macro.Env.lookup_import(__ENV__, {:duplicate, 2})
-      [{:function, Tuple}]
-      iex> import List, only: [duplicate: 2], warn: false
-      iex> Macro.Env.lookup_import(__ENV__, {:duplicate, 2})
-      [{:function, List}, {:function, Tuple}]
-
-      iex> Macro.Env.lookup_import(__ENV__, {:def, 1})
-      [{:macro, Kernel}]
-
-  """
-  @doc since: "1.13.0"
-  @spec lookup_import(t, name_arity) :: [{:function | :macro, module}]
-  def lookup_import(
-        %{__struct__: Macro.Env, functions: functions, macros: macros},
-        {name, arity} = pair
-      )
-      when is_atom(name) and is_integer(arity) do
-    f = for {mod, pairs} <- functions, :ordsets.is_element(pair, pairs), do: {:function, mod}
-    m = for {mod, pairs} <- macros, :ordsets.is_element(pair, pairs), do: {:macro, mod}
-    f ++ m
-  end
-
-  @doc """
-  Returns true if the given module has been required.
-
-  ## Examples
-
-      iex> Macro.Env.required?(__ENV__, Integer)
-      false
-      iex> require Integer
-      iex> Macro.Env.required?(__ENV__, Integer)
-      true
-
-      iex> Macro.Env.required?(__ENV__, Kernel)
-      true
-  """
-  @doc since: "1.13.0"
-  @spec required?(t, module) :: boolean
-  def required?(%{__struct__: Macro.Env, requires: requires}, mod) when is_atom(mod),
-    do: mod in requires
-
-  @doc """
-  Prepend a tracer to the list of tracers in the environment.
-
-  ## Examples
-
-      Macro.Env.prepend_tracer(__ENV__, MyCustomTracer)
-
-  """
-  @doc since: "1.13.0"
-  @spec prepend_tracer(t, module) :: t
-  def prepend_tracer(%{__struct__: Macro.Env, tracers: tracers} = env, tracer) do
-    %{env | tracers: [tracer | tracers]}
-  end
-
-  @doc """
-  Returns a `Macro.Env` in the match context.
-  """
-  @spec to_match(t) :: t
-  def to_match(%{__struct__: Macro.Env} = env) do
-    %{env | context: :match}
-  end
-
   @doc """
   Returns whether the compilation environment is currently
   inside a guard.
@@ -292,10 +130,8 @@ defmodule Macro.Env do
     cond do
       is_nil(env.module) ->
         [{:elixir_compiler, :__FILE__, 1, relative_location(env)}]
-
       is_nil(env.function) ->
         [{env.module, :__MODULE__, 0, relative_location(env)}]
-
       true ->
         {name, arity} = env.function
         [{env.module, name, arity, relative_location(env)}]
@@ -303,6 +139,6 @@ defmodule Macro.Env do
   end
 
   defp relative_location(env) do
-    [file: String.to_charlist(Path.relative_to_cwd(env.file)), line: env.line]
+    [file: Path.relative_to_cwd(env.file), line: env.line]
   end
 end