Update CHANGELOG.md

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 +1,15 @@
+language: erlang
+
+otp_release:
+  - 18.0
+
+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

@@ -1,307 +1,282 @@
-# Changelog for Elixir v1.13
+# Changelog for Elixir v1.2
 
-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.
+v1.2 brings enhancements, bug fixes, performance improvements and more
+into Elixir. Elixir v1.2 relies on many features in Erlang 18, requiring
+at least Erlang 18+. Upgrading to Erlang 18 is therefore necessary before
+upgrading Elixir.
 
-## Semantic recompilation
+## Erlang 18 support
 
-Elixir v1.13 comes with many improvements to the compiler, so it recompiles your files less frequently. In particular:
+We have brought many features specific to Erlang 18. Here are the highlights:
 
-  * The digest of the files are considered in addition to their size. This avoids recompiling many files when switching or rebasing branches.
+  * Maps can now scale from dozens to millions of keys. Therefore, usage of
+    the modules `Dict` and `HashDict` is now discouraged and will be
+    deprecated in future releases, instead use `Map`. Similarly, `Set` and
+    `HashSet` will be deprecated in favor of `MapSet`
+  * Compilation times are faster due to improvements in both the Elixir and
+    Erlang compilers
+  * Dialyzer now emits less false negative warnings thanks to new annotations
+    available in the Erlang compiler
 
-  * 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`).
+## Language improvements
 
-  * 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.
+This release includes four notable language improvements:
 
-  * Adding, updating or removing a dependency now only recompiles the project files that depend on the modified a dependency.
+  * The addition of multi aliases/imports/require:
 
-  * If your project has both Erlang and Elixir files, changing an Erlang file will now recompile only the Elixir files that depend on it.
+        alias MyApp.{Foo, Bar, Baz}
 
-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:
+  * Support for variables in map keys:
 
-  * you change the compilation options in `mix.exs`
-  * you change the configuration for the current project in `config/config.exs`
+        %{key => value}
 
-## mix xref
+  * Support for the pin operator in map keys and function clauses:
 
-`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.
+        %{^key => value} = %{key => value}
+        fn ^key -> :ok end
 
-Elixir v1.13 comes with many improvements to `mix xref`, such as:
+  * Addition of the `with` special form to match on multiple expressions:
 
-  * `mix xref graph` now supports `--label` to be set to "compile-connected", which returns all compile-time dependencies that lead to additional transitive dependencies.
+        with {:ok, contents} <- File.read("my_file.ex"),
+             {res, binding} <- Code.eval_string(contents),
+             do: {:ok, res}
 
-  * 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).
+These improvements aim to make the language more consistent and expressive.
 
-  * 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.
+## Getting started experience
 
-  * `mix xref graph` now supports multiple `--sink` and `--source` to be given.
+While we were improving the language, we also improved both the parser and
+compiler to be even more aware of language constructs, emitting warnings
+on common pitfalls like when piping to expressions without parentheses or
+when defining unsafe variables.
 
-With these improvements, it has become simpler to understand the impact code recompilation has in our codebases and how to limit it.
+We have also introduced the `i/1` helper in IEx, which allows developers
+to retrieve information about any data type. This will help newcomers
+explore the language values while providing experienced developers with
+crucial information about the value they are introspecting.
 
-## Code fragments
+## Workflow improvements
 
-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.
+Umbrella applications are now able to share both build and configuration files.
+This aims to drastically reduce compilation times in umbrella projects by
+adding the following configuration to each umbrella app's `mix.exs` file:
 
-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:
+    build_path: "../../_build",
+    config_path: "../../config/config.exs",
 
-```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)
+Finally, Mix will now consolidate protocols by default as we are now able to
+consolidate in parallel and cache the consolidation results, providing the
+best performance across all environments without affecting compilation times.
+The only downside of this change is that, if you have been implementing
+protocols exclusively as part of your test suite, inside the `test` directory,
+those won't be picked up as it happens after compilation. For such cases,
+consolidation can be disabled by setting `consolidate_protocols: false` in
+the project config.
 
-```
+These are great additions on top of the faster compilation times we have
+achieved when migrating to Erlang 18.
 
-Adding the sigil letter and pressing tab then shows the available delimiters:
+## Rebar 3 support
 
-```iex
-iex(1)> ~r
-"      """    '      '''    (      /      <      [      {      |
+With Rebar 3 gaining more adoption in the Erlang community, Mix is
+now able to fetch and compile Rebar 3 dependencies. This feature is currently
+experimental and therefore opt-in: if you have a Rebar 3 dependency, you can
+ask Mix to use Rebar 3 to compile it by passing the `manager: :rebar3` option.
+Once configured, Mix will prompt you to install Rebar 3 if it is not yet
+available.
 
-```
-
-Similarly, `%<TAB>` now shows only the available structs (exceptions excluded), instead of all modules:
-
-```elixir
-iex(1)> %File.St
-File.Stat      File.Stream
-```
-
-Once you define the struct, you can hit `tab` to show all struct fields available:
-
-```elixir
-iex(1)> %URI{
-authority:    fragment:     host:         path:         port:
-query:        scheme:       userinfo:
-```
-
-As you fill a field in, the already filled fields no longer show up:
-
-```elixir
-iex(1)> %URI{path: "/example",
-authority:    fragment:     host:         port:         query:
-scheme:       userinfo:
-```
-
-Along the same lines, `SyntaxError` and `TokenMissingError` were improved to show a code snippet whenever possible:
-
-```elixir
-$ elixir -e "hello + * world"
-** (SyntaxError) nofile:1:9: syntax error before: '*'
-    |
-  1 | hello + * world
-    |         ^
-```
-
-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.
-
-## Extended code formatting
-
-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.
-
-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:
-
-```elixir
-defmodule MixMarkdownFormatter do
-  @behaviour Mix.Tasks.Format
-
-  def features(_opts) do
-    [sigils: [:M], extensions: [".md", ".markdown"]]
-  end
-
-  def format(contents, opts) do
-    # logic that formats markdown
-  end
-end
-```
-
-Now any application can use your formatter as follows:
-
-```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}"]
-]
-```
-
-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.
-
-## v1.13.0-rc.0 (2021-11-01)
+## v1.2.6 (2016-06-06)
 
 ### 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 when `nil` values are found
-  * [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`
-
-#### 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
-
-#### 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`
-
-#### Mix
-
-  * [Mix] Add `MIX_INSTALL_FORCE` environment variable support
-  * [Mix] Support `:config` and `:system_env` in `Mix.install/2`
-  * [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`
+  * [Kernel] Support Erlang 19
+  * [Kernel] Supported generated: true in the `quote` special form
 
 ### 2. Bug fixes
 
-#### EEx
+  * [Path] Fix a bug in path join with "/" followed by empty segments
+  * [String] Fix a bug in NFD normalization when followed by one-byte sized graphemes
+  * [Typespec] Correctly support `<<_::size, _::_*unit>>` syntax
 
-  * [EEx] Accept comments in EEx between do and the first clause
-  * [EEx] Accept EEx expressions where `->` is followed by newline
+## v1.2.5 (2016-04-30)
+
+### 1. Bug fixes
+
+  * [Logger] Stringify truncated function data in Logger
+  * [Logger] Ensure poorly formatted char data can also be logged by using the replacement character "�" (diamond question mark)
+  * [Mix] Do not assume `@impl` is always a list
+  * [String] Fix bugs in `String.replace_*` functions where it would not include the accumulated value for certain replacements
+
+## v1.2.4 (2016-04-01)
+
+### 1. Enhancements
+
+  * [Mix] Add `:archives` configuration to `def project` that allows projects to list archive dependencies. `--no-archives-check` (as well as `--no-deps-check`) will disable the archive check. The `:archives` option is not checked for dependencies.
+  * [Mix] Add `deps.precompile` task as hook
+  * [Mix] Support `--include-children` in `mix deps.compile` option
+  * [String] Update version of the Unicode database to 8.0.0
+
+### 2. Bug fixes
+
+  * [Application] Ensure `spec/2` returns nil for unknown applications
+  * [Integer] Fix a possible binary leak in `parse/1`
+  * [Mix] Purge Erlang modules on recompilation
+  * [String] Ensure `split/1` does not break on non-breakable whitespace
+  * [String] Ensure NFC and NFD normalization pass all of Unicode 8.0.0 tests
+  * [Version] Allow dots in build info for versions in `Version.parse/1`
+
+## v1.2.3 (2016-02-21)
+
+### 1. Enhancements
+
+  * [Base] Add `:ignore` and `:padding` option to encoding/decoding functions
+  * [Mix] Add `Mix.Projects.deps_paths` that returns the dependencies path as a map
+
+### 2. Bug fixes
+
+  * [ExUnit] Do not provide negative line numbers without generated annotation (for compatibility with Erlang 19)
+  * [Mix] Reject non fullfilled optional dependencies later on in the convergence resolution for proper dependency sorting
+  * [String] Fix incomplete data trimming on both `String.replace_trailing` and `String.rstrip`
+  * [String] Attach debug_info back into Unicode modules for Dialyzer support
+
+## v1.2.2 (2016-01-31)
+
+### 1. Enhancements
+
+  * [Kernel] Support `@compile {:autoload, false}` to disable automatic loading after compilation
+
+### 2. Bug fixes
+
+  * [ExUnit] Raise if trying to override reserved tag in `setup` blocks
+  * [Mix] Ensure retrieve compile manifests do fail if some compilers are not yet available
+  * [Mix] Automatically merge managers according to the mix > rebar3 > rebar > make order
+  * [Mix] Force recompilation if dependency was recently fetched
+
+## v1.2.1 (2016-01-14)
+
+### 1. Enhancements
+
+  * [IEx] Support remote pids/ports with IEx helper `i/1`
+  * [Protocol] Warn when `defimpl` is called for a consolidated protocol
+
+### 2. Bug fixes
+
+  * [ExUnit] Ensure `assert` macros can be used from quoted code
+  * [ExUnit] Do not warn in match assertion if variable is reused in pattern
+  * [Macro] Fix a bug in `Macro.to_string/1` where a remote function could be accidentally interpreted as a sigil
+  * [Mix] Ensure dependencies are properly skipped when `--only` option is given to `mix deps.get`
+
+## v1.2.0 (2016-01-01)
+
+### 1. Enhancements
 
 #### Elixir
 
-  * [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] 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
+  * [Application] Add `spec/1` and `spec/2` to retrieve application specification
+  * [Application] Add `get_application/1` to retrieve the application a given module belongs to
+  * [Base] Optimize encode and decode operations about 10 times
+  * [Enum] Use the faster and auto-seeding `:rand` instead of `:random` in `Enum.shuffle/1` and `Enum.random/1` and `Enum.take_random/2`
+  * [Enum] Add `Enum.with_index/2`
+  * [GenServer] Add `GenServer.stop/1` for shutting down servers reliably
+  * [IO] Add `color` related functions to `IO.ANSI`
+  * [Kernel] Support multiple aliases in `alias`, `import`, `require` and `use`. For example, `alias MyApp.{Foo, Bar, Baz}`
+  * [Kernel] Add `struct!/2`. Similar to `struct/2` but raises on invalid keys
+  * [Kernel] Warn if `@doc/@typedoc/@moduledoc` attributes are redefined
+  * [Kernel] Warn if non-variables are used in `defdelegate/2` (as they have no effect)
+  * [Kernel] Mark quoted expressions as generated, avoiding false positives on dialyzer
+  * [Kernel] Allow variables as map keys on creation `%{key => value}` and on matches `%{^key => value}`
+  * [Kernel] Allow the pin operator `^` in `fn` clauses and on the left side of `<-` in `for` comprehensions
+  * [Kernel] Introduce `with` as a special form that allows matching on right side parameters
+  * [Kernel] Warn when right hand side of `->` does not provide any expression
+  * [Kernel] Warn if the Elixir was compiled with a different endianness than the one currently available at runtime
+  * [Kernel] Warn if a variable is used after being defined exclusively in a nested context
+  * [Kernel] Warn if piping into an expression without parentheses
+  * [Macro] Add `Macro.traverse/4` that performs pre and post-walk at once
+  * [Macro] Add `Macro.camelize/1` and `Macro.underscore/1`
+  * [Process] Add `Process.get_keys/0`
+  * [Stream] Add `Stream.with_index/2`
+  * [String] Introduce `String.replace_{prefix,suffix,leading,trailing}/2`. The first two will replace only the first occurrence of the given match in string. The last two will replace all occurrences of the given match
+  * [String] Support `String.normalize/2` and `String.equivalent?/2` that perform NFD and NFC normalization
+  * [System] Add `System.time_offset`, `System.monotonic_time`, `System.system_time`, `System.convert_time_unit` and `System.unique_integer`
+  * [System] Allow `System.cmd/3` to remove variables by specifying nil values
+  * [Task] Add `Task.Supervisor.async_nolink/1/3` that spawns a supervised task without linking to the caller process
+  * [Task] Introduce `Task.yield_many/2`
+  * [Task] Raise an error when a task is queried from a non-owning process (instead of waiting forever)
 
 #### 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] Allow one test to raise multiple errors. The goal is to enable tools in the ecosystem to emit multiple failure reports from the same test
+  * [ExUnit] Support `@tag report: [:foo, :bar]` which will include the values for tags `:foo` and `:bar` whenever a test fails
 
 #### IEx
 
-  * [IEx] Fix the loss of `.iex.exs` context after a pry session
+  * [IEx] Allow `IEX_WITH_WERL` to be set on Windows to always run on WERL mode
+  * [IEx] Display type docs for `t(Module.type)` and `t(Module.type/arity)`
+  * [IEx] Add `i/1` helper that prints information about any data type
+  * [IEx] Show source code snippet whenever there is a request to pry a given process
 
 #### 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
+  * [Logger] Add file to logger metadata
 
 #### Mix
 
-  * [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 dependency is not locked
-  * [mix local.install] Do not respect `MIX_DEPS_PATH` for install commands
-  * [mix release] Improve release scripts to make sure shell errors cascade by avoiding exporting and defining variables at once
-  * [mix release] Do not boot release if RELEASE_COOKIE is empty
-  * [mix release] Allow release running as a daemon to be restarted
-  * [mix test] Allow coverage engine to also tag `case`, `cond`, and `receive` branches where the right side is a literal
-  * [Mix.Shell] Add `default` option to `Mix.Shell.yes?`
+  * [Mix] Cache and always consolidate protocols
+  * [Mix] Add `warn_test_pattern` to `mix test` that will warn on potentially misconfigured test files
+  * [Mix] Introduce `MIX_QUIET` environment variable that configures the underlying Mix task to output only error messages
+  * [Mix] Introduce `MIX_DEBUG` environment variable that prints information about the task being run
+  * [Mix] Validate git options and warn on conflicting ref, branch or tags
+  * [Mix] New umbrella applications will now share configuration and build files
+  * [Mix] Add experimental support for Rebar 3
+  * [Mix] Do not warn when an optional dependency has a conflicting `:only` option with another dependency
+  * [Mix] Raise readable error message when parsertools is not available
+  * [Mix] Add `--build` flag to `mix deps.clean DEP` to only remove artifacts from `_build`
 
-### 3. Soft-deprecations (no warnings emitted)
+### 2. Bug fixes
 
-#### Elixir
+#### Kernel
 
-  * [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`
+  * [Access] Improve error messages when using Access on non-valid key-value structures
+  * [Kernel] Raise when conflicting `:only` and `:except` are given to import
+  * [Kernel] Change `__ENV__.file` if `@file` is set for the given function
+  * [Kernel] Make `Kernel.ParallelRequire` aware of `:warning_as_errors`
+  * [Kernel] Improve error message for invalid `do`/`do:`
+  * [Macro] Ensure `Macro.to_string/2` respects operator precedence when using the access operator
+  * [Path] Do not crash when expanding paths that go beyond the root, for example, `Path.expand("/../..")`
+  * [String] Ensure `UnicodeConversionError` does not contain invalid string in its error message
+
+#### IEx
+
+  * [IEx] Do not start apps on `recompile` helper if `--no-start` was given
+  * [IEx] Avoid copying of data when evaluating every expression in IEx
 
 #### Mix
 
-  * [mix format] `Mix.Tasks.Format.formatter_opts_for_file/2` is deprecated in favor of `Mix.Tasks.Format.formatter_for_file/2`
+  * [Mix] Always run non-recursive tasks at the umbrella root
+  * [Mix] Ensure rebar projects work on directory names that contain non-latin characters
+  * [Mix] Ignore directories inside `apps` in umbrellas that do not have a `mix.exs` file
+  * [Mix] Ensure Mix can be used with path dependencies where the app name is different than the path basename
+  * [Mix] Ensure dependencies won't crash when updating from a git repository to a hex repository and the git version did not respect SemVer
+  * [Mix] Do not run remote converger if dependencies have diverged
+  * [Mix] Ensure umbrella dependencies across all environments are loaded on parent deps.get/deps.update
 
-### 4. Hard-deprecations
+#### ExUnit
 
-#### Elixir
+  * [ExUnit] Include file and line in all compilation errors for doctests
 
-  * [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
+### 3. Soft deprecations (no warnings emitted)
+
+#### Kernel
+
+  * [Dict] `Dict` and `HashDict` are soft deprecated in favor of `Map`
+  * [Keyword] `Keyword.size/1` is deprecated in favor of `length/1`
+  * [Map] `Map.size/1` is deprecated in favor of `map_size/1`
+  * [Set] `Set` and `HashSet` are soft deprecated in favor of `MapSet`
 
 #### 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
+  * [Mix] `Mix.Utils.camelize/1` and `Mix.Utils.underscore/1` are soft deprecated in favor of `Macro.camelize/1` and `Macro.underscore/1`
 
-## v1.12
+## v1.1
 
-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 v1.1 releases can be found [in the v1.1 branch](https://github.com/elixir-lang/elixir/blob/v1.1/CHANGELOG.md).

CODE_OF_CONDUCT.md

@@ -1,66 +1,22 @@
-# Code of Conduct
+# Contributor Code of Conduct
 
-Contact: elixir-lang-conduct@googlegroups.com
+As contributors and maintainers of this project, and in the interest of fostering an open and welcoming community, we pledge to respect all people who contribute through reporting issues, posting feature requests, updating documentation, submitting pull requests or patches, and other activities.
 
-## Why have a Code of Conduct?
+We are committed to making participation in this project a harassment-free experience for everyone, regardless of level of experience, gender, gender identity and expression, sexual orientation, disability, personal appearance, body size, race, ethnicity, age, religion, or nationality.
 
-As contributors and maintainers of this project, we are committed to providing a friendly, safe and welcoming environment for all, regardless of age, disability, gender, nationality, race, religion, sexuality, or similar personal characteristic.
+Examples of unacceptable behavior by participants include:
 
-The goal of the Code of Conduct is to specify a baseline standard of behavior so that people with different social values and communication styles can talk about Elixir effectively, productively, and respectfully, even in face of disagreements. The Code of Conduct also provides a mechanism for resolving conflicts in the community when they arise.
+* The use of sexualized language or imagery
+* Personal attacks
+* Trolling or insulting/derogatory comments
+* Public or private harassment
+* Publishing other's private information, such as physical or electronic addresses, without explicit permission
+* Other unethical or unprofessional conduct.
 
-## Our Values
+The Elixir Core Team has the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct. By adopting this Code of Conduct, we commit ourselves to fairly and consistently applying these principles to every aspect of managing this project. Project maintainers who do not follow or enforce the Code of Conduct may be permanently removed from the project team.
 
-These are the values Elixir developers should aspire to:
+This code of conduct applies both within project spaces and in public spaces when an individual is representing the project or its community.
 
-  * Be friendly and welcoming
-  * Be kind
-    * 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.
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by sending an e-mail to elixir-lang-conduct@googlegroups.com.
 
-The following actions are explicitly forbidden:
-
-  * Insulting, demeaning, hateful, or threatening remarks.
-  * Discrimination based on age, disability, gender, nationality, race, religion, sexuality, or similar personal characteristic.
-  * Bullying or systematic harassment.
-  * Unwelcome sexual advances.
-  * Incitement to any of these.
-
-## Where does the Code of Conduct apply?
-
-If you participate in or contribute to the Elixir ecosystem in any way, you are encouraged to follow the Code of Conduct while doing so.
-
-Explicit enforcement of the Code of Conduct applies to the official mediums operated by the Elixir project:
-
-* The [official GitHub projects][1] and code reviews.
-* The official elixir-lang mailing lists.
-* The **[#elixir][2]** IRC channel on [Libera.Chat][3].
-
-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.
-
-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.
-
-Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by emailing: elixir-lang-conduct@googlegroups.com. All complaints will be reviewed and investigated and will result in a response that is deemed necessary and appropriate to the circumstances. **All reports will be kept confidential**.
-
-**The goal of the Code of Conduct is to resolve conflicts in the most harmonious way possible**. We hope that in most cases issues may be resolved through polite discussion and mutual agreement. Bannings and other forceful measures are to be employed only as a last resort. **Do not** post about the issue publicly or try to rally sentiment against a particular individual or group.
-
-## Acknowledgements
-
-This document was based on the Code of Conduct from the Go project (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 Code of Conduct is adapted from the [Contributor Covenant](http://contributor-covenant.org), version 1.2.0, available at [http://contributor-covenant.org/version/1/2/0/](http://contributor-covenant.org/version/1/2/0/)

CONTRIBUTING.md

@@ -0,0 +1,275 @@
+# Contributing to Elixir
+
+Please take a moment to review this document in order to make the contribution
+process easy and effective for everyone involved!
+
+Also make sure you read our [Code of Conduct](CODE_OF_CONDUCT.md) that
+outlines our commitment towards an open and welcoming environment.
+
+## Using the issue tracker
+
+Use the issues tracker for:
+
+* [bug reports](#bug-reports)
+* [submitting pull requests](#pull-requests)
+
+Please **do not** use the issue tracker for personal support requests nor feature requests. Support requests should be sent to:
+
+* [the elixir-talk mailing list](https://groups.google.com/group/elixir-lang-talk)
+* [Stack Overflow](http://stackoverflow.com/questions/ask?tags=elixir)
+* **[#elixir-lang](irc://chat.freenode.net/elixir-lang)** IRC channel on [chat.freenode.net](http://www.freenode.net/)
+
+Feature requests can be discussed on [the elixir-core mailing list](https://groups.google.com/group/elixir-lang-core).
+
+We do our best to keep the issue tracker tidy and organized, making it useful
+for everyone. For example, we classify open issues per application and perceived
+difficulty of the issue, making it easier for developers to
+[contribute to Elixir](#contributing).
+
+## Bug reports
+
+A bug is a _demonstrable problem_ that is caused by the code in the repository.
+Good bug reports are extremely helpful - thank you!
+
+Guidelines for bug reports:
+
+1. **Use the GitHub issue search** — [check if the issue has already been
+   reported](https://github.com/elixir-lang/elixir/search?type=Issues).
+
+2. **Check if the issue has been fixed** — try to reproduce it using the
+   `master` branch in the repository.
+
+3. **Isolate and report the problem** — ideally create a reduced test
+   case.
+
+Please try to be as detailed as possible in your report. Include information about
+your Operating System, your Erlang and Elixir versions. Please provide steps to
+reproduce the issue as well as the outcome you were expecting! All these details
+will help developers to fix any potential bugs.
+
+Example:
+
+> Short and descriptive example bug report title
+>
+> A summary of the issue and the environment in which it occurs. If suitable,
+> include the steps required to reproduce the bug.
+>
+> 1. This is the first step
+> 2. This is the second step
+> 3. Further steps, etc.
+>
+> `<url>` - a link to the reduced test case (e.g. a GitHub Gist)
+>
+> Any other information you want to share that is relevant to the issue being
+> reported. This might include the lines of code that you have identified as
+> causing the bug, and potential solutions (and your opinions on their
+> merits).
+
+## Feature requests
+
+Feature requests are welcome and should be discussed on [the elixir-core mailing list](https://groups.google.com/group/elixir-lang-core). But take a moment to find
+out whether your idea fits with the scope and aims of the project. It's up to *you*
+to make a strong case to convince the community of the merits of this feature.
+Please provide as much detail and context as possible.
+
+## Contributing
+
+We incentivize 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` - Contains Elixir's kernel and stdlib
+
+* `eex` - Template engine that allows you to embed Elixir
+
+* `ex_unit` - Simple test framework that ships with Elixir
+
+* `iex` - IEx, Elixir's interactive shell
+
+* `mix` - Elixir's build tool
+
+You can run all tests in the root directory with `make test` and you can
+also run tests for a specific framework `make test_#{NAME}`, for example,
+`make test_ex_unit`.
+
+In case you are changing a single file, you can compile and run tests only
+for that particular file for fast development cycles. For example, if you
+are changing the String module, you can compile it and run its tests as:
+
+```sh
+bin/elixirc lib/elixir/lib/string.ex -o lib/elixir/ebin
+bin/elixir lib/elixir/test/elixir/string_test.exs
+```
+
+After your changes are done, please remember to run the full suite with
+`make test`.
+
+From time to time, your tests may fail in an existing Elixir checkout and
+may require a clean start by running `make clean compile`. You can always
+check [the official build status on Travis-CI](https://travis-ci.org/elixir-lang/elixir).
+
+With tests running and passing, you are ready to contribute to Elixir and
+send your pull requests.
+
+## Contributing Documentation
+
+Code documentation (`@doc`, `@moduledoc`, `@typedoc`) has a special convention:
+the first paragraph is considered to be a short summary.
+
+For functions, macros and callbacks say what it will do. For example write
+something like:
+
+```elixir
+@doc """
+Returns only those elements for which `fun` is `true`.
+
+...
+"""
+def filter(collection, fun) ...
+```
+
+For modules, protocols and types say what it is. For example write
+something like:
+
+```elixir
+defmodule File.Stat do
+  @moduledoc """
+  Information about a file.
+
+  ...
+  """
+
+  defstruct [...]
+end
+```
+
+Keep in mind that the first paragraph might show up in a summary somewhere, long
+texts in the first paragraph create very ugly summaries. As a rule of thumb
+anything longer than 80 characters is too long.
+
+Try to keep unnecessary details out of the first paragraph, it's only there to
+give a user a quick idea of what the documented "thing" does/is. The rest of the
+documentation string can contain the details, for example when a value and when
+`nil` is returned.
+
+If possible include examples, preferably in a form that works with doctests. For
+example:
+
+```elixir
+@doc """
+Returns only those elements for which `fun` is `true`.
+
+## Examples
+
+    iex> Enum.filter([1, 2, 3], fn(x) -> rem(x, 2) == 0 end)
+    [2]
+
+"""
+def filter(collection, fun) ...
+```
+
+This makes it easy to test the examples so that they don't go stale and examples
+are often a great help in explaining what a function does.
+
+## Pull requests
+
+Good pull requests - patches, improvements, new features - are a fantastic
+help. They should remain focused in scope and avoid containing unrelated
+commits.
+
+**NOTE**: Do not send code style changes as pull requests like changing
+the indentation of some particular code snippet or how a function is called.
+Those will not be accepted as they pollute the repository history with non
+functional changes and are often based on personal preferences.
+
+**IMPORTANT**: By submitting a patch, you agree that your work will be
+licensed under the license used by the project.
+
+If you have any large pull request in mind (e.g. implementing features,
+refactoring code, etc), **please ask first** otherwise you risk spending
+a lot of time working on something that the project's developers might
+not want to merge into the project.
+
+Please adhere to the coding conventions in the project (indentation,
+accurate comments, etc.) and don't forget to add your own tests and
+documentation. When working with Git, we recommend the following process
+in order to craft an excellent pull request:
+
+1. [Fork](https://help.github.com/fork-a-repo/) the project, clone your fork,
+  and configure the remotes:
+
+  ```sh
+  # Clone your fork of the repo into the current directory
+  git clone https://github.com/<your-username>/elixir
+  # Navigate to the newly cloned directory
+  cd elixir
+  # Assign the original repo to a remote called "upstream"
+  git remote add upstream https://github.com/elixir-lang/elixir
+  ```
+
+2. If you cloned a while ago, get the latest changes from upstream:
+
+  ```sh
+  git checkout master
+  git pull upstream master
+  ```
+
+3. Create a new topic branch (off of `master`) to contain your feature, change,
+  or fix.
+
+  **IMPORTANT**: Making changes in `master` is discouraged. You should always
+  keep your local `master` in sync with upstream `master` and make your
+  changes in topic branches.
+
+  ```sh
+  git checkout -b <topic-branch-name>
+  ```
+
+4. Commit your changes in logical chunks. Keep your commit messages organized,
+  with a short description in the first line and more detailed information on
+  the following lines. Feel free to use Git's
+  [interactive rebase](https://help.github.com/articles/interactive-rebase)
+  feature to tidy up your commits before making them public.
+
+5. Make sure all the tests are still passing.
+
+  ```sh
+  make test
+  ```
+
+  This command will compile the code in your branch and use that
+  version of Elixir to run the tests. This is needed to ensure your changes can
+  pass all the tests.
+
+6. Push your topic branch up to your fork:
+
+  ```sh
+  git push origin <topic-branch-name>
+  ```
+
+7. [Open a Pull Request](https://help.github.com/articles/using-pull-requests/)
+  with a clear title and description.
+
+8. If you haven't updated your pull request for a while, you should consider
+  rebasing on master and resolving any conflicts.
+
+  **IMPORTANT**: _Never ever_ merge upstream `master` into your branches. You
+  should always `git rebase` on `master` to bring your changes up to date when
+  necessary.
+
+  ```sh
+  git checkout master
+  git pull upstream master
+  git checkout <your-topic-branch>
+  git rebase master
+  ```
+
+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)
+
+Thank you for your contributions!

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.
-
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-
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-      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.
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-      risks associated with Your exercise of permissions under this License.
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-
-   END OF TERMS AND CONDITIONS
+  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.

Makefile

@@ -1,45 +1,40 @@
+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 $(ELIXIRC_OPTS)
+DOCS := v1.2
+CANONICAL := stable
+ELIXIRC := bin/elixirc --verbose --ignore-module-conflict
 ERLC := erlc -I lib/elixir/include
-ERL_MAKE := if [ -n "$(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
-BINDIR := bin
 INSTALL = install
 INSTALL_DIR = $(INSTALL) -m755 -d
 INSTALL_DATA = $(INSTALL) -m644
 INSTALL_PROGRAM = $(INSTALL) -m755
-GIT_REVISION = $(strip $(shell git rev-parse HEAD 2> /dev/null ))
-GIT_TAG = $(strip $(shell head="$(call GIT_REVISION)"; git tag --points-at $$head 2> /dev/null | tail -1) )
-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 publish_zips publish_docs publish_mix
 .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'; \
-		if [ $$? != 0 ]; then \
-		  echo "At least Erlang/OTP 22.0 is required to build Elixir"; \
-		  exit 1; \
-		fi
+	$(Q) erl -noshell -eval 'io:fwrite("~s", [erlang:system_info(otp_release) >= "18"])' -s erlang halt | grep -q '^true'; \
+		if [ $$? != 0 ]; then                                                                                                \
+		   echo "At least Erlang 18.0 is required to build Elixir";                                                          \
+		   exit 1;                                                                                                           \
+		fi;
 endef
 
 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 "==> $(1) (compile)"
@@ -47,65 +42,52 @@ lib/$(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;
+	@ echo "Embedding the Unicode database... (this may take a while)"
+	$(Q) cd lib/elixir && ../../$(ELIXIRC) unicode/unicode.ex -o ebin;
 
 $(eval $(call APP_TEMPLATE,ex_unit,ExUnit))
 $(eval $(call APP_TEMPLATE,logger,Logger))
@@ -116,158 +98,103 @@ $(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) $(INSTALL_DIR) "$(DESTDIR)$(PREFIX)/bin"
+	$(Q) for file in "$(DESTDIR)$(PREFIX)"/$(LIBDIR)/elixir/bin/* ; do \
+		ln -sf "../$(LIBDIR)/elixir/bin/$${file##*/}" "$(DESTDIR)$(PREFIX)/bin/" ; \
 	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}")
-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)
+SOURCE_REF = $(shell head="$$(git rev-parse HEAD)" tag="$$(git tag --points-at $$head | tail -1)" ; echo "$${tag:-$$head}\c")
+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 "v$(VERSION)" $(call LOGO_PATH) -o doc/$(2) -a http://elixir-lang.org/docs/$(CANONICAL)/$(2)/ -p http://elixir-lang.org/docs.html $(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/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 ""
+#==> Publish
 
-#==> Test tasks
+publish_zips: Precompiled.zip Docs.zip
 
-# If you modify this task, please update .cirrus.yml accordingly
-test: test_formatted test_erlang test_elixir
+publish_docs: docs
+	rm -rf ../docs/$(DOCS)/*/
+	cp -R doc/* ../docs/$(DOCS)
 
-test_windows: test test_taskkill
+#==> Tests tasks
 
-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 +204,15 @@ $(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 +222,7 @@ 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 +231,7 @@ 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 +239,24 @@ 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 $(DESTDIR)$(PREFIX)/share/man/man1
+	$(Q) $(INSTALL_DATA) man/elixir.1  $(DESTDIR)$(PREFIX)/share/man/man1
+	$(Q) $(INSTALL_DATA) man/elixirc.1 $(DESTDIR)$(PREFIX)/share/man/man1
+	$(Q) $(INSTALL_DATA) man/iex.1     $(DESTDIR)$(PREFIX)/share/man/man1
+	$(Q) $(INSTALL_DATA) man/mix.1     $(DESTDIR)$(PREFIX)/share/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 +1,15 @@
-<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/).
+[check Elixir's website](http://elixir-lang.org/).
 
-## Policies
+## Usage
 
-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.
-
-## 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:
+If you want to contribute to Elixir or run it from source, clone this
+repository to your machine, compile and test it:
 
 ```sh
 git clone https://github.com/elixir-lang/elixir.git
@@ -87,148 +21,69 @@ 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`.
 
-## Contributing
+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.
 
-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:
+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:
 
-* `elixir` - Elixir's kernel and standard library
+`Erlang/OTP 18 [erts-7.0] [source] [smp:2:2] [async-threads:10] [hipe]
+[kernel-poll:false]`
 
-* `eex` - EEx is the template engine that allows you to embed Elixir
-
-* `ex_unit` - ExUnit is a simple test framework that ships with Elixir
-
-* `iex` - IEx stands for Interactive Elixir: Elixir's interactive shell
-
-* `logger` - Logger is the built-in logger
-
-* `mix` - Mix is 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`.
-
-If you are changing just one file, you can choose to compile and run tests only
-for that particular file for fast development cycles. For example, if you
-are changing the String module, you can compile it and run its tests as:
-
-```sh
-bin/elixirc lib/elixir/lib/string.ex -o lib/elixir/ebin
-bin/elixir lib/elixir/test/elixir/string_test.exs
-```
-
-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
-`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).
-
-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)
-
-### Reviewing changes
-
-Once a pull request is sent, the Elixir team will review your changes.
-We outline our process below to clarify the roles of everyone involved.
-
-All pull requests must be approved by two committers before being merged into
-the repository. 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 Elixir team may optionally assign someone to review a pull request.
-If 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.
+If you have the correct version and tests still fail, feel free to
+[open an issue][2].
 
 ## Building documentation
 
-Building the documentation requires [ExDoc](https://github.com/elixir-lang/ex_doc)
-to be installed and built alongside Elixir:
+Building the documentation requires
+[ExDoc](https://github.com/elixir-lang/ex_doc) to be installed and built
+alongside Elixir.
 
 ```sh
 # After cloning and compiling Elixir, in its parent directory:
 git clone git://github.com/elixir-lang/ex_doc.git
 cd ex_doc && ../elixir/bin/mix do deps.get, compile
+cd ../elixir && make docs
 ```
 
-Now go back to Elixir's root directory and run:
+This will produce documentation sets for `elixir`, `mix`, etc., under the `doc` directory.
 
-```sh
-make docs                  # to generate HTML pages
-make docs DOCS_FORMAT=epub # to generate EPUB documents
-```
+## Contributing
 
-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).
+We appreciate any contribution to Elixir.
+Check our [CODE_OF_CONDUCT.md](CODE_OF_CONDUCT.md) and
+[CONTRIBUTING.md](CONTRIBUTING.md) guides for more information.
+We usually keep a list of features and bugs [in the issue tracker][2].
 
-## Development links
+## Important links
 
-  * [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
+* [Elixir Website][1]
+* [Elixir Documentation][7]
+* **[#elixir-lang][5]** on [Freenode][6] IRC
+* [Issue tracker][2]
+* [elixir-talk Mailing list (questions)][3]
+* [elixir-core Mailing list (development)][4]
 
-  [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
+  [3]: https://groups.google.com/group/elixir-lang-talk
+  [4]: https://groups.google.com/group/elixir-lang-core
+  [5]: https://webchat.freenode.net/?channels=#elixir-lang
+  [6]: http://www.freenode.net
+  [7]: http://elixir-lang.org/docs.html
 
 ## 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 +1,41 @@
 # 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. Publish new docs with `make publish_docs`, copy docs to `docs/stable` if appropriate, and push to GitHub Pages
 
-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 publish_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` file 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. Build and push standalone Mix with `make publish_mix` (requires AWS credentials)
 
-## Creating a new vMAJOR.MINOR branch
+## New vMAJOR.MINOR releases
 
-### In the new branch
+12. Create a new branch "vMAJOR.MINOR"
 
-1. Set `CANONICAL=` in /Makefile
+13. Move docs generation to `docs/vMAJOR.MINOR` in Makefile and copy them from `docs/stable` (change index.html accordingly)
 
-2. Update tables in /SECURITY.md and "Compatibility and Deprecations"
+14. In master, bump versions, start new CHANGELOG, add `-dev` back and commit "Start vVERSION+1"
 
-3. Commit "Branch out vMAJOR.MINOR"
+## Places where version is mentioned
 
-### Back in master
-
-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"
+* VERSION (make sure there is no newline in this file)
+* CHANGELOG.md
+* src/elixir.app.src (not lib/elixir/src/elixir.app.src)

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 @@
-1.13.0-rc.0
+1.2.6

bin/elixir

@@ -1,62 +1,27 @@
 #!/bin/sh
-set -e
+if [ $# -eq 0 ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
+  echo "Usage: `basename $0` [options] [.exs file] [data]
 
-ELIXIR_VERSION=1.13.0-rc.0
+  -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
+  -pr \"file\"        Requires the given files/patterns in parallel (*)
+  -pa \"path\"        Prepends the given path to Erlang code path (*)
+  -pz \"path\"        Appends the given path to Erlang code path (*)
+  --app \"app\"       Start the given app and its dependencies (*)
+  --erl \"switches\"  Switches to be passed down to Erlang (*)
+  --name \"name\"     Makes and assigns a name to the distributed node
+  --sname \"name\"    Makes and assigns a short name to the distributed node
+  --cookie \"cookie\" Sets a cookie for this distributed node
+  --hidden          Makes a hidden node
+  --detached        Starts the Erlang VM detached from console
+  --werl            Uses Erlang's Windows shell GUI (Windows only)
+  --no-halt         Does not halt the Erlang VM after execution
 
-if [ $# -eq 0 ] || { [ $# -eq 1 ] && { [ "$1" = "--help" ] || [ "$1" = "-h" ]; }; }; then
-  cat <<USAGE >&2
-Usage: $(basename "$0") [options] [.exs file] [data]
-
-## 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
-
-  --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 +31,56 @@ 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" "$3"
-        ;;
-    --detached)
-        echo "warning: the --detached option is deprecated" >&2
-        ERL="$ERL -detached"
-        ;;
-    --hidden)
-        ERL="$ERL -hidden"
-        ;;
-    --logger-otp-reports)
-        S=2
-        if [ "$2" = 'true' ] || [ "$2" = 'false' ]; then
-          ERL="$ERL -logger handle_otp_reports $2"
-        fi
-        ;;
-    --logger-sasl-reports)
-        S=2
-        if [ "$2" = 'true' ] || [ "$2" = 'false' ]; then
-          ERL="$ERL -logger handle_sasl_reports $2"
-        fi
-        ;;
-    --erl)
-        S=2
-        ERL="$ERL $2"
+    --detached|--hidden)
+        ERL="$ERL `echo $PEEK | cut -c 2-`"
         ;;
     --cookie)
-        S=2
-        erl_set "-setcookie"
-        erl_set "$2"
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        ERL="$ERL -setcookie "$VAL""
         ;;
     --sname|--name)
-        S=2
-        erl_set "$(echo "$1" | cut -c 2-)"
-        erl_set "$2"
+        I=$(expr $I + 1)
+        eval "VAL=\${$I}"
+        ERL="$ERL `echo $PEEK | cut -c 2-` "$VAL""
         ;;
-    --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 "$RUN_ERL_LOG" "-")" ]; then
-          echo "--pipe-to : LOGDIR cannot be a switch" >&2 && exit 1
-        fi
+    --erl)
+        I=$(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 "$0")
@@ -215,30 +89,21 @@ SCRIPT_PATH=$(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 +1,106 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-
-set ELIXIR_VERSION=1.13.0-rc.0
-
-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
+@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
+setlocal
+if ""%1""==""""       goto :documentation
+if ""%1""==""--help"" goto :documentation
+if ""%1""==""-h""     goto :documentation
+if ""%1""==""/h""     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
+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   --app app         Start the given app and its dependencies (*)
+echo   --erl switches    Switches to be passed down to erlang (*)
+echo   --name name       Makes and assigns a name to the distributed node
+echo   --sname name      Makes and assigns a short name to the distributed node
+echo   --cookie cookie   Sets a cookie for this distributed node
+echo   --hidden          Makes a hidden node
+echo   --detached        Starts the Erlang VM detached from console
+echo   --werl            Uses Erlang's Windows shell GUI
+echo   --no-halt         Does not halt the Erlang VM after execution
 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
-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
-  goto expand_erl_libs
-)
+set par="%1"
 shift
-set par="!par:"=\"!"
-if !endLoop! == 1 (
-  set parsElixir=!parsElixir! !par!
-  goto startloop
+if "%par%"=="" (
+  rem if no parameters defined
+  goto :expand_erl_libs
+)
+if "%par%"=="""" (
+  rem if no parameters defined - special case for parameter that is already quoted
+  goto :expand_erl_libs
 )
 rem ******* EXECUTION OPTIONS **********************
-if !par!=="--werl"   (set useWerl=1 && 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
-)
-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)
+IF "%par%"==""--werl"" (Set useWerl=1)
+IF "%par%"==""+iex"" (Set runMode="iex")
+rem ******* elixir parameters **********************
+rem Note: we don't have to do anything with options that don't take an argument
+IF """"=="%par:-e=%"      (shift) 
+IF """"=="%par:-r=%"      (shift) 
+IF """"=="%par:-pr=%"     (shift) 
+IF """"=="%par:-pa=%"     (shift) 
+IF """"=="%par:-pz=%"     (shift) 
+IF """"=="%par:--app=%"   (shift) 
+IF """"=="%par:--remsh=%" (shift) 
 rem ******* ERLANG PARAMETERS **********************
-if ""==!par:--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:--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!
-) else (
-  "!ERTS_BIN!erl.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 (
+  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
+  -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
+  --ignore-module-conflict
+  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+  --verbose        Print informational messages.
 
-  --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

@@ -1,12 +1,10 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-setlocal
+@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
 set argc=0
 for %%A in (%*) do (
-  if /I "%%A"=="--help" goto documentation
-  if /I "%%A"=="-h"     goto documentation
-  if /I "%%A"=="/h"     goto documentation
-  if    "%%A"=="/?"     goto documentation
-  set /A argc+=1
+    if "%%A"=="--help" goto documentation
+    if "%%A"=="-h"     goto documentation
+    if "%%A"=="/h"     goto documentation
+    set /A argc+=1
 )
 if %argc%==0 goto documentation
 goto run
@@ -14,24 +12,15 @@ 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
-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  --ignore-module-conflict
+echo  --warnings-as-errors Treat warnings as errors and return non-zero exit code
+echo  --verbose        Print informational messages.
 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
-echo ** Options can be passed to the Erlang compiler using ERL_COMPILER_OPTIONS
-goto end
-
+echo ** Options can be passed to the Erlang compiler using ERL_COMPILER_OPTIONS >&2
 :run
 call "%~dp0\elixir.bat" +elixirc %*
-
-:end
-endlocal

bin/iex

@@ -1,18 +1,29 @@
 #!/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
+  -e \"command\"      Evaluates the given command (*)
+  -r \"file\"         Requires the given files/patterns (*)
+  -S \"script\"       Finds and executes the given script
+  -pr \"file\"        Requires the given files/patterns in parallel (*)
+  -pa \"path\"        Prepends the given path to Erlang code path (*)
+  -pz \"path\"        Appends the given path to Erlang code path (*)
+  --app \"app\"       Start the given app and its dependencies (*)
+  --erl \"switches\"  Switches to be passed down to Erlang (*)
+  --name \"name\"     Makes and assigns a name to the distributed node
+  --sname \"name\"    Makes and assigns a short name to the distributed node
+  --cookie \"cookie\" Sets a cookie for this distributed node
+  --hidden          Makes a hidden node
+  --werl            Uses Erlang's Windows shell GUI (Windows only)
+  --detached        Starts the Erlang VM detached from console
+  --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
 
-The following options are exclusive to IEx:
-
-  --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 +33,10 @@ 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

@@ -1,27 +1,4 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-setlocal
-if /I ""%1""==""--help"" goto documentation
-if /I ""%1""==""-h""     goto documentation
-if /I ""%1""==""/h""     goto documentation
-if    ""%1""==""/?""     goto documentation
-goto run
-
-:documentation
-echo Usage: %~nx0 [options] [.exs file] [data]
-echo.
-echo The following options are exclusive to IEx:
-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.
-echo Set the IEX_WITH_WERL environment variable to always use werl.
-echo It accepts all other options listed by "elixir --help".
-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% %*
-:end
-endlocal
+@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
+@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% %*
+@set __ELIXIR_IEX_FLAGS=

bin/mix

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

bin/mix.bat

@@ -1,2 +1,2 @@
-@if defined ELIXIR_CLI_ECHO (@echo on) else (@echo off)
-call "%~dp0\elixir.bat" "%~dp0\mix" %*
+@if defined ELIXIR_CLI_ECHO (@echo on) else  (@echo off)
+call "%~dp0\elixir.bat" "%~dp0\mix" %*

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
 
@@ -12,46 +11,37 @@ 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.
 
   ## Options
 
-  All functions in this module accept EEx-related options.
+  All functions in this module accepts 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).
 
   ## Engine
 
@@ -83,13 +73,7 @@ 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
@@ -98,45 +82,42 @@ 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:
 
       <%= {:ok, v} = Access.fetch(assigns, :foo); v %>
 
-  The `assigns` extension is useful when the number of variables
+  The assigns extension is useful when the number of variables
   required by the template is not specified at compilation time.
   """
 
   @doc """
-  Generates a function definition from the 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
-    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)
+  defmacro function_from_string(kind, name, source, args \\ [], options \\ []) do
+    quote bind_quoted: binding do
+      info = Keyword.merge [file: __ENV__.file, line: __ENV__.line], options
+      args = Enum.map args, fn arg -> {arg, [line: info[:line]], nil} end
+      compiled = EEx.compile_string(source, info)
 
       case kind do
-        :def -> def unquote(name)(unquote_splicing(args)), do: unquote(compiled)
-        :defp -> defp unquote(name)(unquote_splicing(args)), do: unquote(compiled)
+        :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 +125,8 @@ 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 +139,42 @@ 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)
+    quote bind_quoted: binding do
+      info = Keyword.merge options, [file: file, line: 1]
+      args = Enum.map args, fn arg -> {arg, [line: 1], nil} end
       compiled = EEx.compile_file(file, info)
 
       @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()
-  def compile_string(source, options \\ []) when is_binary(source) and is_list(options) do
+  def compile_string(source, options \\ []) do
     EEx.Compiler.compile(source, options)
   end
 
   @doc """
-  Gets a `filename` and 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)
+  def compile_file(filename, options \\ []) do
+    options = Keyword.merge options, [file: filename, line: 1]
     compile_string(File.read!(filename), options)
   end
 
@@ -247,13 +183,11 @@ 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()
-  def eval_string(source, bindings \\ [], options \\ [])
-      when is_binary(source) and is_list(bindings) and is_list(options) do
+  def eval_string(source, bindings \\ [], options \\ []) do
     compiled = compile_string(source, options)
     do_eval(compiled, bindings, options)
   end
@@ -266,16 +200,12 @@ 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()
-  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)
+  def eval_file(filename, bindings \\ [], 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 +9,64 @@ 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()
-  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
+  def compile(source, opts) do
+    file   = opts[:file] || "nofile"
+    line   = opts[:line] || 1
+    trim   = opts[:trim] || false
+    case EEx.Tokenizer.tokenize(source, line, trim: trim) do
       {:ok, tokens} ->
-        state = %{
-          engine: opts[:engine] || @default_engine,
-          file: file,
-          line: line,
-          quoted: [],
-          start_line: nil,
-          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)
+      {: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.
+  # Generates the buffers by handling each expression from the tokenizer
 
-  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
@@ -186,29 +74,23 @@ defmodule EEx.Compiler do
   defp wrap_expr(current, line, buffer, chars, state) do
     new_lines = List.duplicate(?\n, line - state.line)
     key = length(state.quoted)
-    placeholder = '__EEX__(' ++ Integer.to_charlist(key) ++ ');'
-    count = current ++ placeholder ++ new_lines ++ chars
-    new_state = %{state | quoted: [{key, state.engine.handle_end(buffer)} | state.quoted]}
-
-    {count, new_state}
+    placeholder = '__EEX__(' ++ Integer.to_char_list(key) ++ ');'
+    {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}
-  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 +100,7 @@ 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 +113,10 @@ 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

@@ -2,102 +2,51 @@ 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 three functions:
 
-  This module also ships with a default engine implementation
-  you can delegate to. See `EEx.SmartEngine` as an example.
+    * `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 handle_body(Macro.t) :: Macro.t
+  @callback handle_text(Macro.t, String.t) :: Macro.t
+  @callback handle_expr(Macro.t, String.t, Macro.t) :: Macro.t
 
   @doc false
-  @deprecated "Use explicit delegation to EEx.Engine instead"
   defmacro __using__(_) do
     quote do
       @behaviour EEx.Engine
 
-      def init(opts) do
-        EEx.Engine.init(opts)
+      def handle_body(body) do
+        EEx.Engine.handle_body(body)
       end
 
-      def handle_body(state) do
-        EEx.Engine.handle_body(state)
+      def handle_text(buffer, text) do
+        EEx.Engine.handle_text(buffer, text)
       end
 
-      def handle_begin(state) do
-        EEx.Engine.handle_begin(state)
+      def handle_expr(buffer, marker, expr) do
+        EEx.Engine.handle_expr(buffer, marker, expr)
       end
 
-      def handle_end(state) do
-        EEx.Engine.handle_end(state)
-      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]
     end
   end
 
@@ -110,112 +59,71 @@ 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()
   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 1.3 or 1.4
   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.write :stderr, "warning: assign @#{key} not available in eex template. " <>
+                          "Please ensure all assigns are given as options. " <>
+                          "Available assigns: #{inspect keys}\n" <>
+                          Exception.format_stacktrace
         nil
     end
   end
 
-  @doc "Default implementation for `c:init/1`."
-  def init(_opts) do
-    %{
-      binary: [],
-      dynamic: [],
-      vars_count: 0
-    }
+  @doc """
+  The default implementation simply returns the given expression.
+  """
+  def handle_body(quoted) do
+    quoted
   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 concatenates text to the buffer.
+  """
+  def handle_text(buffer, text) do
+    quote do: unquote(buffer) <> unquote(text)
   end
 
-  @doc "Default implementation for `c:handle_end/1`."
-  def handle_end(quoted) do
-    handle_body(quoted)
+  @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.
+  """
+  @spec handle_expr(Macro.t, String.t, Macro.t) :: Macro.t
+  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_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)}
-  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 +1,72 @@
 defmodule EEx.Tokenizer do
   @moduledoc false
 
-  @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]
-
   @doc """
-  Tokenizes the given charlist or binary.
+  Tokenizes the given char list 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, contents}`
+    * `{:expr, line, marker, contents}`
+    * `{:start_expr, line, marker, contents}`
+    * `{:middle_expr, line, marker, contents}`
+    * `{:end_expr, line, marker, contents}`
 
-  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()}
+  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) do
+    tokenize(String.to_char_list(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) 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 +75,141 @@ 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 +1,36 @@
-Code.require_file("../test_helper.exs", __DIR__)
+Code.require_file "../test_helper.exs", __DIR__
 
 defmodule EEx.SmartEngineTest do
   use ExUnit.Case, async: true
 
   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})
-  end
-
-  test "error with missing assigns" do
-    stderr =
-      ExUnit.CaptureIO.capture_io(:stderr, fn ->
-        assert_eval("", "<%= @foo %>", assigns: %{})
-      end)
-
-    assert stderr =~ "assign @foo not available in EEx template"
+    assert_eval "1", "<%= @foo %>", assigns: %{foo: 1}
   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 +156,7 @@ 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 '%>'"}
   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/Emakefile

@@ -1,16 +0,0 @@
-{'src/*', [
-  warn_unused_vars,
-  warn_export_all,
-  warn_shadow_vars,
-  warn_unused_import,
-  warn_unused_function,
-  warn_bif_clash,
-  warn_unused_record,
-  warn_deprecated_function,
-  warn_obsolete_guard,
-  warn_exported_vars,
-  %% warn_missing_spec,
-  %% warn_untyped_record,
-  debug_info,
-  {outdir, "ebin/"}
-]}.

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 +1,20 @@
 defmodule Access do
   @moduledoc """
-  Key-based access to data structures.
+  Key-based access to data structures via the `foo[bar]` 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:
+  ## Key-based 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]
@@ -23,212 +24,118 @@ defmodule Access do
       iex> star_ratings[1.5]
       "★☆"
 
+  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 to key-value
+  data structures. The implementation should be added to the
+  module that defines the struct being access. Access requires the
+  key comparison to be implemented using the `===` operator.
 
-      iex> nil[:a]
-      nil
+  ## Field-based 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. That's by design, as Access is meant to be used for
+  dynamic key-value structures, like maps and keywords, and not
+  by static ones like structs.
 
-      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
-      iex> put_in(users["john"][:age], 28)
-      %{"john" => %{age: 28}, "meg" => %{age: 23}}
+  However Elixir already provides a field-based lookup for structs.
+  Imagine a struct named `User` with name and age fields. 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:
 
-  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` cannot be extended by
+  the developers, and will be always restricted to only maps and
+  structs.
 
-  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:
+  Summing up:
 
-      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}
-        ]
-      }
+    * `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
 
-  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
   @type key :: any
   @type value :: any
 
-  @type get_fun(data) ::
-          (:get, data, (term -> term) -> new_data :: container)
+  @callback fetch(t, key) :: {:ok, value} | :error
+  @callback get_and_update(t, key, (value -> {value, value})) :: {value, t}
 
-  @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.
-
-  Many of the functions defined in the `Access` module internally call this
-  function. This function is also used when the square-brackets access syntax
-  (`structure[key]`) is used: the `fetch/2` callback implemented by the module
-  that defines the `structure` struct is invoked and if it returns `{:ok,
-  value}` then `value` is returned, or if it returns `:error` then `nil` is
-  returned.
-
-  See the `Map.fetch/2` and `Keyword.fetch/2` implementations for examples of
-  how to implement this callback.
-  """
-  @callback fetch(term :: t, key) :: {:ok, value} | :error
-
-  @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`.
-
-  If the passed function returns `{current_value, new_value}`,
-  the return value of this callback should be `{current_value, new_data}`, where:
-
-    * `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`.
-
-  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
-
-  @doc """
-  Invoked to "pop" the value under `key` out of the given data structure.
-
-  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 `key` is not present in the given structure, a tuple `{value, data}`
-  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
-
-  defmacrop raise_undefined_behaviour(exception, module, top) do
+  defmacrop raise_undefined_behaviour(e, struct, top) do
     quote do
-      exception =
-        case __STACKTRACE__ do
-          [unquote(top) | _] ->
-            reason = "#{inspect(unquote(module))} does not implement the Access behaviour"
-            %{unquote(exception) | reason: reason}
-
+      stacktrace = System.stacktrace
+      e =
+        case stacktrace do
+          [unquote(top)|_] ->
+            %{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
-
+  Fetches the container's value for the given key.
   """
-  @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
+  def fetch(%{} = map, key) do
+    :maps.find(key, map)
   end
 
   def fetch(list, key) when is_list(list) and is_atom(key) do
     case :lists.keyfind(key, 1, list) do
-      {_, value} -> {:ok, value}
+      {^key, value} -> {:ok, value}
       false -> :error
     end
   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
@@ -236,125 +143,45 @@ defmodule Access do
   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"
-
+  Gets the container's value for the given key.
   """
-  @doc since: "1.10.0"
-  @spec fetch!(container, term) :: term
-  def fetch!(container, key) do
+  @spec get(t, term, term) :: term
+  def get(container, key, default \\ nil) 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
       {: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 container's value for the given key, in a single pass.
 
-  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.
-
-  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]}
+  The argument function `fun` must receive the value for the given `key` (or
+  `nil` if the key doesn't exist in `container`). It must return a tuple
+  containing the `get` value and the new value to be stored in the `container`.
 
+  This function returns a two-element tuple.
+  The first element is the `get` value, as returned by `fun`.
+  The second element is the container, updated with the value returned by `fun`.
   """
-  @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(t, term, (term -> {get, term})) :: {get, t} when get: var
   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
-    Map.get_and_update(map, key, fun)
+  def get_and_update(%{} = map, key, fun) do
+    current_value = case :maps.find(key, map) do
+      {:ok, value} -> value
+      :error -> nil
+    end
+
+    {get, update} = fun.(current_value)
+    {get, :maps.put(key, update, map)}
   end
 
   def get_and_update(list, key, fun) when is_list(list) do
@@ -362,468 +189,7 @@ 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"
-  end
-
-  @doc """
-  Removes the entry with a given key from a container (a map, keyword
-  list, or struct that implements the `Access` behaviour).
-
-  Returns a tuple containing the value associated with the key and the
-  updated container. `nil` is returned for the value if the key isn't
-  in the container.
-
-  ## Examples
-
-  With a map:
-
-      iex> Access.pop(%{name: "Elixir", creator: "Valim"}, :name)
-      {"Elixir", %{creator: "Valim"}}
-
-  A keyword list:
-
-      iex> Access.pop([name: "Elixir", creator: "Valim"], :name)
-      {"Elixir", [creator: "Valim"]}
-
-  An unknown key:
-
-      iex> Access.pop(%{name: "Elixir", creator: "Valim"}, :year)
-      {nil, %{creator: "Valim", name: "Elixir"}}
-
-  """
-  @spec pop(data, key) :: {value, data} when data: container
-  def pop(%module{} = container, key) do
-    module.pop(container, key)
-  rescue
-    exception in UndefinedFunctionError ->
-      raise_undefined_behaviour(exception, module, {^module, :pop, [^container, ^key], _})
-  end
-
-  def pop(map, key) when is_map(map) do
-    Map.pop(map, key)
-  end
-
-  def pop(list, key) when is_list(list) do
-    Keyword.pop(list, key)
-  end
-
-  def pop(nil, key) do
-    raise ArgumentError, "could not pop key #{inspect(key)} on a nil value"
-  end
-
-  ## Accessors
-
-  @doc """
-  Returns a function that accesses the given key in a map/struct.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  The returned function uses the default value if the key does not exist.
-  This can be used to specify defaults and safely traverse missing keys:
-
-      iex> get_in(%{}, [Access.key(:user, %{}), Access.key(:name, "meg")])
-      "meg"
-
-  Such is also useful when using update functions, allowing us to introduce
-  values as we traverse the data structure for updates:
-
-      iex> put_in(%{}, [Access.key(:user, %{}), Access.key(:name)], "Mary")
-      %{user: %{name: "Mary"}}
-
-  ## Examples
-
-      iex> map = %{user: %{name: "john"}}
-      iex> get_in(map, [Access.key(:unknown, %{}), Access.key(:name, "john")])
-      "john"
-      iex> get_and_update_in(map, [Access.key(:user), Access.key(:name)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: %{name: "JOHN"}}}
-      iex> pop_in(map, [Access.key(:user), Access.key(:name)])
-      {"john", %{user: %{}}}
-
-  An error is raised if the accessed structure is not a map or a struct:
-
-      iex> get_in([], [Access.key(:foo)])
-      ** (BadMapError) expected a map, got: []
-
-  """
-  @spec key(key, term) :: access_fun(data :: struct | map, current_value :: term)
-  def key(key, default \\ nil) do
-    fn
-      :get, data, next ->
-        next.(Map.get(data, key, default))
-
-      :get_and_update, data, next ->
-        value = Map.get(data, key, default)
-
-        case next.(value) do
-          {get, update} -> {get, Map.put(data, key, update)}
-          :pop -> {value, Map.delete(data, key)}
-        end
-    end
-  end
-
-  @doc """
-  Returns a function that accesses the given key in a map/struct.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  Similar to `key/2`, but the returned function raises if the key does not exist.
-
-  ## Examples
-
-      iex> map = %{user: %{name: "john"}}
-      iex> get_in(map, [Access.key!(:user), Access.key!(:name)])
-      "john"
-      iex> get_and_update_in(map, [Access.key!(:user), Access.key!(:name)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: %{name: "JOHN"}}}
-      iex> pop_in(map, [Access.key!(:user), Access.key!(:name)])
-      {"john", %{user: %{}}}
-      iex> get_in(map, [Access.key!(:user), Access.key!(:unknown)])
-      ** (KeyError) key :unknown not found in: %{name: \"john\"}
-
-  An error is raised if the accessed structure is not a map/struct:
-
-      iex> get_in([], [Access.key!(:foo)])
-      ** (RuntimeError) Access.key!/1 expected a map/struct, got: []
-
-  """
-  @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)}"
-    end
-  end
-
-  @doc ~S"""
-  Returns a function that accesses the element at the given index in a tuple.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  The returned function raises if `index` is out of bounds.
-
-  Note that popping elements out of tuples is not possible and raises an
-  error.
-
-  ## Examples
-
-      iex> map = %{user: {"john", 27}}
-      iex> get_in(map, [:user, Access.elem(0)])
-      "john"
-      iex> get_and_update_in(map, [:user, Access.elem(0)], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {"john", %{user: {"JOHN", 27}}}
-      iex> pop_in(map, [:user, Access.elem(0)])
-      ** (RuntimeError) cannot pop data from a tuple
-
-  An error is raised if the accessed structure is not a tuple:
-
-      iex> get_in(%{}, [Access.elem(0)])
-      ** (RuntimeError) Access.elem/1 expected a tuple, got: %{}
-
-  """
-  @spec elem(non_neg_integer) :: access_fun(data :: tuple, current_value :: term)
-  def elem(index) when is_integer(index) and index >= 0 do
-    pos = index + 1
-
-    fn
-      :get, data, next when is_tuple(data) ->
-        next.(:erlang.element(pos, data))
-
-      :get_and_update, data, next when is_tuple(data) ->
-        value = :erlang.element(pos, data)
-
-        case next.(value) do
-          {get, update} -> {get, :erlang.setelement(pos, data, update)}
-          :pop -> raise "cannot pop data from a tuple"
-        end
-
-      _op, data, _next ->
-        raise "Access.elem/1 expected a tuple, got: #{inspect(data)}"
-    end
-  end
-
-  @doc ~S"""
-  Returns a function that accesses all the elements in a list.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  ## Examples
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.all(), :name])
-      ["john", "mary"]
-      iex> get_and_update_in(list, [Access.all(), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {["john", "mary"], [%{name: "JOHN"}, %{name: "MARY"}]}
-      iex> pop_in(list, [Access.all(), :name])
-      {["john", "mary"], [%{}, %{}]}
-
-  Here is an example that traverses the list dropping even
-  numbers and multiplying odd numbers by 2:
-
-      iex> require Integer
-      iex> get_and_update_in([1, 2, 3, 4, 5], [Access.all()], fn num ->
-      ...>   if Integer.is_even(num), do: :pop, else: {num, num * 2}
-      ...> end)
-      {[1, 2, 3, 4, 5], [2, 6, 10]}
-
-  An error is raised if the accessed structure is not a list:
-
-      iex> get_in(%{}, [Access.all()])
-      ** (RuntimeError) Access.all/0 expected a list, got: %{}
-
-  """
-  @spec all() :: access_fun(data :: list, current_value :: list)
-  def all() do
-    &all/3
-  end
-
-  defp all(:get, data, next) when is_list(data) do
-    Enum.map(data, next)
-  end
-
-  defp all(:get_and_update, data, next) when is_list(data) do
-    all(data, next, _gets = [], _updates = [])
-  end
-
-  defp all(_op, data, _next) do
-    raise "Access.all/0 expected a list, got: #{inspect(data)}"
-  end
-
-  defp all([head | rest], next, gets, updates) do
-    case next.(head) do
-      {get, update} -> all(rest, next, [get | gets], [update | updates])
-      :pop -> all(rest, next, [head | gets], updates)
-    end
-  end
-
-  defp all([], _next, gets, updates) do
-    {:lists.reverse(gets), :lists.reverse(updates)}
-  end
-
-  @doc ~S"""
-  Returns a function that accesses the element at `index` (zero based) of a list.
-
-  The returned function is typically passed as an accessor to `Kernel.get_in/2`,
-  `Kernel.get_and_update_in/3`, and friends.
-
-  ## Examples
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.at(1), :name])
-      "mary"
-      iex> get_in(list, [Access.at(-1), :name])
-      "mary"
-      iex> get_and_update_in(list, [Access.at(0), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {"john", [%{name: "JOHN"}, %{name: "mary"}]}
-      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:
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> pop_in(list, [Access.at(0)])
-      {%{name: "john"}, [%{name: "mary"}]}
-      iex> pop_in(list, [Access.at(0), :name])
-      {"john", [%{}, %{name: "mary"}]}
-
-  When the index is out of bounds, `nil` is returned and the update function is never called:
-
-      iex> list = [%{name: "john"}, %{name: "mary"}]
-      iex> get_in(list, [Access.at(10), :name])
-      nil
-      iex> get_and_update_in(list, [Access.at(10), :name], fn prev ->
-      ...>   {prev, String.upcase(prev)}
-      ...> end)
-      {nil, [%{name: "john"}, %{name: "mary"}]}
-
-  An error is raised 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
-  end
-
-  defp at(:get, data, index, next) when is_list(data) do
-    data |> Enum.at(index) |> next.()
-  end
-
-  defp at(:get_and_update, data, index, next) when is_list(data) do
-    get_and_update_at(data, index, next, [], fn -> nil end)
-  end
-
-  defp at(_op, data, _index, _next) do
-    raise "Access.at/1 expected a list, got: #{inspect(data)}"
-  end
-
-  defp get_and_update_at([head | rest], 0, next, updates, _default_fun) 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
-  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)}
+    raise ArgumentError,
+      "could not put/update key #{inspect key} on a nil value"
   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`.
@@ -249,36 +144,26 @@ defmodule Agent do
   ## Return values
 
   If the server is successfully created and initialized, the function returns
-  `{:ok, pid}`, where `pid` is the PID of the server. If an agent with the
+  `{:ok, pid}`, where `pid` is the pid of the server. If an agent with the
   specified name already exists, the function returns
-  `{:error, {:already_started, pid}}` with the PID of that process.
-
-  If the given function callback fails, 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"}
+  `{:error, {:already_started, pid}}` with the pid of that process.
 
+  If the given function callback fails with `reason`, the function returns
+  `{:error, reason}`.
   """
-  @spec start_link((() -> term), GenServer.options()) :: on_start
+  @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 +295,25 @@ 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)
+    if is_integer(reason) or reason == :infinity do
+      IO.write :stderr, "warning: Agent.stop(agent, timeout) is deprecated, " <>
+                        "please use Agent.stop(agent, :normal, timeout) instead\n" <>
+                        Exception.format_stacktrace
+      :gen.stop(agent, :normal, reason)
+    else
+      :gen.stop(agent, reason, timeout)
+    end
   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/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 """
@@ -54,29 +16,24 @@ 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
 
   @doc """
-  Converts an atom to a charlist.
+  Converts an atom to a char list.
 
   Inlined by the compiler.
 
   ## Examples
 
-      iex> Atom.to_charlist(:"An atom")
+      iex> Atom.to_char_list(:"An atom")
       'An atom'
 
   """
-  @spec to_charlist(atom) :: charlist
-  def to_charlist(atom) do
+  @spec to_char_list(atom) :: char_list
+  def to_char_list(atom) do
     :erlang.atom_to_list(atom)
   end
-
-  @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 `MyModule.__behaviour__(:callbacks)`,
-  `MyModule.behaviour_info(:callbacks)` can be used.
+  Instead of `defcallback`, one can simply use `@callback`.
+  Instead of `defmacrocallback`, one can simply use `@macrocallback`.
+  Instead of `__behaviour__(:callbacks)`, one can simply use `behaviour_info(:callbacks)`.
   """
 
-  @moduledoc deprecated: "Use @callback and @macrocallback attributes instead"
+  # TODO: Deprecate by 1.2
+  # TODO: Remove by 2.0
 
   @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
 
@@ -90,33 +80,20 @@ defmodule Behaviour do
   @doc false
   defmacro __using__(_) do
     quote do
-      warning =
-        "the Behaviour module is deprecated. Instead of using this module, " <>
-          "use the @callback and @macrocallback module attributes. See the " <>
-          "documentation for Module for more information on these attributes"
-
-      IO.warn(warning)
-
       @doc false
       def __behaviour__(:callbacks) do
         __MODULE__.behaviour_info(:callbacks)
       end
 
       def __behaviour__(:docs) do
-        {: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

@@ -1,59 +1,44 @@
 defmodule Bitwise do
   @moduledoc """
-  A set of functions that perform calculations on bits.
+  This module provides macro-based operators that perform calculations
+  on (sets of) bits.
 
-  All bitwise functions work only on integers; otherwise an
-  `ArithmeticError` is raised.
-
-  The functions in this module come in two flavors: named or
-  operators. For example:
+  In general, you should `use` the Bitwise module as a whole:
 
       iex> use Bitwise
-      iex> bnot(1) # named
+      iex> bnot 1
       -2
-      iex> 1 &&& 1 # operator
+      iex> 1 &&& 1
       1
 
-  If you prefer to use only operators or skip them, you can
-  pass the following options:
+  When used, it accepts the following options:
 
-    * `:only_operators` - includes only operators
-    * `:skip_operators` - skips operators
-
-  For example:
+    * `:only_operators` - include only operators
+    * `:skip_operators` - skip operators
 
       iex> use Bitwise, only_operators: true
       iex> 1 &&& 1
       1
 
-  When invoked with no options, `use Bitwise` is equivalent
-  to `import Bitwise`.
 
-  All bitwise functions can be used in guards:
+  These 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 +46,162 @@ 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.ex

@@ -1,886 +0,0 @@
-defmodule Calendar do
-  @moduledoc """
-  This module defines the responsibilities for working with
-  calendars, dates, times and datetimes in Elixir.
-
-  Currently it defines types and the minimal implementation
-  for a calendar behaviour in Elixir. The goal of the Calendar
-  features in Elixir is to provide a base for interoperability
-  instead of full-featured datetime API.
-
-  For the actual date, time and datetime structures, see `Date`,
-  `Time`, `NaiveDateTime` and `DateTime`.
-
-  Note designations for year, month, day, and the like, are overspecified
-  (i.e. an integer instead of `1..12` for months) because different
-  calendars may have a different number of days per month, months per year and so on.
-  """
-
-  @type year :: integer
-  @type month :: pos_integer
-  @type day :: pos_integer
-  @type week :: pos_integer
-  @type day_of_week :: non_neg_integer
-  @type era :: non_neg_integer
-
-  @typedoc """
-  A tuple representing the `day` and the `era`.
-  """
-  @type day_of_era :: {day :: non_neg_integer(), era}
-
-  @type hour :: non_neg_integer
-  @type minute :: non_neg_integer
-  @type second :: non_neg_integer
-
-  @typedoc """
-  The internal time format is used when converting between calendars.
-
-  It represents time as a fraction of a day (starting from midnight).
-  `parts_in_day` specifies how much of the day is already passed,
-  while `parts_per_day` signifies how many parts there fit in a day.
-  """
-  @type day_fraction :: {parts_in_day :: non_neg_integer, parts_per_day :: pos_integer}
-
-  @typedoc """
-  The internal date format that is used when converting between calendars.
-
-  This is the number of days including the fractional part that has passed of
-  the last day since 0000-01-01+00:00T00:00.000000 in ISO 8601 notation (also
-  known as midnight 1 January BC 1 of the proleptic Gregorian calendar).
-  """
-  @type iso_days :: {days :: integer, day_fraction}
-
-  @typedoc """
-  Microseconds with stored precision.
-
-  The precision represents the number of digits that must be used when
-  representing the microseconds to external format. If the precision is 0,
-  it means microseconds must be skipped.
-  """
-  @type microsecond :: {non_neg_integer, non_neg_integer}
-
-  @typedoc "A calendar implementation"
-  @type calendar :: module
-
-  @typedoc "The time zone ID according to the IANA tz database (for example, Europe/Zurich)"
-  @type time_zone :: String.t()
-
-  @typedoc "The time zone abbreviation (for example, CET or CEST or BST, and such)"
-  @type zone_abbr :: String.t()
-
-  @typedoc """
-  The time zone UTC offset in seconds for standard time.
-
-  See also `t:std_offset/0`.
-  """
-  @type utc_offset :: integer
-
-  @typedoc """
-  The time zone standard offset in seconds (typically not zero in summer times).
-
-  It must be added to `t:utc_offset/0` to get the total offset from UTC used for "wall time".
-  """
-  @type std_offset :: integer
-
-  @typedoc "Any map/struct that contains the date fields"
-  @type date :: %{optional(any) => any, calendar: calendar, year: year, month: month, day: day}
-
-  @typedoc "Any map/struct that contains the time fields"
-  @type time :: %{
-          optional(any) => any,
-          hour: hour,
-          minute: minute,
-          second: second,
-          microsecond: microsecond
-        }
-
-  @typedoc "Any map/struct that contains the naive_datetime fields"
-  @type naive_datetime :: %{
-          optional(any) => any,
-          calendar: calendar,
-          year: year,
-          month: month,
-          day: day,
-          hour: hour,
-          minute: minute,
-          second: second,
-          microsecond: microsecond
-        }
-
-  @typedoc "Any map/struct that contains the datetime fields"
-  @type datetime :: %{
-          optional(any) => any,
-          calendar: calendar,
-          year: year,
-          month: month,
-          day: day,
-          hour: hour,
-          minute: minute,
-          second: second,
-          microsecond: microsecond,
-          time_zone: time_zone,
-          zone_abbr: zone_abbr,
-          utc_offset: utc_offset,
-          std_offset: std_offset
-        }
-
-  @typedoc """
-  Specifies the time zone database for calendar operations.
-
-  Many functions in the `DateTime` module require a time zone database.
-  By default, it uses the default time zone database returned by
-  `Calendar.get_time_zone_database/0`, which defaults to
-  `Calendar.UTCOnlyTimeZoneDatabase` which only handles "Etc/UTC"
-  datetimes and returns `{:error, :utc_only_time_zone_database}`
-  for any other time zone.
-
-  Other time zone databases (including ones provided by packages)
-  can be configured as default either via configuration:
-
-      config :elixir, :time_zone_database, CustomTimeZoneDatabase
-
-  or by calling `Calendar.put_time_zone_database/1`.
-
-  See `Calendar.TimeZoneDatabase` for more information on custom
-  time zone databases.
-  """
-  @type time_zone_database :: module()
-
-  @doc """
-  Returns how many days there are in the given year-month.
-  """
-  @callback days_in_month(year, month) :: day
-
-  @doc """
-  Returns how many months there are in the given year.
-  """
-  @callback months_in_year(year) :: month
-
-  @doc """
-  Returns `true` if the given year is a leap year.
-
-  A leap year is a year of a longer length than normal. The exact meaning
-  is up to the calendar. A calendar must return `false` if it does not support
-  the concept of leap years.
-  """
-  @callback leap_year?(year) :: boolean
-
-  @doc """
-  Calculates the day of the week from the given `year`, `month`, and `day`.
-
-  The `starting_on` represents the starting day of the week. All
-  calendars must support at least the `:default` value. They may
-  also support other values representing their days of the week.
-  """
-  @callback day_of_week(year, month, day, starting_on :: :default | atom) ::
-              {day_of_week(), first_day_of_week :: non_neg_integer(),
-               last_day_of_week :: non_neg_integer()}
-
-  @doc """
-  Calculates the day of the year from the given `year`, `month`, and `day`.
-  """
-  @callback day_of_year(year, month, day) :: non_neg_integer()
-
-  @doc """
-  Calculates the quarter of the year from the given `year`, `month`, and `day`.
-  """
-  @callback quarter_of_year(year, month, day) :: non_neg_integer()
-
-  @doc """
-  Calculates the year and era from the given `year`.
-  """
-  @callback year_of_era(year, month, day) :: {year, era}
-
-  @doc """
-  Calculates the day and era from the given `year`, `month`, and `day`.
-  """
-  @callback day_of_era(year, month, day) :: day_of_era()
-
-  @doc """
-  Converts the date into a string according to the calendar.
-  """
-  @callback date_to_string(year, month, day) :: String.t()
-
-  @doc """
-  Converts the datetime (without time zone) into a string according to the calendar.
-  """
-  @callback naive_datetime_to_string(year, month, day, hour, minute, second, microsecond) ::
-              String.t()
-
-  @doc """
-  Converts the datetime (with time zone) into a string according to the calendar.
-  """
-  @callback datetime_to_string(
-              year,
-              month,
-              day,
-              hour,
-              minute,
-              second,
-              microsecond,
-              time_zone,
-              zone_abbr,
-              utc_offset,
-              std_offset
-            ) :: String.t()
-
-  @doc """
-  Converts the time into a string according to the calendar.
-  """
-  @callback time_to_string(hour, minute, second, microsecond) :: String.t()
-
-  @doc """
-  Converts the given datetime (without time zone) into the `t:iso_days/0` format.
-  """
-  @callback naive_datetime_to_iso_days(year, month, day, hour, minute, second, microsecond) ::
-              iso_days
-
-  @doc """
-  Converts `t:iso_days/0` to the Calendar's datetime format.
-  """
-  @callback naive_datetime_from_iso_days(iso_days) ::
-              {year, month, day, hour, minute, second, microsecond}
-
-  @doc """
-  Converts the given time to the `t:day_fraction/0` format.
-  """
-  @callback time_to_day_fraction(hour, minute, second, microsecond) :: day_fraction
-
-  @doc """
-  Converts `t:day_fraction/0` to the Calendar's time format.
-  """
-  @callback time_from_day_fraction(day_fraction) :: {hour, minute, second, microsecond}
-
-  @doc """
-  Define the rollover moment for the given calendar.
-
-  This is the moment, in your calendar, when the current day ends
-  and the next day starts.
-
-  The result of this function is used to check if two calendars rollover at
-  the same time of day. If they do not, we can only convert datetimes and times
-  between them. If they do, this means that we can also convert dates as well
-  as naive datetimes between them.
-
-  This day fraction should be in its most simplified form possible, to make comparisons fast.
-
-  ## Examples
-
-    * If, in your Calendar, a new day starts at midnight, return {0, 1}.
-    * If, in your Calendar, a new day starts at sunrise, return {1, 4}.
-    * If, in your Calendar, a new day starts at noon, return {1, 2}.
-    * If, in your Calendar, a new day starts at sunset, return {3, 4}.
-
-  """
-  @callback day_rollover_relative_to_midnight_utc() :: day_fraction
-
-  @doc """
-  Should return `true` if the given date describes a proper date in the calendar.
-  """
-  @callback valid_date?(year, month, day) :: boolean
-
-  @doc """
-  Should return `true` if the given time describes a proper time in the calendar.
-  """
-  @callback valid_time?(hour, minute, second, microsecond) :: boolean
-
-  @doc """
-  Parses the string representation for a time returned by `c:time_to_string/4`
-  into a time-tuple.
-  """
-  @doc since: "1.10.0"
-  @callback parse_time(String.t()) ::
-              {:ok, {hour, minute, second, microsecond}}
-              | {:error, atom}
-
-  @doc """
-  Parses the string representation for a date returned by `c:date_to_string/3`
-  into a date-tuple.
-  """
-  @doc since: "1.10.0"
-  @callback parse_date(String.t()) ::
-              {:ok, {year, month, day}}
-              | {:error, atom}
-
-  @doc """
-  Parses the string representation for a naive datetime returned by
-  `c:naive_datetime_to_string/7` into a naive-datetime-tuple.
-
-  The given string may contain a timezone offset but it is ignored.
-  """
-  @doc since: "1.10.0"
-  @callback parse_naive_datetime(String.t()) ::
-              {:ok, {year, month, day, hour, minute, second, microsecond}}
-              | {:error, atom}
-
-  @doc """
-  Parses the string representation for a datetime returned by
-  `c:datetime_to_string/11` into a datetime-tuple.
-
-  The returned datetime must be in UTC. The original `utc_offset`
-  it was written in must be returned in the result.
-  """
-  @doc since: "1.10.0"
-  @callback parse_utc_datetime(String.t()) ::
-              {:ok, {year, month, day, hour, minute, second, microsecond}, utc_offset}
-              | {:error, atom}
-
-  # General Helpers
-
-  @doc """
-  Returns `true` if two calendars have the same moment of starting a new day,
-  `false` otherwise.
-
-  If two calendars are not compatible, we can only convert datetimes and times
-  between them. If they are compatible, this means that we can also convert
-  dates as well as naive datetimes between them.
-  """
-  @doc since: "1.5.0"
-  @spec compatible_calendars?(Calendar.calendar(), Calendar.calendar()) :: boolean
-  def compatible_calendars?(calendar, calendar), do: true
-
-  def compatible_calendars?(calendar1, calendar2) do
-    calendar1.day_rollover_relative_to_midnight_utc() ==
-      calendar2.day_rollover_relative_to_midnight_utc()
-  end
-
-  @doc """
-  Returns a microsecond tuple truncated to a given precision (`:microsecond`,
-  `:millisecond` or `:second`).
-  """
-  @doc since: "1.6.0"
-  @spec truncate(Calendar.microsecond(), :microsecond | :millisecond | :second) ::
-          Calendar.microsecond()
-  def truncate(microsecond_tuple, :microsecond), do: microsecond_tuple
-
-  def truncate({microsecond, precision}, :millisecond) do
-    output_precision = min(precision, 3)
-    {div(microsecond, 1000) * 1000, output_precision}
-  end
-
-  def truncate(_, :second), do: {0, 0}
-
-  @doc """
-  Sets the current time zone database.
-  """
-  @doc since: "1.8.0"
-  @spec put_time_zone_database(time_zone_database()) :: :ok
-  def put_time_zone_database(database) do
-    Application.put_env(:elixir, :time_zone_database, database)
-  end
-
-  @doc """
-  Gets the current time zone database.
-  """
-  @doc since: "1.8.0"
-  @spec get_time_zone_database() :: time_zone_database()
-  def get_time_zone_database() do
-    Application.get_env(:elixir, :time_zone_database, Calendar.UTCOnlyTimeZoneDatabase)
-  end
-
-  @doc """
-  Formats received datetime into a string.
-
-  The datetime can be any of the Calendar types (`Time`, `Date`,
-  `NaiveDateTime`, and `DateTime`) or any map, as long as they
-  contain all of the relevant fields necessary for formatting.
-  For example, if you use `%Y` to format the year, the datetime
-  must have the `:year` field. Therefore, if you pass a `Time`,
-  or a map without the `:year` field to a format that expects `%Y`,
-  an error will be raised.
-
-  ## Options
-
-    * `:preferred_datetime` - a string for the preferred format to show datetimes,
-      it can't contain the `%c` format and defaults to `"%Y-%m-%d %H:%M:%S"`
-      if the option is not received
-
-    * `:preferred_date` - a string for the preferred format to show dates,
-      it can't contain the `%x` format and defaults to `"%Y-%m-%d"`
-      if the option is not received
-
-    * `:preferred_time` - a string for the preferred format to show times,
-      it can't contain the `%X` format and defaults to `"%H:%M:%S"`
-      if the option is not received
-
-    * `:am_pm_names` - a function that receives either `:am` or `:pm` and returns
-      the name of the period of the day, if the option is not received it defaults
-      to a function that returns `"am"` and `"pm"`, respectively
-
-    *  `:month_names` - a function that receives a number and returns the name of
-      the corresponding month, if the option is not received it defaults to a
-      function that returns the month names in English
-
-    * `:abbreviated_month_names` - a function that receives a number and returns the
-      abbreviated name of the corresponding month, if the option is not received it
-      defaults to a function that returns the abbreviated month names in English
-
-    * `:day_of_week_names` - a function that receives a number and returns the name of
-      the corresponding day of week, if the option is not received it defaults to a
-      function that returns the day of week names in English
-
-    * `:abbreviated_day_of_week_names` - a function that receives a number and returns
-      the abbreviated name of the corresponding day of week, if the option is not received
-      it defaults to a function that returns the abbreviated day of week names in English
-
-  ## Formatting syntax
-
-  The formatting syntax for strftime is a sequence of characters in the following format:
-
-      %<padding><width><format>
-
-  where:
-
-    * `%`: indicates the start of a formatted section
-    * `<padding>`: set the padding (see below)
-    * `<width>`: a number indicating the minimum size of the formatted section
-    * `<format>`: the format itself (see below)
-
-  ### Accepted padding options
-
-    * `-`: no padding, removes all padding from the format
-    * `_`: pad with spaces
-    * `0`: pad with zeroes
-
-  ### Accepted formats
-
-  The accepted formats are:
-
-  Format | Description                                                             | Examples (in ISO)
-  :----- | :-----------------------------------------------------------------------| :------------------------
-  a      | Abbreviated name of day                                                 | Mon
-  A      | Full name of day                                                        | Monday
-  b      | Abbreviated month name                                                  | Jan
-  B      | Full month name                                                         | January
-  c      | Preferred date+time representation                                      | 2018-10-17 12:34:56
-  d      | Day of the month                                                        | 01, 31
-  f      | Microseconds *(does not support width and padding modifiers)*           | 000000, 999999, 0123
-  H      | Hour using a 24-hour clock                                              | 00, 23
-  I      | Hour using a 12-hour clock                                              | 01, 12
-  j      | Day of the year                                                         | 001, 366
-  m      | Month                                                                   | 01, 12
-  M      | Minute                                                                  | 00, 59
-  p      | "AM" or "PM" (noon is "PM", midnight as "AM")                           | AM, PM
-  P      | "am" or "pm" (noon is "pm", midnight as "am")                           | am, pm
-  q      | Quarter                                                                 | 1, 2, 3, 4
-  S      | Second                                                                  | 00, 59, 60
-  u      | Day of the week                                                         | 1 (Monday), 7 (Sunday)
-  x      | Preferred date (without time) representation                            | 2018-10-17
-  X      | Preferred time (without date) representation                            | 12:34:56
-  y      | Year as 2-digits                                                        | 01, 01, 86, 18
-  Y      | Year                                                                    | -0001, 0001, 1986
-  z      | +hhmm/-hhmm time zone offset from UTC (empty string if naive)           | +0300, -0530
-  Z      | Time zone abbreviation (empty string if naive)                          | CET, BRST
-  %      | Literal "%" character                                                   | %
-
-  Any other character will be interpreted as an invalid format and raise an error
-
-  ## Examples
-
-  Without options:
-
-      iex> Calendar.strftime(~U[2019-08-26 13:52:06.0Z], "%y-%m-%d %I:%M:%S %p")
-      "19-08-26 01:52:06 PM"
-
-      iex> Calendar.strftime(~U[2019-08-26 13:52:06.0Z], "%a, %B %d %Y")
-      "Mon, August 26 2019"
-
-      iex> Calendar.strftime(~U[2020-04-02 13:52:06.0Z], "%B %-d, %Y")
-      "April 2, 2020"
-
-      iex> Calendar.strftime(~U[2019-08-26 13:52:06.0Z], "%c")
-      "2019-08-26 13:52:06"
-
-  With options:
-
-      iex> Calendar.strftime(~U[2019-08-26 13:52:06.0Z], "%c", preferred_datetime: "%H:%M:%S %d-%m-%y")
-      "13:52:06 26-08-19"
-
-      iex> Calendar.strftime(
-      ...>  ~U[2019-08-26 13:52:06.0Z],
-      ...>  "%A",
-      ...>  day_of_week_names: fn day_of_week ->
-      ...>    {"segunda-feira", "terça-feira", "quarta-feira", "quinta-feira",
-      ...>    "sexta-feira", "sábado", "domingo"}
-      ...>    |> elem(day_of_week - 1)
-      ...>  end
-      ...>)
-      "segunda-feira"
-
-      iex> Calendar.strftime(
-      ...>  ~U[2019-08-26 13:52:06.0Z],
-      ...>  "%B",
-      ...>  month_names: fn month ->
-      ...>    {"январь", "февраль", "март", "апрель", "май", "июнь",
-      ...>    "июль", "август", "сентябрь", "октябрь", "ноябрь", "декабрь"}
-      ...>    |> elem(month - 1)
-      ...>  end
-      ...>)
-      "август"
-  """
-  @doc since: "1.11.0"
-  @spec strftime(map(), String.t(), keyword()) :: String.t()
-  def strftime(date_or_time_or_datetime, string_format, user_options \\ [])
-      when is_map(date_or_time_or_datetime) and is_binary(string_format) do
-    parse(
-      string_format,
-      date_or_time_or_datetime,
-      options(user_options),
-      []
-    )
-    |> IO.iodata_to_binary()
-  end
-
-  defp parse("", _datetime, _format_options, acc),
-    do: Enum.reverse(acc)
-
-  defp parse("%" <> rest, datetime, format_options, acc),
-    do: parse_modifiers(rest, nil, nil, {datetime, format_options, acc})
-
-  defp parse(<<char, rest::binary>>, datetime, format_options, acc),
-    do: parse(rest, datetime, format_options, [char | acc])
-
-  defp parse_modifiers("-" <> rest, width, nil, parser_data) do
-    parse_modifiers(rest, width, "", parser_data)
-  end
-
-  defp parse_modifiers("0" <> rest, width, nil, parser_data) do
-    parse_modifiers(rest, width, ?0, parser_data)
-  end
-
-  defp parse_modifiers("_" <> rest, width, nil, parser_data) do
-    parse_modifiers(rest, width, ?\s, parser_data)
-  end
-
-  defp parse_modifiers(<<digit, rest::binary>>, width, pad, parser_data) when digit in ?0..?9 do
-    new_width = (width || 0) * 10 + (digit - ?0)
-
-    parse_modifiers(rest, new_width, pad, parser_data)
-  end
-
-  # set default padding if none was specified
-  defp parse_modifiers(<<format, _::binary>> = rest, width, nil, parser_data) do
-    parse_modifiers(rest, width, default_pad(format), parser_data)
-  end
-
-  # set default width if none was specified
-  defp parse_modifiers(<<format, _::binary>> = rest, nil, pad, parser_data) do
-    parse_modifiers(rest, default_width(format), pad, parser_data)
-  end
-
-  defp parse_modifiers(rest, width, pad, {datetime, format_options, acc}) do
-    format_modifiers(rest, width, pad, datetime, format_options, acc)
-  end
-
-  defp am_pm(hour, format_options) when hour > 11 do
-    format_options.am_pm_names.(:pm)
-  end
-
-  defp am_pm(hour, format_options) when hour <= 11 do
-    format_options.am_pm_names.(:am)
-  end
-
-  defp default_pad(format) when format in 'aAbBpPZ', do: ?\s
-  defp default_pad(_format), do: ?0
-
-  defp default_width(format) when format in 'dHImMSy', do: 2
-  defp default_width(?j), do: 3
-  defp default_width(format) when format in 'Yz', do: 4
-  defp default_width(_format), do: 0
-
-  # Literally just %
-  defp format_modifiers("%" <> rest, width, pad, datetime, format_options, acc) do
-    parse(rest, datetime, format_options, [pad_leading("%", width, pad) | acc])
-  end
-
-  # Abbreviated name of day
-  defp format_modifiers("a" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      datetime
-      |> Date.day_of_week()
-      |> format_options.abbreviated_day_of_week_names.()
-      |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Full name of day
-  defp format_modifiers("A" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      datetime
-      |> Date.day_of_week()
-      |> format_options.day_of_week_names.()
-      |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Abbreviated month name
-  defp format_modifiers("b" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      datetime.month
-      |> format_options.abbreviated_month_names.()
-      |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Full month name
-  defp format_modifiers("B" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.month |> format_options.month_names.() |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Preferred date+time representation
-  defp format_modifiers(
-         "c" <> _rest,
-         _width,
-         _pad,
-         _datetime,
-         %{preferred_datetime_invoked: true},
-         _acc
-       ) do
-    raise ArgumentError,
-          "tried to format preferred_datetime within another preferred_datetime format"
-  end
-
-  defp format_modifiers("c" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      format_options.preferred_datetime
-      |> parse(datetime, %{format_options | preferred_datetime_invoked: true}, [])
-      |> pad_preferred(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Day of the month
-  defp format_modifiers("d" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.day |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Microseconds
-  defp format_modifiers("f" <> rest, _width, _pad, datetime, format_options, acc) do
-    {microsecond, precision} = datetime.microsecond
-
-    result =
-      microsecond
-      |> Integer.to_string()
-      |> String.pad_leading(6, "0")
-      |> binary_part(0, max(precision, 1))
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Hour using a 24-hour clock
-  defp format_modifiers("H" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.hour |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Hour using a 12-hour clock
-  defp format_modifiers("I" <> rest, width, pad, datetime, format_options, acc) do
-    result = (rem(datetime.hour() + 23, 12) + 1) |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Day of the year
-  defp format_modifiers("j" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime |> Date.day_of_year() |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Month
-  defp format_modifiers("m" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.month |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Minute
-  defp format_modifiers("M" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.minute |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # "AM" or "PM" (noon is "PM", midnight as "AM")
-  defp format_modifiers("p" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.hour |> am_pm(format_options) |> String.upcase() |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # "am" or "pm" (noon is "pm", midnight as "am")
-  defp format_modifiers("P" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      datetime.hour
-      |> am_pm(format_options)
-      |> String.downcase()
-      |> pad_leading(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Quarter
-  defp format_modifiers("q" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime |> Date.quarter_of_year() |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Second
-  defp format_modifiers("S" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.second |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Day of the week
-  defp format_modifiers("u" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime |> Date.day_of_week() |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Preferred date (without time) representation
-  defp format_modifiers(
-         "x" <> _rest,
-         _width,
-         _pad,
-         _datetime,
-         %{preferred_date_invoked: true},
-         _acc
-       ) do
-    raise ArgumentError,
-          "tried to format preferred_date within another preferred_date format"
-  end
-
-  defp format_modifiers("x" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      format_options.preferred_date
-      |> parse(datetime, %{format_options | preferred_date_invoked: true}, [])
-      |> pad_preferred(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Preferred time (without date) representation
-  defp format_modifiers(
-         "X" <> _rest,
-         _width,
-         _pad,
-         _datetime,
-         %{preferred_time_invoked: true},
-         _acc
-       ) do
-    raise ArgumentError,
-          "tried to format preferred_time within another preferred_time format"
-  end
-
-  defp format_modifiers("X" <> rest, width, pad, datetime, format_options, acc) do
-    result =
-      format_options.preferred_time
-      |> parse(datetime, %{format_options | preferred_time_invoked: true}, [])
-      |> pad_preferred(width, pad)
-
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Year as 2-digits
-  defp format_modifiers("y" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.year |> rem(100) |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # Year
-  defp format_modifiers("Y" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime.year |> Integer.to_string() |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  # +hhmm/-hhmm time zone offset from UTC (empty string if naive)
-  defp format_modifiers(
-         "z" <> rest,
-         width,
-         pad,
-         datetime = %{utc_offset: utc_offset, std_offset: std_offset},
-         format_options,
-         acc
-       ) do
-    absolute_offset = abs(utc_offset + std_offset)
-
-    offset_number =
-      Integer.to_string(div(absolute_offset, 3600) * 100 + rem(div(absolute_offset, 60), 60))
-
-    sign = if utc_offset + std_offset >= 0, do: "+", else: "-"
-    result = "#{sign}#{pad_leading(offset_number, width, pad)}"
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  defp format_modifiers("z" <> rest, _width, _pad, datetime, format_options, acc) do
-    parse(rest, datetime, format_options, ["" | acc])
-  end
-
-  # Time zone abbreviation (empty string if naive)
-  defp format_modifiers("Z" <> rest, width, pad, datetime, format_options, acc) do
-    result = datetime |> Map.get(:zone_abbr, "") |> pad_leading(width, pad)
-    parse(rest, datetime, format_options, [result | acc])
-  end
-
-  defp format_modifiers(rest, _width, _pad, _datetime, _format_options, _acc) do
-    {next, _rest} = String.next_grapheme(rest) || {"", ""}
-    raise ArgumentError, "invalid strftime format: %#{next}"
-  end
-
-  defp pad_preferred(result, width, pad) when length(result) < width do
-    pad_preferred([pad | result], width, pad)
-  end
-
-  defp pad_preferred(result, _width, _pad), do: result
-
-  defp pad_leading(string, count, padding) do
-    to_pad = count - byte_size(string)
-    if to_pad > 0, do: do_pad_leading(to_pad, padding, string), else: string
-  end
-
-  defp do_pad_leading(0, _, acc), do: acc
-
-  defp do_pad_leading(count, padding, acc),
-    do: do_pad_leading(count - 1, padding, [padding | acc])
-
-  defp options(user_options) do
-    default_options = %{
-      preferred_date: "%Y-%m-%d",
-      preferred_time: "%H:%M:%S",
-      preferred_datetime: "%Y-%m-%d %H:%M:%S",
-      am_pm_names: fn
-        :am -> "am"
-        :pm -> "pm"
-      end,
-      month_names: fn month ->
-        {"January", "February", "March", "April", "May", "June", "July", "August", "September",
-         "October", "November", "December"}
-        |> elem(month - 1)
-      end,
-      day_of_week_names: fn day_of_week ->
-        {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"}
-        |> elem(day_of_week - 1)
-      end,
-      abbreviated_month_names: fn month ->
-        {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"}
-        |> elem(month - 1)
-      end,
-      abbreviated_day_of_week_names: fn day_of_week ->
-        {"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"} |> elem(day_of_week - 1)
-      end,
-      preferred_datetime_invoked: false,
-      preferred_date_invoked: false,
-      preferred_time_invoked: false
-    }
-
-    Enum.reduce(user_options, default_options, fn {key, value}, acc ->
-      if Map.has_key?(acc, key) do
-        %{acc | key => value}
-      else
-        raise ArgumentError, "unknown option #{inspect(key)} given to Calendar.strftime/3"
-      end
-    end)
-  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, file, 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

@@ -1,559 +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({:<<>>, _, _} = quoted, state) do
-    normalize_bitstring(quoted, state)
-  end
-
-  # Atoms with interpolations
-  defp do_normalize(
-         {{:., dot_meta, [:erlang, :binary_to_atom]}, call_meta, [{:<<>>, _, _} = string, :utf8]},
-         state
-       ) 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, [{:<<>>, _, _} = string, modifiers]} = quoted, state)
-       when 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) do
-    {last_arg, args} = List.pop_at(args, -1)
-
-    with [{{:__block__, key_meta, _}, _} | _] <- last_arg, :keyword <- key_meta[:format] do
-      args = normalize_kw_args(args, state)
-      kw_list = normalize_kw_args(last_arg, state)
-      {:{}, meta, args ++ kw_list}
-    else
-      _ ->
-        normalize_call(quoted, state)
-    end
-  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
-      "Elixir." <> segments = Atom.to_string(literal)
-
-      segments =
-        segments
-        |> String.split(".")
-        |> Enum.map(&String.to_atom/1)
-
-      {:__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}
-
-    with [{{:__block__, key_meta, _}, _} | _] <- right, :keyword <- key_meta[:format] do
-      {:__block__, meta, [{do_normalize(left, state), normalize_kw_args(right, state)}]}
-    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)]}
-    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), 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? \\ false)
-
-  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

@@ -13,167 +13,65 @@ defprotocol Collectable do
   The `Enumerable` protocol is useful to take values out of a collection.
   In order to support a wide range of values, the functions provided by
   the `Enumerable` protocol do not keep shape. For example, passing a
-  map to `Enum.map/2` always returns a list.
+  dictionary to `Enum.map/2` always returns a list.
 
   This design is intentional. `Enumerable` was designed to support infinite
   collections, resources and other structures with fixed shape. For example,
-  it doesn't make sense to insert values into a `Range`, as it has a
-  fixed shape where 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 +9,50 @@ 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: Remove callbacks on 1.3
+  # TODO: Deprecate every function on 1.3
+  @callback new :: t
+  @callback delete(t, key) :: t
+  @callback drop(t, Enum.t) :: t
+  @callback equal?(t, t) :: boolean
+  @callback get(t, key) :: value
+  @callback get(t, key, value) :: value
+  @callback get_lazy(t, key, (() -> value)) :: value
+  @callback get_and_update(t, key, (value -> {value, value})) :: {value, t}
+  @callback fetch(t, key) :: {:ok, value} | :error
+  @callback fetch!(t, key) :: value | no_return
+  @callback has_key?(t, key) :: boolean
+  @callback keys(t) :: [key]
+  @callback merge(t, t) :: t
+  @callback merge(t, t, (key, value, value -> value)) :: t
+  @callback pop(t, key) :: {value, t}
+  @callback pop(t, key, value) :: {value, t}
+  @callback pop_lazy(t, key, (() -> value)) :: {value, t}
+  @callback put(t, key, value) :: t
+  @callback put_new(t, key, value) :: t
+  @callback put_new_lazy(t, key, (() -> value)) :: t
+  @callback size(t) :: non_neg_integer()
+  @callback split(t, Enum.t) :: {t, t}
+  @callback take(t, Enum.t) :: t
+  @callback to_list(t) :: list()
+  @callback update(t, key, value, (value -> value)) :: t
+  @callback update!(t, key, (value -> value)) :: t | no_return
+  @callback values(t) :: list(value)
 
   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"
+      @behaviour Dict
 
-      @deprecated message
       def get(dict, key, default \\ nil) do
         case fetch(dict, key) do
           {:ok, value} -> value
@@ -37,7 +60,6 @@ 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 +67,12 @@ 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
@@ -60,35 +80,30 @@ 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 ->
+        Enum.reduce(keys, new, fn key, acc ->
           case fetch(dict, key) do
             {:ok, value} -> put(acc, key, value)
             :error -> acc
@@ -96,49 +111,41 @@ 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 +157,144 @@ 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 ->
+        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 +303,10 @@ 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 +320,51 @@ 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)
@@ -417,27 +375,24 @@ 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)
   end
 
-  @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.
@@ -32,20 +32,20 @@ defmodule File.Stat do
       systems which have no concept of links.
 
     * `major_device` - identifies the file system where the file is located.
-      In Windows, the number indicates a drive as follows: 0 means A:, 1 means
+      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
+      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

@@ -2,109 +2,30 @@ 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)
-
   @doc """
   Parses a binary into a float.
 
-  If successful, returns a tuple in the form of `{float, remainder_of_binary}`;
+  If successful, returns a tuple of the form `{float, remainder_of_binary}`;
   when the binary cannot be coerced into a valid float, the atom `:error` is
   returned.
 
   If the size of float exceeds the maximum size of `1.7976931348623157e+308`,
   the `ArgumentError` exception is raised.
 
-  If you want to convert a string-formatted float directly to a float,
+  If a float formatted string wants to be directly converted to a float,
   `String.to_float/1` can be used instead.
 
   ## Examples
 
       iex> Float.parse("34")
       {34.0, ""}
+
       iex> Float.parse("34.25")
       {34.25, ""}
+
       iex> Float.parse("56.5xyz")
       {56.5, "xyz"}
 
@@ -128,98 +49,66 @@ 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)
-      12.51
-
-  One may have expected it to floor to 12.52. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as 12.51999999,
-  which explains the behaviour above.
-
   ## Examples
 
       iex> Float.floor(34.25)
       34.0
+
       iex> Float.floor(-56.5)
       -57.0
+
       iex> Float.floor(34.259, 2)
       34.25
 
   """
-  @spec floor(float, 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
-    round(number, precision, :floor)
-  end
-
-  def floor(number, precision) when is_float(number) do
-    raise ArgumentError, invalid_precision_message(precision)
+  @spec floor(float, 0..15) :: float
+  def floor(number, precision \\ 0) when is_float(number) and precision in 0..15 do
+    power     = power_of_10(precision)
+    number    = number * power
+    truncated = trunc(number)
+    variance  = if number - truncated < 0, do: -1.0, else: 0.0
+    (truncated + variance) / power
   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
-  conversion to decimal.
-
-  The behaviour of `ceil/2` for floats can be surprising. For example:
-
-      iex> Float.ceil(-12.52, 2)
-      -12.51
-
-  One may have expected it to ceil to -12.52. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as -12.51999999,
-  which explains the behaviour above.
-
   This function always returns floats. `Kernel.trunc/1` may be used instead to
   truncate the result to an integer afterwards.
 
@@ -227,349 +116,136 @@ defmodule Float do
 
       iex> Float.ceil(34.25)
       35.0
+
       iex> Float.ceil(-56.5)
       -56.0
+
       iex> Float.ceil(34.251, 2)
       34.26
 
   """
-  @spec ceil(float, 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
-    round(number, precision, :ceil)
-  end
-
-  def ceil(number, precision) when is_float(number) do
-    raise ArgumentError, invalid_precision_message(precision)
+  @spec ceil(float, 0..15) :: float
+  def ceil(number, precision \\ 0) when is_float(number) and precision in 0..15 do
+    power     = power_of_10(precision)
+    number    = number * power
+    truncated = trunc(number)
+    variance  = if number - truncated > 0, do: 1.0, else: 0.0
+    (truncated + variance) / power
   end
 
   @doc """
-  Rounds a floating-point value to an arbitrary number of fractional
-  digits (between 0 and 15).
-
-  The rounding direction always ties to half up. The operation is
-  performed on the binary floating point, without a conversion to decimal.
+  Rounds a floating point value to an arbitrary number of fractional digits
+  (between 0 and 15).
 
   This function only accepts floats and always returns a float. Use
-  `Kernel.round/1` if you want a function that accepts both floats
-  and integers and always returns an integer.
-
-  ## Known issues
-
-  The behaviour of `round/2` for floats can be surprising. For example:
-
-      iex> Float.round(5.5675, 3)
-      5.567
-
-  One may have expected it to round to the half up 5.568. This is not a bug.
-  Most decimal fractions cannot be represented as a binary floating point
-  and therefore the number above is internally represented as 5.567499999,
-  which explains the behaviour above. If you want exact rounding for decimals,
-  you must use a decimal library. The behaviour above is also in accordance
-  to reference implementations, such as "Correctly Rounded Binary-Decimal and
-  Decimal-Binary Conversions" by David M. Gay.
+  `Kernel.round/1` if you want a function that accepts both floats and integers
+  and always returns an integer.
 
   ## Examples
 
-      iex> Float.round(12.5)
-      13.0
       iex> Float.round(5.5674, 3)
       5.567
+
       iex> Float.round(5.5675, 3)
-      5.567
+      5.568
+
       iex> Float.round(-5.5674, 3)
       -5.567
-      iex> Float.round(-5.5675)
-      -6.0
-      iex> Float.round(12.341444444444441, 15)
-      12.341444444444441
+
+      iex> Float.round(-5.5675, 3)
+      -5.568
 
   """
-  @spec round(float, precision_range) :: 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()
+  @spec round(float, 0..15) :: float
+  def round(number, precision \\ 0) when is_float(number) and precision in 0..15 do
+    power = power_of_10(precision)
+    Kernel.round(number * power) / power
   end
 
-  def round(float, precision) when is_float(float) and precision in @precision_range 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)
-    count = count - exp + 1023
-
-    cond do
-      # Precision beyond 15 digits
-      count >= 104 ->
-        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 ->
-        float
-
-      true ->
-        # Difference in precision between float and asked precision
-        # We subtract 1 because we need to calculate the remainder too
-        diff = count - precision - 1
-
-        # Get up to latest so we calculate the remainder
-        power_of_10 = power_of_10(diff)
-
-        # Convert the numerand to decimal base
-        num = num * power_of_5(count)
-
-        # Move to the given precision - 1
-        num = div(num, power_of_10)
-        div = div(num, 10)
-        num = rounding(rounding, sign, num, div)
-
-        # Convert back to float without loss
-        # https://www.exploringbinary.com/correct-decimal-to-floating-point-using-big-integers/
-        den = power_of_10(precision)
-        boundary = den <<< 52
-
-        cond do
-          num == 0 ->
-            0.0
-
-          num >= boundary ->
-            {den, exp} = scale_down(num, boundary, 52)
-            decimal_to_float(sign, num, den, exp)
-
-          true ->
-            {num, exp} = scale_up(num, boundary, 52)
-            decimal_to_float(sign, num, den, exp)
-        end
-    end
-  end
-
-  defp 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
-      scale_down(num, new_den, exp + 1)
-    end
-  end
-
-  defp decimal_to_float(sign, num, den, exp) do
-    quo = div(num, den)
-    rem = num - quo * den
-
-    tmp =
-      case den >>> 1 do
-        den when rem > den -> quo + 1
-        den when rem < den -> quo
-        _ when (quo &&& 1) === 1 -> quo + 1
-        _ -> quo
-      end
-
-    tmp = tmp - @power_of_2_to_52
-    <<tmp::float>> = <<sign::1, exp + 1023::11, tmp::52>>
-    tmp
-  end
-
-  defp rounding(:floor, 1, _num, div), do: div + 1
-  defp rounding(:ceil, 0, _num, div), do: div + 1
-
-  defp rounding(:half_up, _sign, num, div) do
-    case rem(num, 10) do
-      rem when rem < 5 -> div
-      rem when rem >= 5 -> div + 1
-    end
-  end
-
-  defp rounding(_, _, _, div), do: div
-
-  Enum.reduce(0..104, 1, fn x, acc ->
+  Enum.reduce 0..15, 1, fn x, acc ->
     defp power_of_10(unquote(x)), do: unquote(acc)
     acc * 10
-  end)
-
-  Enum.reduce(0..104, 1, fn x, acc ->
-    defp power_of_5(unquote(x)), do: unquote(acc)
-    acc * 5
-  end)
-
-  @doc """
-  Returns a pair of integers whose ratio is exactly equal
-  to the original float and with a positive denominator.
-
-  ## Examples
-
-      iex> Float.ratio(0.0)
-      {0, 1}
-      iex> Float.ratio(3.14)
-      {7070651414971679, 2251799813685248}
-      iex> Float.ratio(-3.14)
-      {-7070651414971679, 2251799813685248}
-      iex> Float.ratio(1.5)
-      {3, 2}
-      iex> Float.ratio(-1.5)
-      {-3, 2}
-      iex> Float.ratio(16.0)
-      {16, 1}
-      iex> Float.ratio(-16.0)
-      {-16, 1}
-
-  """
-  @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}
-    end
   end
 
-  defp root_factors(mantissa, count) when mantissa != 0 and (mantissa &&& 1) == 0,
-    do: root_factors(mantissa >>> 1, count + 1)
-
-  defp root_factors(mantissa, count),
-    do: {mantissa, count}
-
-  @compile {:inline, sign: 2}
-  defp sign(0, num), do: num
-  defp sign(1, num), do: -num
-
   @doc """
-  Returns a charlist which corresponds to the text representation
-  of the given float.
+  Returns a char list which corresponds to the text representation of the given float.
 
-  It uses the shortest representation according to algorithm described
-  in "Printing Floating-Point Numbers Quickly and Accurately" in
-  Proceedings of the SIGPLAN '96 Conference on Programming Language
-  Design and Implementation.
+  Inlined by the compiler.
 
   ## Examples
 
-      iex> Float.to_charlist(7.0)
-      '7.0'
+      iex> Float.to_char_list(7.0)
+      '7.00000000000000000000e+00'
 
   """
-  @spec to_charlist(float) :: charlist
-  def to_charlist(float) when is_float(float) do
-    :io_lib_format.fwrite_g(float)
+  @spec to_char_list(float) :: char_list
+  def to_char_list(float) do
+    :erlang.float_to_list(float)
+  end
+
+  @doc """
+  Returns a list which corresponds to the text representation
+  of the given float.
+
+  ## Options
+
+    * `:decimals`   - number of decimal points to show
+    * `:scientific` - number of decimal points to show, in scientific format
+    * `:compact`    - when `true`, use the most compact representation (ignored
+      with the `scientific` option)
+
+  ## Examples
+
+      iex> Float.to_char_list 7.1, [decimals: 2, compact: true]
+      '7.1'
+
+  """
+  @spec to_char_list(float, list) :: char_list
+  def to_char_list(float, options) do
+    :erlang.float_to_list(float, expand_compact(options))
   end
 
   @doc """
   Returns a binary which corresponds to the text representation
   of the given float.
 
-  It uses the shortest representation according to algorithm described
-  in "Printing Floating-Point Numbers Quickly and Accurately" in
-  Proceedings of the SIGPLAN '96 Conference on Programming Language
-  Design and Implementation.
+  Inlined by the compiler.
 
   ## Examples
 
       iex> Float.to_string(7.0)
-      "7.0"
+      "7.00000000000000000000e+00"
 
   """
-  @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))
+  @spec to_string(float) :: String.t
+  def to_string(float) do
+    :erlang.float_to_binary(float)
   end
 
-  @doc false
-  @deprecated "Use Float.to_charlist/1 instead"
-  def to_char_list(float), do: Float.to_charlist(float)
+  @doc """
+  Returns a binary which corresponds to the text representation
+  of `float`.
 
-  @doc false
-  @deprecated "Use :erlang.float_to_list/2 instead"
-  def to_char_list(float, options) do
-    :erlang.float_to_list(float, expand_compact(options))
-  end
+  ## Options
 
-  @doc false
-  @deprecated "Use :erlang.float_to_binary/2 instead"
+    * `:decimals`   - number of decimal points to show
+    * `:scientific` - number of decimal points to show, in scientific format
+    * `:compact`    - when `true`, use the most compact representation (ignored
+      with the `scientific` option)
+
+  ## Examples
+
+      iex> Float.to_string 7.1, [decimals: 2, compact: true]
+      "7.1"
+
+  """
+  @spec to_string(float, list) :: String.t
   def to_string(float, options) do
     :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, false}|t]), do: expand_compact(t)
+  defp expand_compact([{:compact, true}|t]),  do: [:compact|expand_compact(t)]
+  defp expand_compact([h|t]),                 do: [h|expand_compact(t)]
+  defp expand_compact([]),                    do: []
 end

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

@@ -1,8 +1,19 @@
 defmodule GenEvent.Stream do
-  @moduledoc false
+  @moduledoc """
+  Defines a `GenEvent` stream.
+
+  This is a struct returned by `GenEvent.stream/2`. The struct is public and
+  contains the following fields:
+
+    * `:manager`  - the manager reference given to `GenEvent.stream/2`
+    * `:timeout`  - the timeout between events, defaults to `:infinity`
+
+  """
   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
@@ -11,7 +22,7 @@ defmodule GenEvent.Stream do
 
   @doc false
   def handle_event(event, _state) do
-    # We do this to trick Dialyzer to not complain about non-local returns.
+    # We do this to trick dialyzer to not complain about non-local returns.
     case :erlang.phash2(1, 1) do
       0 -> exit({:bad_event, event})
       1 -> :remove_handler
@@ -20,9 +31,8 @@ defmodule GenEvent.Stream do
 
   @doc false
   def handle_call(msg, _state) do
-    # We do this to trick Dialyzer to not complain about non-local returns.
+    # 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 +57,7 @@ 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 +71,26 @@ 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 +138,6 @@ 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 +146,7 @@ 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 +155,6 @@ 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 +162,7 @@ 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

@@ -1,12 +1,10 @@
 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"
-
   use Dict
 
   @node_bitmap 0b111
@@ -22,70 +20,58 @@ 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 +81,7 @@ 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
 
@@ -103,105 +89,86 @@ 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, [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}
-
-      [^key | value] ->
-        {put_elem(node, index, [key | fun.(value)]), 0}
-
-      [k | v] ->
-        n = put_elem(@node_template, key_mask(key_shift(hash)), [key | default.()])
+        {put_elem(node, index, [key|initial.()]), 1}
+      [^key|value] ->
+        {put_elem(node, index, [key|fun.(value)]), 0}
+      [k|v] ->
+        n = put_elem(@node_template, key_mask(key_shift(hash)), [key|initial.()])
         {put_elem(node, index, {k, v, n}), 1}
-
       {^key, value, n} ->
         {put_elem(node, index, {key, fun.(value), n}), 0}
-
       {k, v, n} ->
-        {n, counter} = do_update(n, key, 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] ->
+      [^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}
-
+            {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] ->
+        [k|v] ->
           case put_elem(node, unquote(index), []) do
-            @node_template -> [k | v]
+            @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
 
@@ -217,7 +184,7 @@ defmodule HashDict do
     next.(acc)
   end
 
-  defp do_reduce_each([k | v], {:cont, acc}, fun, next) do
+  defp do_reduce_each([k|v], {:cont, acc}, fun, next) do
     next.(fun.({k, v}, acc))
   end
 
@@ -226,12 +193,7 @@ 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 +218,19 @@ 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 +238,6 @@ 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"
+  @behaviour Set
 
   @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
@@ -128,85 +111,72 @@ defmodule HashSet do
 
   defp do_member?(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
-      [] -> false
-      [^term | _] -> true
-      [_] -> false
-      [_ | n] -> do_member?(n, term, key_shift(hash))
+      []        -> false
+      [^term|_] -> true
+      [_]       -> false
+      [_|n]     -> do_member?(n, term, key_shift(hash))
     end
   end
 
   defp do_put(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         {put_elem(node, index, [term]), 1}
-
-      [^term | _] ->
+      [^term|_] ->
         {node, 0}
-
       [t] ->
         n = put_elem(@node_template, key_mask(key_shift(hash)), [term])
-        {put_elem(node, index, [t | n]), 1}
-
-      [t | n] ->
+        {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}
+        {put_elem(node, index, [t|n]), counter}
     end
   end
 
   defp do_delete(node, term, hash) do
     index = key_mask(hash)
-
     case elem(node, index) do
       [] ->
         :error
-
       [^term] ->
         {:ok, put_elem(node, index, [])}
-
       [_] ->
         :error
-
-      [^term | n] ->
+      [^term|n] ->
         {:ok, put_elem(node, index, do_compact_node(n))}
-
-      [t | 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])}
-
+            {: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] ->
           case put_elem(node, unquote(index), []) do
             @node_template -> [t]
-            n -> [t | n]
+            n -> [t|n]
           end
-
-        [t | n] ->
-          [t | put_elem(node, unquote(index), do_compact_node(n))]
+        [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([t | n], acc, fun), do: do_fold(n, fun.(t, acc), fun, @node_size)
+  defp do_fold_each([], acc, _fun),   do: acc
+  defp do_fold_each([t], acc, fun),   do: fun.(t, acc)
+  defp do_fold_each([t|n], acc, fun), do: do_fold(n, fun.(t, acc), fun, @node_size)
 
   defp do_fold(node, acc, fun, count) when count > 0 do
     acc = do_fold_each(:erlang.element(count, node), acc, fun)
@@ -235,17 +205,12 @@ defmodule HashSet do
     next.(fun.(t, acc))
   end
 
-  defp do_reduce_each([t | n], {:cont, acc}, fun, next) do
+  defp do_reduce_each([t|n], {:cont, acc}, fun, next) do
     do_reduce(n, fun.(t, acc), fun, @node_size, next)
   end
 
   defp do_reduce(node, acc, fun, count, next) when count > 0 do
-    do_reduce_each(
-      :erlang.element(count, node),
-      acc,
-      fun,
-      &do_reduce(node, &1, fun, count - 1, next)
-    )
+    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` 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
 
@@ -49,325 +44,432 @@ 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)
+  def inspect(thing, opts)
 end
 
 defimpl Inspect, for: Atom do
   require Macro
 
-  def inspect(atom, opts) do
-    color(Identifier.inspect_as_atom(atom), color_key(atom), opts)
+  def inspect(atom, _opts) do
+    inspect(atom)
   end
 
-  defp color_key(atom) when is_boolean(atom), do: :boolean
-  defp color_key(nil), do: nil
-  defp color_key(_), do: :atom
-end
+  def inspect(false),  do: "false"
+  def inspect(true),   do: "true"
+  def inspect(nil),    do: "nil"
+  def inspect(:""),    do: ":\"\""
 
-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
+  def inspect(atom) do
+    binary = Atom.to_string(atom)
 
-    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, ?", " <> ..."]
+    cond do
+      valid_ref_identifier?(binary) ->
+        if only_elixir?(binary) do
+          binary
+        else
+          "Elixir." <> rest = binary
+          rest
         end
-
-      color(IO.iodata_to_binary(inspected), :string, opts)
-    else
-      inspect_bitstring(term, opts)
+      valid_atom_identifier?(binary) ->
+        ":" <> binary
+      atom in [:%{}, :{}, :<<>>, :..., :%] ->
+        ":" <> binary
+      atom in Macro.binary_ops or atom in Macro.unary_ops ->
+        ":" <> binary
+      true ->
+        <<?:, ?", Inspect.BitString.escape(binary, ?")::binary, ?">>
     end
   end
 
-  def inspect(term, opts) do
-    inspect_bitstring(term, opts)
+  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 inspect_bitstring("", opts) do
-    color("<<>>", :binary, opts)
+  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(thing, %Inspect.Opts{binaries: bins} = opts) when is_binary(thing) do
+    if bins == :as_strings or (bins == :infer and String.printable?(thing)) do
+      <<?", escape(thing, ?")::binary, ?">>
+    else
+      inspect_bitstring(thing, opts)
+    end
+  end
+
+  def inspect(thing, opts) do
+    inspect_bitstring(thing, opts)
+  end
+
+  ## Escaping
+
+  @doc false
+  def escape(other, char) do
+    escape(other, char, <<>>)
+  end
+
+  defp escape(<<char, t::binary >>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, char>>)
+  end
+  defp escape(<<?#, ?{, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?#, ?{>>)
+  end
+  defp escape(<<?\a, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?a>>)
+  end
+  defp escape(<<?\b, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?b>>)
+  end
+  defp escape(<<?\d, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?d>>)
+  end
+  defp escape(<<?\e, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?e>>)
+  end
+  defp escape(<<?\f, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?f>>)
+  end
+  defp escape(<<?\n, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?n>>)
+  end
+  defp escape(<<?\r, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?r>>)
+  end
+  defp escape(<<?\\, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?\\>>)
+  end
+  defp escape(<<?\t, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?t>>)
+  end
+  defp escape(<<?\v, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, ?\\, ?v>>)
+  end
+  defp escape(<<h::utf8, t::binary>>, char, binary) do
+    head = <<h::utf8 >>
+    if String.printable?(head) do
+      escape(t, char, append(head, binary))
+    else
+      <<byte::8, h::binary >> = head
+      t = <<h::binary, t::binary>>
+      escape(t, char, <<binary::binary, escape_char(byte)::binary>>)
+    end
+  end
+  defp escape(<<h, t::binary>>, char, binary) do
+    escape(t, char, <<binary::binary, escape_char(h)::binary>>)
+  end
+  defp escape(<<>>, _char, binary), do: binary
+
+  @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
+
+  defp append(<<h, t::binary>>, binary), do: append(t, <<binary::binary, h>>)
+  defp append(<<>>, binary), do: binary
+
+  ## Bitstrings
+
   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))
+    each_bit(bitstring, opts.limit, "<<") <> ">>"
   end
 
-  defp each_bit(_, 0, _) do
-    "..."
+  defp each_bit(_, 0, acc) do
+    acc <> "..."
   end
 
-  defp each_bit(<<>>, _counter, _opts) do
-    :doc_nil
+  defp each_bit(<<h, t::bitstring>>, counter, acc) when t != <<>> do
+    each_bit(t, decrement(counter), acc <> Integer.to_string(h) <> ", ")
   end
 
-  defp each_bit(<<h::8>>, _counter, opts) do
-    Inspect.Integer.inspect(h, opts)
+  defp each_bit(<<h::8>>, _counter, acc) do
+    acc <> Integer.to_string(h)
   end
 
-  defp each_bit(<<h, t::bitstring>>, counter, opts) do
-    flex_glue(
-      concat(Inspect.Integer.inspect(h, opts), ","),
-      each_bit(t, decrement(counter), opts)
-    )
+  defp each_bit(<<>>, _counter, acc) do
+    acc
   end
 
-  defp each_bit(bitstring, _counter, opts) do
+  defp each_bit(bitstring, _counter, acc) do
     size = bit_size(bitstring)
     <<h::size(size)>> = bitstring
-    concat(Inspect.Integer.inspect(h, opts), "::size(" <> Integer.to_string(size) <> ")")
+    acc <> Integer.to_string(h) <> "::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
-  def inspect([], opts) 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
-
-    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
-        lists
-      end
-
-    open = color("[", :list, opts)
-    sep = color(",", :list, opts)
-    close = color("]", :list, opts)
+  def inspect([], _opts), do: "[]"
 
+  def inspect(thing, %Inspect.Opts{char_lists: lists} = opts) do
     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)
-
-      keyword?(term) ->
-        container_doc(open, term, close, opts, &keyword/2, separator: sep, break: :strict)
-
+      lists == :as_char_lists or (lists == :infer and printable?(thing)) ->
+        <<?', Inspect.BitString.escape(IO.chardata_to_string(thing), ?')::binary, ?'>>
+      keyword?(thing) ->
+        surround_many("[", thing, "]", opts, &keyword/2)
       true ->
-        container_doc(open, term, close, opts, &to_doc/2, separator: sep)
+        surround_many("[", thing, "]", opts, &to_doc/2)
     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)))
+    concat(
+      key_to_binary(key) <> ": ",
+      to_doc(value, opts)
+    )
   end
 
   @doc false
   def keyword?([{key, _value} | rest]) when is_atom(key) do
-    case Atom.to_charlist(key) do
+    case Atom.to_char_list(key) do
       'Elixir.' ++ _ -> false
       _ -> keyword?(rest)
     end
   end
 
-  def keyword?([]), do: true
+  def keyword?([]),     do: true
   def keyword?(_other), do: false
+
+  @doc false
+  def printable?([c|cs]) when is_integer(c) and c in 32..126, do: printable?(cs)
+  def printable?([?\n|cs]), do: printable?(cs)
+  def printable?([?\r|cs]), do: printable?(cs)
+  def printable?([?\t|cs]), do: printable?(cs)
+  def printable?([?\v|cs]), do: printable?(cs)
+  def printable?([?\b|cs]), do: printable?(cs)
+  def printable?([?\f|cs]), do: printable?(cs)
+  def printable?([?\e|cs]), do: printable?(cs)
+  def printable?([?\a|cs]), do: printable?(cs)
+  def printable?([]), do: true
+  def printable?(_), do: false
+
+  ## Private
+
+  defp key_to_binary(key) do
+    case Inspect.Atom.inspect(key) do
+      ":" <> right -> right
+      other -> other
+    end
+  end
 end
 
 defimpl Inspect, for: Tuple do
+  def inspect({}, _opts), do: "{}"
+
   def inspect(tuple, opts) 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("{", Tuple.to_list(tuple), "}", opts, &to_doc/2)
   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)
-    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)
+    map = :maps.to_list(map)
+    surround_many("%" <> name <> "{", map, "}", opts, traverse_fun(map))
   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
 
 defimpl Inspect, for: Integer do
-  def inspect(term, %Inspect.Opts{base: base} = opts) do
-    inspected = Integer.to_string(term, base_to_value(base)) |> prepend_prefix(base)
-    color(inspected, :number, opts)
+  def inspect(thing, %Inspect.Opts{base: base}) do
+    Integer.to_string(thing, base_to_value(base))
+    |> prepend_prefix(base)
   end
 
   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
 
 defimpl Inspect, for: Float do
-  def inspect(term, opts) do
-    inspected = IO.iodata_to_binary(:io_lib_format.fwrite_g(term))
-    color(inspected, :number, opts)
+  def inspect(thing, _opts) do
+    IO.iodata_to_binary(:io_lib_format.fwrite_g(thing))
   end
 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])
-    color(source, :regex, opts)
+  def inspect(regex, _opts) do
+    delim = ?/
+    concat ["~r",
+            <<delim, escape(regex.source, delim)::binary, delim>>,
+            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?" impl
+  # minus characters treated specially by regex: \s, \d, \b, \e
+
+  defp escape(<<?\n>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?n>>, term)
+
+  defp escape(<<?\r>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?r>>, term)
+
+  defp escape(<<?\t>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?t>>, term)
+
+  defp escape(<<?\v>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?v>>, term)
+
+  defp escape(<<?\f>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?f>>, term)
+
+  defp escape(<<?\a>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, ?\\, ?a>>, term)
+
+  defp escape(<<c::utf8>> <> rest, buf, term) do
+    charstr = <<c::utf8>>
+    if String.printable?(charstr) and not c in [?\d, ?\b, ?\e] do
+      escape(rest, buf <> charstr, term)
+    else
+      escape(rest, buf <> Inspect.BitString.escape_char(c), term)
+    end
+  end
+
+  defp escape(<<c>> <> rest, buf, term),
+    do: escape(rest, <<buf::binary, Inspect.BitString.escape_char(c)>>, 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_char_list(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 +477,16 @@ 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
 
@@ -397,7 +498,7 @@ end
 
 defimpl Inspect, for: Port do
   def inspect(port, _opts) do
-    IO.iodata_to_binary(:erlang.port_to_list(port))
+    IO.iodata_to_binary :erlang.port_to_list(port)
   end
 end
 
@@ -409,82 +510,19 @@ 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))
+          Inspect.Map.inspect(pruned, Inspect.Atom.inspect(struct, 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

@@ -1,49 +1,33 @@
 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
 
   @doc """
-  Determines if `integer` is odd.
+  Determines if an integer is odd.
 
-  Returns `true` if the given `integer` is an odd number,
-  otherwise it returns `false`.
+  Returns `true` if `n` is an odd number, otherwise `false`.
 
   Allowed in guard clauses.
 
   ## Examples
 
-      iex> Integer.is_odd(5)
+      iex> Integer.is_odd(3)
       true
 
-      iex> Integer.is_odd(6)
+      iex> Integer.is_odd(4)
       false
-
-      iex> Integer.is_odd(-5)
-      true
-
-      iex> Integer.is_odd(0)
-      false
-
   """
-  defguard is_odd(integer) when is_integer(integer) and (integer &&& 1) == 1
+  defmacro is_odd(n) do
+    quote do: (unquote(n) &&& 1) == 1
+  end
 
   @doc """
-  Determines if an `integer` is even.
+  Determines if an integer is even.
 
-  Returns `true` if the given `integer` is an even number,
-  otherwise it returns `false`.
+  Returns `true` if `n` is an even number, otherwise `false`.
 
   Allowed in guard clauses.
 
@@ -54,194 +38,72 @@ defmodule Integer do
 
       iex> Integer.is_even(5)
       false
-
-      iex> Integer.is_even(-10)
-      true
-
-      iex> Integer.is_even(0)
-      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(n) do
+    quote do: (unquote(n) &&& 1) == 0
   end
 
   @doc """
-  Computes the modulo remainder of an integer division.
+  Returns the ordered digits for the given non-negative integer.
 
-  This function performs a [floored division](`floor_div/2`), which means that
-  the result will always have the sign of the `divisor`.
-
-  Raises an `ArithmeticError` exception if one of the arguments is not an
-  integer, or when the `divisor` is `0`.
+  An optional base value may be provided representing the radix for the returned
+  digits.
 
   ## Examples
 
-      iex> Integer.mod(5, 2)
-      1
-      iex> Integer.mod(6, -4)
-      -2
+      iex> Integer.digits(101)
+      [1, 0, 1]
+
+      iex> Integer.digits(58127, 2)
+      [1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1]
 
   """
-  @doc since: "1.4.0"
-  @spec mod(integer, neg_integer | pos_integer) :: integer
-  def mod(dividend, divisor) do
-    remainder = rem(dividend, divisor)
+  @spec digits(non_neg_integer, pos_integer) :: [non_neg_integer]
+  def digits(n, base \\ 10) when is_integer(n)    and n >= 0
+                            and  is_integer(base) and base >= 2 do
+    do_digits(n, base, [])
+  end
 
-    if remainder * divisor < 0 do
-      remainder + divisor
-    else
-      remainder
-    end
+  defp do_digits(0, _base, []),  do: [0]
+  defp do_digits(0, _base, acc), do: acc
+  defp do_digits(n, base, acc)  do
+    do_digits div(n, base), base, [rem(n, base) | acc]
   end
 
   @doc """
-  Performs a floored integer division.
+  Returns the integer represented by the ordered digits.
 
-  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.
-
-  If you want to perform truncated integer division (rounding towards zero),
-  use `Kernel.div/2` instead.
+  An optional base value may be provided representing the radix for the digits.
 
   ## Examples
 
-      iex> Integer.floor_div(5, 2)
-      2
-      iex> Integer.floor_div(6, -4)
-      -2
-      iex> Integer.floor_div(-99, 2)
-      -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
-      div(dividend, divisor) - 1
-    else
-      div(dividend, divisor)
-    end
-  end
-
-  @doc """
-  Returns the ordered digits for the given `integer`.
-
-  An optional `base` value may be provided representing the radix for the returned
-  digits. This one must be an integer >= 2.
-
-  ## Examples
-
-      iex> Integer.digits(123)
-      [1, 2, 3]
-
-      iex> Integer.digits(170, 2)
-      [1, 0, 1, 0, 1, 0, 1, 0]
-
-      iex> Integer.digits(-170, 2)
-      [-1, 0, -1, 0, -1, 0, -1, 0]
-
-  """
-  @spec digits(integer, pos_integer) :: [integer, ...]
-  def digits(integer, base \\ 10)
-      when is_integer(integer) and is_integer(base) and base >= 2 do
-    do_digits(integer, base, [])
-  end
-
-  defp do_digits(integer, base, acc) when abs(integer) < base, do: [integer | acc]
-
-  defp do_digits(integer, base, acc),
-    do: do_digits(div(integer, base), base, [rem(integer, base) | acc])
-
-  @doc """
-  Returns the integer represented by the ordered `digits`.
-
-  An optional `base` value may be provided representing the radix for the `digits`.
-  Base has to be an integer greater than or equal to `2`.
-
-  ## Examples
-
-      iex> Integer.undigits([1, 2, 3])
-      123
+      iex> Integer.undigits([1, 0, 1])
+      101
 
       iex> Integer.undigits([1, 4], 16)
       20
-
-      iex> Integer.undigits([])
-      0
-
   """
-  @spec undigits([integer], pos_integer) :: integer
-  def undigits(digits, base \\ 10) when is_list(digits) and is_integer(base) and base >= 2 do
+  @spec undigits([integer], integer) :: integer
+  def undigits(digits, base \\ 10) when is_integer(base) do
     do_undigits(digits, base, 0)
   end
 
   defp do_undigits([], _base, acc), do: acc
-
-  defp do_undigits([digit | _], base, _) when is_integer(digit) and digit >= base,
-    do: raise(ArgumentError, "invalid digit #{digit} in base #{base}")
-
-  defp do_undigits([digit | tail], base, acc) when is_integer(digit),
-    do: do_undigits(tail, base, acc * base + digit)
+  defp do_undigits([digit | tail], base, acc) do
+    do_undigits(tail, base, acc * base + digit)
+  end
 
   @doc """
-  Parses a text representation of an integer.
+  Converts a binary from a text representation of an integer
+  in an optional base `base` to the corresponding integer.
 
-  An optional `base` to the corresponding integer can be provided.
-  If `base` is not given, 10 will be used.
+  If the base `base` is not given, base 10 will be used.
 
-  If successful, returns a tuple in the form of `{integer, remainder_of_binary}`.
+  If successful, returns a tuple of the form `{integer, remainder_of_binary}`.
   Otherwise `:error`.
 
   Raises an error if `base` is less than 2 or more than 36.
 
-  If you want to convert a string-formatted integer directly to an integer,
-  `String.to_integer/1` or `String.to_integer/2` can be used instead.
-
   ## Examples
 
       iex> Integer.parse("34")
@@ -269,55 +131,73 @@ 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(binary, base) when is_integer(base) 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
+  def parse(_, base) do
+    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
+      :error -> :error
+      {number, remainder} -> {-number, remainder}
     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(bin, base) when is_binary(bin) do
+    do_parse(bin, 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, base))
+    else
+      :error
     end
   end
 
-  defp count_digits(<<rest::bits>>, base) do
-    count_digits_nosign(rest, base, 0)
-  end
+  defp do_parse(_, _), do: :error
 
-  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, base))
+    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 `some_integer`.
 
   Inlined by the compiler.
 
@@ -326,164 +206,59 @@ defmodule Integer do
       iex> Integer.to_string(123)
       "123"
 
-      iex> Integer.to_string(+456)
-      "456"
-
-      iex> Integer.to_string(-789)
-      "-789"
-
-      iex> Integer.to_string(0123)
-      "123"
-
-      iex> Integer.to_string(100, 16)
-      "64"
-
-      iex> Integer.to_string(-100, 16)
-      "-64"
-
-      iex> Integer.to_string(882_681_651, 36)
-      "ELIXIR"
-
   """
-  @spec to_string(integer, 2..36) :: String.t()
-  def to_string(integer, base \\ 10) do
-    :erlang.integer_to_binary(integer, base)
+  @spec to_string(integer) :: String.t
+  def to_string(some_integer) do
+    :erlang.integer_to_binary(some_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. If no `base` is given,
-  it defaults to `10`.
+  Returns a binary which corresponds to the text representation
+  of `some_integer` in base `base`.
 
   Inlined by the compiler.
 
   ## Examples
 
-      iex> Integer.to_charlist(123)
-      '123'
-
-      iex> Integer.to_charlist(+456)
-      '456'
-
-      iex> Integer.to_charlist(-789)
-      '-789'
-
-      iex> Integer.to_charlist(0123)
-      '123'
-
-      iex> Integer.to_charlist(100, 16)
-      '64'
-
-      iex> Integer.to_charlist(-100, 16)
-      '-64'
-
-      iex> Integer.to_charlist(882_681_651, 36)
-      'ELIXIR'
+      iex> Integer.to_string(100, 16)
+      "64"
 
   """
-  @spec to_charlist(integer, 2..36) :: charlist
-  def to_charlist(integer, base \\ 10) do
-    :erlang.integer_to_list(integer, base)
+  @spec to_string(integer, 2..36) :: String.t
+  def to_string(some_integer, base) do
+    :erlang.integer_to_binary(some_integer, base)
   end
 
   @doc """
-  Returns the greatest common divisor of the two given integers.
+  Returns a char list which corresponds to the text representation of the given integer.
 
-  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`.
+  Inlined by the compiler.
 
   ## 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
+      iex> Integer.to_char_list(7)
+      '7'
 
   """
-  @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))
+  @spec to_char_list(integer) :: char_list
+  def to_char_list(number) do
+    :erlang.integer_to_list(number)
   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.
+  Returns a char list which corresponds to the text representation of the
+  given integer in the given base.
 
-  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}`.
+  Inlined by the compiler.
 
   ## 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}
+      iex> Integer.to_char_list(1023, 16)
+      '3FF'
 
   """
-  @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)
+  @spec to_char_list(integer, 2..36) :: char_list
+  def to_char_list(number, base) do
+    :erlang.integer_to_list(number, base)
   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
-
-  @doc false
-  @deprecated "Use Integer.to_charlist/1 instead"
-  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

@@ -1,22 +1,25 @@
 defmodule IO do
-  @moduledoc ~S"""
-  Functions handling input/output (IO).
+  @moduledoc """
+  Functions handling IO.
 
   Many functions in this module expect an IO device as an argument.
-  An IO device must be a PID or an atom representing a process.
+  An IO device must be a pid or an atom representing a process.
   For convenience, Elixir provides `:stdio` and `:stderr` as
   shortcuts to Erlang's `:standard_io` and `:standard_error`.
 
-  The majority of the functions expect chardata. 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 char data, i.e. strings or
+  lists of characters and strings. In case another type is given,
+  functions will convert to string via the `String.Chars` protocol
+  (as shown in typespecs).
+
+  The functions starting with `bin*` expect iodata as an argument,
+  i.e. binaries or lists of bytes and binaries.
 
   ## IO devices
 
-  An IO device may be an atom or a PID. In case it is an atom,
+  An IO device may be an atom or a pid. In case it is an atom,
   the atom must be the name of a registered process. In addition,
-  Elixir provides two shortcuts:
+  Elixir provides two shorcuts:
 
     * `:stdio` - a shortcut for `:standard_io`, which maps to
       the current `Process.group_leader/0` in Erlang
@@ -24,441 +27,28 @@ 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)
+  import :erlang, only: [group_leader: 0]
 
-  @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`.
-
-  It returns:
-
-    * `data` - the output characters
-
-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
-
-  """
-  @spec read(device, :eof | :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)
-  end
-
-  def read(device, :line) do
-    :io.get_line(map_dev(device), '')
-  end
-
-  def read(device, count) when is_integer(count) and count >= 0 do
-    :io.get_chars(map_dev(device), '', count)
-  end
-
-  @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`.
-
-  It returns:
-
-    * `data` - the output bytes
-
-    * `:eof` - end of file was encountered
-
-    * `{:error, reason}` - other (rare) error condition;
-      for instance, `{:error, :estale}` if reading from an
-      NFS volume
-
-  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
-  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), "")
-  end
-
-  def binread(device, :line) do
-    case :file.read_line(map_dev(device)) do
-      {:ok, data} -> data
-      other -> other
-    end
-  end
-
-  def binread(device, count) when is_integer(count) and count >= 0 do
-    case :file.read(map_dev(device), count) do
-      {:ok, data} -> data
-      other -> other
-    end
-  end
-
-  @read_all_size 4096
-  defp binread_eof(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
-      other -> other
+  defmacrop is_iodata(data) do
+    quote do
+      is_list(unquote(data)) or is_binary(unquote(data))
     end
   end
 
   @doc """
-  Writes `chardata` to the given `device`.
-
-  By default, the `device` is the standard output.
-
-  ## Examples
-
-      IO.write("sample")
-      #=> sample
-
-      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))
-  end
-
-  @doc """
-  Writes `iodata` to the given `device`.
-
-  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.
-
-  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.
-  """
-  @spec binwrite(device, iodata) :: :ok | {:error, term}
-  def binwrite(device \\ :stdio, iodata) when is_iodata(iodata) do
-    :file.write(map_dev(device), iodata)
-  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])
-  end
-
-  @doc """
-  Writes a `message` to stderr, along with the given `stacktrace`.
-
-  This function also notifies the compiler a warning was printed
-  (in case --warnings-as-errors was enabled). It returns `:ok`
-  if it succeeds.
-
-  An empty list can be passed to avoid stacktrace printing.
-
-  ## Examples
-
-      stacktrace = [{MyApp, :main, 1, [file: 'my_app.ex', line: 4]}]
-      IO.warn("variable bar is unused", stacktrace)
-      #=> warning: variable bar is unused
-      #=>   my_app.ex:4: MyApp.main/1
-
-  """
-  @spec warn(chardata | String.Chars.t(), Exception.stacktrace()) :: :ok
-  def warn(message, []) do
-    message = [to_chardata(message), ?\n]
-    :elixir_errors.log_and_print_warning(0, nil, message, message)
-  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
-  end
-
-  @doc """
-  Writes a `message` to stderr, along with the current stacktrace.
-
-  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")
-      #=> warning: variable bar is unused
-      #=>   (iex) evaluator.ex:108: IEx.Evaluator.eval/4
-
-  """
-  @spec warn(chardata | String.Chars.t()) :: :ok
-  def warn(message) do
-    {:current_stacktrace, stacktrace} = Process.info(self(), :current_stacktrace)
-    warn(message, Enum.drop(stacktrace, 2))
-  end
-
-  @doc """
-  Inspects and writes the given `item` to the device.
-
-  It's important to note that it returns the given `item` unchanged.
-  This makes it possible to "spy" on values by inserting an
-  `IO.inspect/2` call almost anywhere in your code, for example,
-  in the middle of a pipeline.
-
-  It enables pretty printing by default with width of
-  80 characters. The width can be changed by explicitly
-  passing the `:width` option.
-
-  The output can be decorated with a label, by providing the `:label`
-  option to easily distinguish it from other `IO.inspect/2` calls.
-  The label will be printed before the inspected `item`.
-
-  See `Inspect.Opts` for a full list of remaining formatting options.
-
-  ## Examples
-
-      IO.inspect(<<0, 1, 2>>, width: 40)
-
-  Prints:
-
-      <<0, 1, 2>>
-
-  We can use the `:label` option to decorate the output:
-
-      IO.inspect(1..100, label: "a wonderful range")
-
-  Prints:
-
-      a wonderful range: 1..100
-
-  The `:label` option is especially useful with pipelines:
-
-      [1, 2, 3]
-      |> IO.inspect(label: "before")
-      |> Enum.map(&(&1 * 2))
-      |> IO.inspect(label: "after")
-      |> Enum.sum()
-
-  Prints:
-
-      before: [1, 2, 3]
-      after: [2, 4, 6]
-
-  """
-  @spec inspect(item, keyword) :: item when item: var
-  def inspect(item, opts \\ []) do
-    inspect(:stdio, item, opts)
-  end
-
-  @doc """
-  Inspects `item` according to the given options using the IO `device`.
-
-  See `inspect/2` for a full list of options.
-  """
-  @spec inspect(device, item, keyword) :: 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])
-    item
-  end
-
-  @doc """
-  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.
-  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
-
-  def getn(prompt, count) when is_integer(count) and count > 0 do
-    getn(:stdio, prompt, count)
-  end
-
-  def getn(device, prompt) when not is_integer(prompt) do
-    getn(device, prompt, 1)
-  end
-
-  @doc """
-  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.
-  Otherwise, `count` is the number of raw bytes to be retrieved.
+  Reads `count` characters from the IO device, a whole
+  `:line` or the whole device with `:all`.
 
   It returns:
 
@@ -470,30 +60,199 @@ 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 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), [])
+  @spec read(device, :all | :line | non_neg_integer) :: chardata | nodata
+  def read(device \\ group_leader, chars_or_line)
+
+  def read(device, :all) do
+    do_read_all(map_dev(device), "")
   end
 
-  def getn(device, prompt, count) when is_integer(count) and count > 0 do
-    :io.get_chars(map_dev(device), to_chardata(prompt), count)
+  def read(device, :line) do
+    :io.get_line(map_dev(device), '')
   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))
+  def read(device, count) when count >= 0 do
+    :io.get_chars(map_dev(device), '', count)
+  end
+
+  defp do_read_all(mapped_dev, acc) do
+    case :io.get_line(mapped_dev, "") do
+      line when is_binary(line) -> do_read_all(mapped_dev, acc <> line)
+      :eof -> acc
       other -> other
     end
   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 """
+  Reads `count` characters from the IO device, a whole
+  `:line` or the whole device with `:all`.
 
-  @doc ~S"""
-  Reads a line from the IO `device`.
+  It returns:
+
+    * `data` - the input characters
+
+    * `:eof` - end of file was encountered
+
+    * `{:error, reason}` - other (rare) error condition;
+      for instance, `{:error, :estale}` if reading from an
+      NFS volume
+
+  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, :all | :line | non_neg_integer) :: iodata | nodata
+  def binread(device \\ group_leader, chars_or_line)
+
+  def binread(device, :all) do
+    do_binread_all(map_dev(device), "")
+  end
+
+  def binread(device, :line) do
+    case :file.read_line(map_dev(device)) do
+      {:ok, data} -> data
+      other -> other
+    end
+  end
+
+  def binread(device, count) when count >= 0 do
+    case :file.read(map_dev(device), count) do
+      {:ok, data} -> data
+      other -> other
+    end
+  end
+
+  @read_all_size 4096
+  defp do_binread_all(mapped_dev, acc) do
+    case :file.read(mapped_dev, @read_all_size) do
+      {:ok, data} -> do_binread_all(mapped_dev, acc <> data)
+      :eof -> acc
+      other -> other
+    end
+  end
+
+  @doc """
+  Writes the given argument to the given device.
+
+  By default the device is the standard output.
+  It returns `:ok` if it succeeds.
+
+  ## Examples
+
+      IO.write "sample"
+      #=> "sample"
+
+      IO.write :stderr, "error"
+      #=> "error"
+
+  """
+  @spec write(device, chardata | String.Chars.t) :: :ok
+  def write(device \\ group_leader(), item) do
+    :io.put_chars map_dev(device), to_chardata(item)
+  end
+
+  @doc """
+  Writes the given argument to the given device
+  as a binary, no unicode conversion happens.
+
+  Check `write/2` for more information.
+
+  Note: do not use this function on IO devices in unicode mode
+  as it will return the wrong result.
+  """
+  @spec binwrite(device, iodata) :: :ok | {:error, term}
+  def binwrite(device \\ group_leader(), item) when is_iodata(item) do
+    :file.write map_dev(device), item
+  end
+
+  @doc """
+  Writes the argument to the device, similar to `write/2`,
+  but adds a newline at the end. The argument is expected
+  to be a chardata.
+  """
+  @spec puts(device, chardata | String.Chars.t) :: :ok
+  def puts(device \\ group_leader(), item) do
+    erl_dev = map_dev(device)
+    :io.put_chars erl_dev, [to_chardata(item), ?\n]
+  end
+
+  @doc """
+  Inspects and writes the given argument to the device.
+
+  It enables pretty printing by default with width of
+  80 characters. The width can be changed by explicitly
+  passing the `:width` option.
+
+  See `Inspect.Opts` for a full list of options.
+
+  ## Examples
+
+      IO.inspect Process.list, width: 40
+
+  """
+  @spec inspect(item, Keyword.t) :: item when item: var
+  def inspect(item, opts \\ []) do
+    inspect group_leader(), item, opts
+  end
+
+  @doc """
+  Inspects the item with options using the given device.
+
+  See `Inspect.Opts` for a full list of options.
+  """
+  @spec inspect(device, item, Keyword.t) :: item when item: var
+  def inspect(device, item, opts) when is_list(opts) do
+    opts   = struct(Inspect.Opts, opts)
+    iodata = Inspect.Algebra.format(Inspect.Algebra.to_doc(item, opts), opts.width)
+    puts device, iodata
+    item
+  end
+
+  @doc """
+  Gets a number of bytes from the io device. If the
+  io device is a unicode device, `count` implies
+  the number of unicode codepoints to be retrieved.
+  Otherwise, `count` is the number of raw bytes to be retrieved.
+  It returns:
+
+    * `data` - the input characters
+
+    * `:eof` - end of file was encountered
+
+    * `{:error, reason}` - other (rare) error condition;
+      for instance, `{:error, :estale}` if reading from an
+      NFS volume
+  """
+  @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) do
+    getn(group_leader, prompt, count)
+  end
+
+  def getn(device, prompt) do
+    getn(device, prompt, 1)
+  end
+
+  @doc """
+  Gets a number of bytes from the io device. If the
+  io device is a unicode device, `count` implies
+  the number of unicode codepoints to be retrieved.
+  Otherwise, `count` is the number of raw bytes to be retrieved.
+  """
+  @spec getn(device, chardata | String.Chars.t, pos_integer) :: chardata | nodata
+  def getn(device, prompt, count) do
+    :io.get_chars(map_dev(device), to_chardata(prompt), count)
+  end
+
+  @doc """
+  Reads a line from the IO device.
 
   It returns:
 
@@ -510,104 +269,69 @@ 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?"
   """
-  @spec gets(device, chardata | String.Chars.t()) :: chardata | nodata
-  def gets(device \\ :stdio, prompt) do
+  @spec gets(device, chardata | String.Chars.t) :: chardata | nodata
+  def gets(device \\ group_leader(), 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`.
+  Converts the io device into a `IO.Stream`.
 
   An `IO.Stream` implements both `Enumerable` and
   `Collectable`, allowing it to be used for both read
   and write.
 
-  The `device` is iterated by the given number of characters or line by line if
-  `:line` is given.
+  The device is iterated line by line if `:line` is given or
+  by a given number of codepoints.
 
-  This reads from the IO as UTF-8. Check out
+  This reads the IO as utf-8. Check out
   `IO.binstream/2` to handle the IO as a raw binary.
 
   Note that an IO stream has side effects and every time
   you go over the stream you may get different results.
 
-  `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)
-      when line_or_codepoints == :line
-      when is_integer(line_or_codepoints) and line_or_codepoints > 0 do
+  @spec stream(device, :line | pos_integer) :: Enumerable.t
+  def stream(device, line_or_codepoints) 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.
+  Converts the IO device into a `IO.Stream`.
 
   An `IO.Stream` implements both `Enumerable` and
   `Collectable`, allowing it to be used for both read
   and write.
 
-  The `device` is iterated by the given number of bytes or line by line if
-  `:line` is given. This reads from the IO device as a raw binary.
+  The device is iterated line by line or by a number of bytes.
+  This reads the IO device as a raw binary.
 
   Note that an IO stream has side effects and every time
   you go over the stream you may get different results.
 
-  Finally, do not use this function on IO devices in Unicode
+  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)
-      when line_or_bytes == :line
-      when is_integer(line_or_bytes) and line_or_bytes > 0 do
+  @spec binstream(device, :line | pos_integer) :: Enumerable.t
+  def binstream(device, line_or_bytes) do
     IO.Stream.__build__(map_dev(device), true, line_or_bytes)
   end
 
   @doc """
-  Converts chardata into a string.
+  Converts chardata (a list of integers representing codepoints,
+  lists and strings) into a string.
 
-  For more information about chardata, see the ["Chardata"](#module-chardata)
-  section in the module documentation.
-
-  In case the conversion fails, it raises an `UnicodeConversionError`.
-  If a string is given, it returns the string itself.
+  In case the conversion fails, it raises a `UnicodeConversionError`.
+  If a string is given, returns the string itself.
 
   ## Examples
 
@@ -617,32 +341,33 @@ defmodule IO do
       iex> IO.chardata_to_string([0x0061, "bc"])
       "abc"
 
-      iex> IO.chardata_to_string("string")
-      "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
 
   def chardata_to_string(list) when is_list(list) do
-    List.to_string(list)
+    case :unicode.characters_to_binary(list) do
+      result when is_binary(result) ->
+        result
+
+      {:error, encoded, rest} ->
+        raise UnicodeConversionError, encoded: encoded, rest: rest, kind: :invalid
+
+      {:incomplete, encoded, rest} ->
+        raise UnicodeConversionError, encoded: encoded, rest: rest, kind: :incomplete
+    end
   end
 
   @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 char list to a string (UTF-8 encoded), please
+  use `chardata_to_string/1` instead.
 
   If this function receives a binary, the same binary is returned.
 
@@ -653,7 +378,7 @@ defmodule IO do
       iex> bin1 = <<1, 2, 3>>
       iex> bin2 = <<4, 5>>
       iex> bin3 = <<6>>
-      iex> IO.iodata_to_binary([bin1, 1, [2, 3, bin2], 4 | bin3])
+      iex> IO.iodata_to_binary([bin1, 1, [2, 3, bin2], 4|bin3])
       <<1, 2, 3, 1, 2, 3, 4, 5, 4, 6>>
 
       iex> bin = <<1, 2, 3>>
@@ -662,52 +387,45 @@ 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.
 
   ## Examples
 
-      iex> IO.iodata_length([1, 2 | <<3, 4>>])
+      iex> IO.iodata_length([1, 2|<<3, 4>>])
       4
 
   """
   @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
-  def each_stream(device, line_or_codepoints) do
-    case read(device, line_or_codepoints) do
+  def each_stream(device, what) do
+    case read(device, what) do
       :eof ->
         {:halt, device}
-
       {:error, reason} ->
         raise IO.StreamError, reason: reason
-
       data ->
         {[data], device}
     end
   end
 
   @doc false
-  def each_binstream(device, line_or_chars) do
-    case binread(device, line_or_chars) do
+  def each_binstream(device, what) do
+    case binread(device, what) do
       :eof ->
         {:halt, device}
-
       {:error, reason} ->
         raise IO.StreamError, reason: reason
-
       data ->
         {[data], device}
     end
@@ -715,8 +433,8 @@ 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
+  # Map the Elixir names for standard io and error to Erlang names
+  defp map_dev(:stdio),  do: :standard_io
   defp map_dev(:stderr), do: :standard_error
   defp map_dev(other) when is_atom(other) or is_pid(other) or is_tuple(other), do: other
 

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.
@@ -68,8 +42,8 @@ defmodule IO.ANSI do
     Application.get_env(:elixir, :ansi_enabled, false)
   end
 
-  @doc "Sets foreground color."
-  @spec color(0..255) :: String.t()
+  @doc "Sets foreground color"
+  @spec color(0..255) :: String.t
   def color(code) when code in 0..255, do: "\e[38;5;#{code}m"
 
   @doc ~S"""
@@ -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()
+  @doc "Sets background color"
+  @spec color_background(0..255) :: String.t
   def color_background(code) when code in 0..255, do: "\e[48;5;#{code}m"
 
   @doc ~S"""
@@ -91,145 +65,106 @@ 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)
+  @doc "Resets all attributes"
+  defsequence :reset, 0
 
-  @doc "Bright (increased intensity) or bold."
-  defsequence(:bright, 1)
+  @doc "Bright (increased intensity) or Bold"
+  defsequence :bright, 1
 
-  @doc "Faint (decreased intensity). Not widely supported."
-  defsequence(:faint, 2)
+  @doc "Faint (decreased intensity), not widely supported"
+  defsequence :faint, 2
 
-  @doc "Italic: on. Not widely supported. Sometimes treated as inverse."
-  defsequence(:italic, 3)
+  @doc "Italic: on. Not widely supported. Sometimes treated as inverse"
+  defsequence :italic, 3
 
-  @doc "Underline: single."
-  defsequence(:underline, 4)
+  @doc "Underline: Single"
+  defsequence :underline, 4
 
-  @doc "Blink: slow. Less than 150 per minute."
-  defsequence(:blink_slow, 5)
+  @doc "Blink: Slow. Less than 150 per minute"
+  defsequence :blink_slow, 5
 
-  @doc "Blink: rapid. MS-DOS ANSI.SYS; 150 per minute or more; not widely supported."
-  defsequence(:blink_rapid, 6)
+  @doc "Blink: Rapid. MS-DOS ANSI.SYS; 150 per minute or more; not widely supported"
+  defsequence :blink_rapid, 6
 
-  @doc "Image: negative. Swap foreground and background."
-  defsequence(:inverse, 7)
+  @doc "Image: Negative. Swap foreground and background"
+  defsequence :inverse, 7
 
-  @doc "Image: negative. Swap foreground and background."
-  defsequence(:reverse, 7)
+  @doc "Image: Negative. Swap foreground and background"
+  defsequence :reverse, 7
 
-  @doc "Conceal. Not widely supported."
-  defsequence(:conceal, 8)
+  @doc "Conceal. Not widely supported"
+  defsequence :conceal, 8
 
-  @doc "Crossed-out. Characters legible, but marked for deletion. Not widely supported."
-  defsequence(:crossed_out, 9)
+  @doc "Crossed-out. Characters legible, but marked for deletion. Not widely supported"
+  defsequence :crossed_out, 9
 
-  @doc "Sets primary (default) font."
-  defsequence(:primary_font, 10)
+  @doc "Sets primary (default) font"
+  defsequence :primary_font, 10
 
   for font_n <- [1, 2, 3, 4, 5, 6, 7, 8, 9] do
-    @doc "Sets alternative font #{font_n}."
-    defsequence(:"font_#{font_n}", font_n + 10)
+    @doc "Sets alternative font #{font_n}"
+    defsequence :"font_#{font_n}", font_n + 10
   end
 
-  @doc "Normal color or intensity."
-  defsequence(:normal, 22)
+  @doc "Normal color or intensity"
+  defsequence :normal, 22
 
-  @doc "Not italic."
-  defsequence(:not_italic, 23)
+  @doc "Not italic"
+  defsequence :not_italic, 23
 
-  @doc "Underline: none."
-  defsequence(:no_underline, 24)
+  @doc "Underline: None"
+  defsequence :no_underline, 24
 
-  @doc "Blink: off."
-  defsequence(:blink_off, 25)
-
-  @doc "Image: positive. Normal foreground and background."
-  defsequence(:inverse_off, 27)
-
-  @doc "Image: positive. Normal foreground and background."
-  defsequence(:reverse_off, 27)
+  @doc "Blink: off"
+  defsequence :blink_off, 25
 
   colors = [:black, :red, :green, :yellow, :blue, :magenta, :cyan, :white]
 
   for {color, code} <- Enum.with_index(colors) do
-    @doc "Sets foreground color to #{color}."
-    defsequence(color, code + 30)
+    @doc "Sets foreground color to #{color}"
+    defsequence color, code + 30
 
-    @doc "Sets foreground color to light #{color}."
-    defsequence(:"light_#{color}", code + 90)
-
-    @doc "Sets background color to #{color}."
-    defsequence(:"#{color}_background", code + 40)
-
-    @doc "Sets background color to light #{color}."
-    defsequence(:"light_#{color}_background", code + 100)
+    @doc "Sets background color to #{color}"
+    defsequence :"#{color}_background", code + 40
   end
 
-  @doc "Default text color."
-  defsequence(:default_color, 39)
+  @doc "Default text color"
+  defsequence :default_color, 39
 
-  @doc "Default background color."
-  defsequence(:default_background, 49)
+  @doc "Default background color"
+  defsequence :default_background, 49
 
-  @doc "Framed."
-  defsequence(:framed, 51)
+  @doc "Framed"
+  defsequence :framed, 51
 
-  @doc "Encircled."
-  defsequence(:encircled, 52)
+  @doc "Encircled"
+  defsequence :encircled, 52
 
-  @doc "Overlined."
-  defsequence(:overlined, 53)
+  @doc "Overlined"
+  defsequence :overlined, 53
 
-  @doc "Not framed or encircled."
-  defsequence(:not_framed_encircled, 54)
+  @doc "Not framed or encircled"
+  defsequence :not_framed_encircled, 54
 
-  @doc "Not overlined."
-  defsequence(:not_overlined, 55)
+  @doc "Not overlined"
+  defsequence :not_overlined, 55
 
-  @doc "Sends cursor home."
-  defsequence(:home, "", "H")
+  @doc "Sends cursor home"
+  defsequence :home, "", "H"
 
-  @doc """
-  Sends cursor to the absolute position specified by `line` and `column`.
+  @doc "Clears screen"
+  defsequence :clear, "2", "J"
 
-  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"
-
-  @doc "Clears screen."
-  defsequence(:clear, "2", "J")
-
-  @doc "Clears line."
-  defsequence(:clear_line, "2", "K")
+  @doc "Clears line"
+  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 +177,7 @@ 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
@@ -251,8 +186,8 @@ defmodule IO.ANSI do
       [[[[[[], "Hello, "] | "\e[31m"] | "\e[1m"], "world!"] | "\e[0m"]
 
   """
-  def format(chardata, emit? \\ enabled?()) when is_boolean(emit?) do
-    do_format(chardata, [], [], emit?, :maybe)
+  def format(chardata, emit \\ enabled?) when is_boolean(emit) do
+    do_format(chardata, [], [], emit, :maybe)
   end
 
   @doc ~S"""
@@ -262,7 +197,7 @@ 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
@@ -271,12 +206,12 @@ defmodule IO.ANSI do
       [[[[[[] | "\e[1m"], 87], 111], 114], 100]
 
   """
-  def format_fragment(chardata, emit? \\ enabled?()) when is_boolean(emit?) do
-    do_format(chardata, [], [], emit?, false)
+  def format_fragment(chardata, emit \\ enabled?) when is_boolean(emit) do
+    do_format(chardata, [], [], emit, false)
   end
 
-  defp do_format([term | rest], rem, acc, emit?, append_reset) do
-    do_format(term, [rest | rem], acc, emit?, append_reset)
+  defp do_format([term | rest], rem, acc, emit, append_reset) do
+    do_format(term, [rest | rem], acc, emit, append_reset)
   end
 
   defp do_format(term, rem, acc, true, append_reset) when is_atom(term) do
@@ -287,19 +222,19 @@ defmodule IO.ANSI do
     do_format([], rem, acc, false, append_reset)
   end
 
-  defp do_format(term, rem, acc, emit?, append_reset) when not is_list(term) do
-    do_format([], rem, [acc, term], emit?, append_reset)
+  defp do_format(term, rem, acc, emit, append_reset) when not is_list(term) do
+    do_format([], rem, [acc | [term]], emit, append_reset)
   end
 
-  defp do_format([], [next | rest], acc, emit?, append_reset) do
-    do_format(next, rest, acc, emit?, append_reset)
+  defp do_format([], [next | rest], acc, emit, append_reset) do
+    do_format(next, rest, acc, emit, append_reset)
   end
 
   defp do_format([], [], acc, true, true) do
-    [acc | IO.ANSI.reset()]
+    [acc | IO.ANSI.reset]
   end
 
-  defp do_format([], [], acc, _emit?, _append_reset) do
+  defp do_format([], [], acc, _emit, _append_reset) do
     acc
   end
 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
@@ -17,10 +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
-
-  It is worth noting that an IO stream has side effects and every time you go
-  over the stream you may get different results.
+    * `line_or_bytes` - if reading should read lines or a given amount of bytes
 
   """
 
@@ -42,12 +38,10 @@ 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 +50,10 @@ 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 +63,5 @@ 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}
@@ -163,53 +111,32 @@ defmodule Kernel.CLI do
 
   defp shared_option?(list, config, callback) do
     case parse_shared(list, config) do
-      {[h | hs], _} when h == hd(list) ->
+      {[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)
+  @elixir_internals [:elixir, :elixir_exp, :elixir_compiler, :elixir_module, :elixir_clauses,
+                     :elixir_translator, :elixir_expand, :elixir_lexical, :elixir_exp_clauses,
+                     :elixir_def]
 
-  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]
-
-  defp prune_stacktrace([{mod, _, _, _} | t]) when mod in @elixir_internals do
+  defp prune_stacktrace([{mod, _, _, _}|t]) when mod in @elixir_internals do
     prune_stacktrace(t)
   end
 
-  defp prune_stacktrace([{__MODULE__, :wrapper, 1, _} | _]) do
+  defp prune_stacktrace([{__MODULE__, :wrapper, 1, _}|_]) do
     []
   end
 
-  defp prune_stacktrace([h | t]) do
-    [h | prune_stacktrace(t)]
+  defp prune_stacktrace([h|t]) do
+    [h|prune_stacktrace(t)]
   end
 
   defp prune_stacktrace([]) do
@@ -218,108 +145,98 @@ defmodule Kernel.CLI do
 
   # Parse shared options
 
-  defp parse_shared([opt | _], _config) when opt in @standalone_opts do
-    IO.puts(:stderr, "#{opt} : Standalone options can't be combined with other options")
-    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.version}"
     else
-      IO.puts(:erlang.system_info(:system_version))
-      IO.puts("Elixir " <> System.build_info()[:build])
+      IO.puts :erlang.system_info(:system_version)
+      {:ok, v} = Version.parse(System.version)
+
+      case v.pre do
+        [] -> IO.puts "Elixir #{System.version}"
+        _  -> IO.puts "Elixir #{System.version} (#{System.build_info().revision})"
+      end
     end
 
-    parse_shared(t, config)
+    System.halt 0
   end
 
-  defp parse_shared(["-pa", h | t], config) do
+  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
+  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]})
+  defp parse_shared(["--app", h|t], config) do
+    parse_shared t, %{config | commands: [{:app, h} | config.commands]}
   end
 
-  defp parse_shared(["--no-halt" | t], config) do
-    parse_shared(t, %{config | no_halt: true})
+  defp parse_shared(["--no-halt"|t], config) do
+    parse_shared t, %{config | halt: false}
   end
 
-  defp parse_shared(["-e", h | t], config) do
-    parse_shared(t, %{config | commands: [{:eval, h} | config.commands]})
+  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]})
+  defp parse_shared(["-r", h|t], config) do
+    parse_shared t, %{config | commands: [{:require, 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]})
+  defp parse_shared(["-pr", h|t], config) do
+    parse_shared t, %{config | commands: [{:parallel_require, h} | config.commands]}
   end
 
-  defp parse_shared(["-r", h | t], config) do
-    parse_shared(t, %{config | commands: [{:require, h} | config.commands]})
+  defp parse_shared([erl, _|t], config) when erl in ["--erl", "--sname", "--name", "--cookie"] do
+    parse_shared t, config
   end
 
-  defp parse_shared(["-pr", h | t], config) do
-    parse_shared(t, %{config | commands: [{:parallel_require, h} | config.commands]})
+  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)]
-      list -> Enum.map(list, &to_charlist/1)
+      []   -> [to_char_list(path)]
+      list -> Enum.map(list, &to_char_list/1)
     end
   end
 
   # Process init options
 
-  defp parse_argv(["--" | t], config) do
+  defp parse_argv(["--"|t], config) do
     {config, t}
   end
 
-  defp parse_argv(["+elixirc" | t], config) do
-    parse_compiler(t, config)
+  defp parse_argv(["+elixirc"|t], config) do
+    parse_compiler t, config
   end
 
-  defp parse_argv(["+iex" | t], config) do
-    parse_iex(t, config)
+  defp parse_argv(["+iex"|t], config) do
+    parse_iex t, config
   end
 
-  defp parse_argv(["-S", h | t], config) do
+  defp parse_argv(["-S", h|t], config) do
     {%{config | commands: [{:script, h} | config.commands]}, t}
   end
 
-  defp parse_argv([h | t] = list, config) 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}
@@ -333,82 +250,74 @@ defmodule Kernel.CLI do
 
   # Parse compiler options
 
-  defp parse_compiler(["--" | t], config) do
+  defp parse_compiler(["--"|t], config) do
     {config, t}
   end
 
-  defp parse_compiler(["-o", h | t], config) do
-    parse_compiler(t, %{config | output: h})
+  defp parse_compiler(["-o", h|t], config) do
+    parse_compiler t, %{config | output: h}
   end
 
-  defp parse_compiler(["--no-docs" | t], config) do
-    parse_compiler(t, %{config | compiler_options: [{:docs, false} | config.compiler_options]})
+  defp parse_compiler(["--no-docs"|t], config) do
+    parse_compiler t, %{config | compiler_options: [{:docs, false} | config.compiler_options]}
   end
 
-  defp parse_compiler(["--no-debug-info" | t], config) do
-    compiler_options = [{:debug_info, false} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+  defp parse_compiler(["--no-debug-info"|t], config) do
+    parse_compiler t, %{config | compiler_options: [{:debug_info, false} | config.compiler_options]}
   end
 
-  defp parse_compiler(["--ignore-module-conflict" | t], config) do
-    compiler_options = [{:ignore_module_conflict, true} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+  defp parse_compiler(["--ignore-module-conflict"|t], config) do
+    parse_compiler t, %{config | compiler_options: [{:ignore_module_conflict, true} | config.compiler_options]}
   end
 
-  defp parse_compiler(["--warnings-as-errors" | t], config) do
-    compiler_options = [{:warnings_as_errors, true} | config.compiler_options]
-    parse_compiler(t, %{config | compiler_options: compiler_options})
+  defp parse_compiler(["--warnings-as-errors"|t], config) do
+    parse_compiler t, %{config | compiler_options: [{:warnings_as_errors, true} | config.compiler_options]}
   end
 
-  defp parse_compiler(["--verbose" | t], config) do
-    parse_compiler(t, %{config | verbose_compile: true})
+  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})
-  end
-
-  defp parse_compiler([h | t] = list, config) do
+  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
 
   defp parse_compiler([], config) do
-    {%{config | commands: [{:compile, config.compile} | config.commands]}, []}
+    {%{config | commands: [{:compile, config.compile}|config.commands]}, []}
   end
 
-  # Parse IEx options
+  # Parse iex options
 
-  defp parse_iex(["--" | t], config) do
+  defp parse_iex(["--"|t], config) do
     {config, t}
   end
 
   # This clause is here so that Kernel.CLI does not
   # error out with "unknown option"
-  defp parse_iex(["--dot-iex", _ | t], config) do
-    parse_iex(t, config)
+  defp parse_iex(["--dot-iex", _|t], config) do
+    parse_iex t, config
   end
 
-  defp parse_iex([opt, _ | t], config) when opt in ["--remsh"] do
-    parse_iex(t, config)
+  defp parse_iex([opt, _|t], config) when opt in ["--remsh"] do
+    parse_iex t, config
   end
 
-  defp parse_iex(["-S", h | t], config) do
+  defp parse_iex(["-S", h|t], config) do
     {%{config | commands: [{:script, h} | config.commands]}, t}
   end
 
-  defp parse_iex([h | t] = list, config) 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
 
@@ -419,32 +328,22 @@ 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
@@ -452,7 +351,7 @@ 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
@@ -460,7 +359,7 @@ 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
@@ -470,7 +369,7 @@ 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
@@ -480,12 +379,7 @@ 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
@@ -498,36 +392,12 @@ 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 =
-            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]
-            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,
+            each_file: fn file -> if config.verbose_compile do IO.puts "Compiled #{file}" end end)
+        end
       {:missing, missing} ->
         {:error, "No files matched pattern(s) #{Enum.join(missing, ",")}"}
     end
@@ -535,24 +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
 
@@ -570,7 +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

@@ -3,41 +3,38 @@
 defmodule Kernel.ErrorHandler do
   @moduledoc false
 
-  @spec undefined_function(module, atom, list) :: term
   def undefined_function(module, fun, args) do
-    ensure_loaded(module) or ensure_compiled(module, :module, :raise)
+    ensure_loaded(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)
     :error_handler.undefined_lambda(module, fun, args)
   end
 
-  @spec ensure_loaded(module) :: boolean
-  def ensure_loaded(module) do
-    case :code.ensure_loaded(module) do
-      {:module, _} -> true
-      {:error, _} -> false
-    end
+  def release() do
+    # On release, no longer allow elixir_ensure_compiled
+    # directives and revert to the original error handler.
+    # Note we should not delete the elixir_compiler_pid though,
+    # as we still want to send notifications to the compiler.
+    :erlang.erase(:elixir_ensure_compiled)
+    :erlang.process_flag(:error_handler, :error_handler)
+    :ok
   end
 
-  @spec ensure_compiled(module, atom, atom) :: :found | :not_found | :deadlock
-  # Never wait on nil because it should never be defined.
-  def ensure_compiled(nil, _kind, _deadlock) do
-    :not_found
-  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})
-    :erlang.garbage_collect(self())
-
-    receive do
-      {^ref, value} -> value
+  defp ensure_loaded(module) do
+    case Code.ensure_loaded(module) do
+      {:module, _} -> :ok
+      {:error, _} ->
+        parent = :erlang.get(:elixir_compiler_pid)
+        ref    = :erlang.make_ref
+        send parent, {:waiting, :module, self(), ref, module}
+        :erlang.garbage_collect(self)
+        receive do
+          {^ref, :ready}   -> :ok
+          {^ref, :release} -> release()
+        end
     end
   end
 end

lib/elixir/lib/kernel/lexical_tracker.ex

@@ -1,91 +1,85 @@
-# This is an Elixir module responsible for tracking references
-# to modules, remote dispatches, and the usage of
-# aliases/imports/requires in the Elixir scope.
+# This is an Elixir module responsible for tracking
+# the usage of aliases, imports and requires in the Elixir scope.
+#
+# The implementation simply stores dispatch information in an
+# ETS table and then consults this table once compilation is done.
 #
 # Note that since this is required for bootstrap, we can't use
 # any of the `GenServer.Behaviour` conveniences.
 defmodule Kernel.LexicalTracker do
   @moduledoc false
-  @timeout :infinity
+  @timeout 30_000
   @behaviour :gen_server
 
   @doc """
-  Returns all references in this lexical scope.
+  Returns all remotes linked to in this lexical scope.
   """
-  def references(pid) do
-    :gen_server.call(pid, :references, @timeout)
+  def remotes(arg) do
+    :gen_server.call(to_pid(arg), :ets, @timeout)
+    |> :ets.match({{:mode, :'$1'}, :'$2'})
+    |> partition([], [])
+  end
+
+  defp partition([[remote, :compile]|t], compile, runtime),
+    do: partition(t, [remote|compile], runtime)
+  defp partition([[remote, :runtime]|t], compile, runtime),
+    do: partition(t, compile, [remote|runtime])
+  defp partition([], compile, runtime),
+    do: {compile, runtime}
+
+  @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.
+  # 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)
+    :gen_server.cast(pid, :stop)
   end
 
   @doc false
-  def add_require(pid, module) when is_atom(module) do
-    :gen_server.cast(pid, {:add_require, module})
+  def add_import(pid, module, line, warn) do
+    :gen_server.cast(pid, {:add_import, module, line, warn})
   end
 
   @doc false
-  def add_import(pid, module, fas, line, warn) when is_atom(module) do
-    :gen_server.cast(pid, {:add_import, module, fas, line, warn})
-  end
-
-  @doc false
-  def add_alias(pid, module, line, warn) when is_atom(module) do
+  def add_alias(pid, module, line, warn) do
     :gen_server.cast(pid, {:add_alias, module, line, warn})
   end
 
   @doc false
-  def remote_dispatch(pid, module, mode) when is_atom(module) do
+  def remote_dispatch(pid, module, mode) do
     :gen_server.cast(pid, {:remote_dispatch, 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 import_dispatch(pid, module) do
+    :gen_server.cast(pid, {:import_dispatch, module})
   end
 
   @doc false
-  def alias_dispatch(pid, module) when is_atom(module) do
+  def alias_dispatch(pid, module) 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)
@@ -97,104 +91,61 @@ defmodule Kernel.LexicalTracker do
   end
 
   defp unused(pid, tag) do
-    :gen_server.call(pid, {:unused, tag}, @timeout)
+    :gen_server.call(pid, :ets, @timeout)
+    |> :ets.select([{{{tag, :"$1"}, :"$2"}, [is_integer: :"$2"], [{{:"$1", :"$2"}}]}])
+    |> Enum.sort
   end
 
   # Callbacks
 
-  def init(:ok) do
-    state = %{
-      directives: %{},
-      references: %{},
-      exports: %{},
-      cache: %{},
-      compile_env: :ordsets.new(),
-      file: nil
-    }
-
-    {:ok, state}
+  def init(dest) do
+    {:ok, {:ets.new(__MODULE__, [:protected]), 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
-
-    {:reply, Enum.sort(directives), state}
+  def handle_call(:ets, _from, {d, dest}) do
+    {:reply, d, {d, dest}}
   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(:dest, _from, {d, dest}) do
+    {:reply, dest, {d, dest}}
   end
 
-  def handle_call({:read_cache, key}, _from, %{cache: cache} = state) do
-    {:reply, Map.get(cache, key), state}
+  def handle_cast({:remote_dispatch, module, mode}, {d, dest}) do
+    add_compile(d, module, mode)
+    {:noreply, {d, dest}}
   end
 
-  def handle_call(:stop, _from, state) do
-    {:stop, :normal, :ok, state}
+  def handle_cast({:import_dispatch, module}, {d, dest}) do
+    add_dispatch(d, module, :import)
+    # Always compile time because we depend
+    # on the module at compile time
+    add_compile(d, module, :compile)
+    {:noreply, {d, dest}}
   end
 
-  def handle_cast({:write_cache, key, value}, %{cache: cache} = state) do
-    {:noreply, %{state | cache: Map.put(cache, key, value)}}
+  def handle_cast({:alias_dispatch, module}, {d, dest}) do
+    add_dispatch(d, module, :alias)
+    {:noreply, {d, dest}}
   end
 
-  def handle_cast({:remote_dispatch, module, mode}, state) do
-    references = add_reference(state.references, module, mode)
-    {:noreply, %{state | references: references}}
+  def handle_cast({:add_import, module, line, warn}, {d, dest}) do
+    add_directive(d, module, line, warn, :import)
+    {:noreply, {d, dest}}
   end
 
-  def handle_cast({:import_dispatch, module, {function, arity}, mode}, state) do
-    state = add_import_dispatch(state, module, function, arity, mode)
-    {:noreply, state}
+  def handle_cast({:add_alias, module, line, warn}, {d, dest}) do
+    add_directive(d, module, line, warn, :alias)
+    {:noreply, {d, dest}}
   end
 
-  def handle_cast({:alias_dispatch, module}, state) 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)
-      |> add_directive(module, line, warn, :import)
-
-    directives =
-      Enum.reduce(fas, directives, fn {function, arity}, directives ->
-        add_directive(directives, {module, function, arity}, line, warn, :import)
-      end)
-
-    {:noreply, %{state | directives: directives}}
-  end
-
-  def handle_cast({:add_alias, module, line, warn}, state) do
-    {:noreply, %{state | directives: add_directive(state.directives, module, line, warn, :alias)}}
+  def handle_cast(:stop, {d, dest}) do
+    {:stop, :normal, {d, dest}}
   end
 
   @doc false
-  def handle_info(_msg, state) do
-    {:noreply, state}
+  def handle_info(_msg, {d, dest}) do
+    {:noreply, {d, dest}}
   end
 
   @doc false
@@ -207,45 +158,21 @@ defmodule Kernel.LexicalTracker do
     {:ok, state}
   end
 
-  defp partition([{remote, :compile} | t], compile, runtime),
-    do: partition(t, [remote | compile], runtime)
-
-  defp partition([{remote, :runtime} | t], compile, runtime),
-    do: partition(t, compile, [remote | runtime])
-
-  defp partition([], compile, runtime), do: {compile, runtime}
-
   # Callbacks helpers
 
-  defp add_reference(references, module, :compile) when is_atom(module),
-    do: Map.put(references, module, :compile)
-
-  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)
-    end
-  end
-
-  defp add_import_dispatch(state, module, function, arity, mode) do
-    directives =
-      state.directives
-      |> add_dispatch(module, :import)
-      |> add_dispatch({module, function, arity}, :import)
-
-    references = add_reference(state.references, module, mode)
-    %{state | directives: directives, references: references}
-  end
-
-  # In the map we keep imports and aliases.
+  # In the table we keep imports and aliases.
+  # If the value is false, it was not imported/aliased
   # If the value is a line, it was imported/aliased and has a pending warning
   # If the value is true, it was imported/aliased and used
-  defp add_directive(directives, module_or_mfa, line, warn, tag) do
-    marker = if warn, do: line, else: true
-    Map.put(directives, {tag, module_or_mfa}, marker)
+  defp add_dispatch(d, module, tag) do
+    :ets.insert(d, {{tag, module}, true})
   end
 
-  defp add_dispatch(directives, module_or_mfa, tag) do
-    Map.put(directives, {tag, module_or_mfa}, true)
+  defp add_compile(d, module, :runtime), do: :ets.insert_new(d, {{:mode, module}, :runtime})
+  defp add_compile(d, module, :compile), do: :ets.insert(d, {{:mode, module}, :compile})
+
+  defp add_directive(d, module, line, warn, tag) do
+    marker = if warn, do: line, else: true
+    :ets.insert(d, {{tag, module}, marker})
   end
 end

lib/elixir/lib/kernel/parallel_compiler.ex

@@ -1,52 +1,8 @@
 defmodule Kernel.ParallelCompiler do
   @moduledoc """
-  A module responsible for compiling and requiring files in parallel.
+  A module responsible for compiling files in parallel.
   """
 
-  @typedoc "The line. 0 indicates no line."
-  @type line() :: non_neg_integer()
-  @type location() :: line() | {line(), column :: non_neg_integer}
-  @type warning() :: {file :: Path.t(), location(), message :: String.t()}
-  @type error() :: {file :: Path.t(), line(), message :: String.t()}
-
-  @doc """
-  Starts a task for parallel compilation.
-
-  If you have a file that needs to compile other modules in parallel,
-  the spawned processes need to be aware of the compiler environment.
-  This function allows a developer to create a task that is aware of
-  those environments.
-
-  See `Task.async/1` for more information. The task spawned must be
-  always awaited on by calling `Task.await/1`
-  """
-  @doc since: "1.6.0"
-  def async(fun) when is_function(fun, 0) do
-    case :erlang.get(:elixir_compiler_info) do
-      {compiler, _} ->
-        file = :erlang.get(:elixir_compiler_file)
-        dest = :erlang.get(:elixir_compiler_dest)
-
-        {:error_handler, error_handler} = :erlang.process_info(self(), :error_handler)
-        checker = Module.ParallelChecker.get()
-
-        Task.async(fn ->
-          send(compiler, {:async, self()})
-          Module.ParallelChecker.put(compiler, checker)
-          :erlang.put(:elixir_compiler_info, {compiler, self()})
-          :erlang.put(:elixir_compiler_file, file)
-          dest != :undefined and :erlang.put(:elixir_compiler_dest, dest)
-          :erlang.process_flag(:error_handler, error_handler)
-          fun.()
-        end)
-
-      :undefined ->
-        raise ArgumentError,
-              "cannot spawn parallel compiler task because " <>
-                "the current file is not being compiled/required"
-    end
-  end
-
   @doc """
   Compiles the given files.
 
@@ -55,726 +11,254 @@ defmodule Kernel.ParallelCompiler do
   the current file stops being compiled until the dependency is
   resolved.
 
-  It returns `{:ok, modules, warnings}` or `{:error, errors, warnings}`.
+  If there is an error during compilation or if `warnings_as_errors`
+  is set to `true` and there is a warning, this function will fail
+  with an exception.
 
-  Both errors and warnings are a list of three-element tuples containing
-  the file, line and the formatted error/warning.
-
-  ## Options
+  This function accepts the following options:
 
     * `:each_file` - for each file compiled, invokes the callback passing the
       file
 
-    * `:each_long_compilation` - for each file that takes more than a given
-      timeout (see the `:long_compilation_threshold` option) to compile, invoke
-      this callback passing the file as its argument
-
     * `:each_module` - for each module compiled, invokes the callback passing
       the file, module and the module bytecode
 
-    * `:each_cycle` - after the given files are compiled, invokes this function
-      that should return the following values:
-      * `{:compile, modules, warnings}` - to continue compilation with a list of
-        further modules to compile
-      * `{:runtime, modules, warnings}` - to stop compilation and verify the list
-        of modules because dependent modules have changed
-
-    * `:long_compilation_threshold` - the timeout (in seconds) to check for modules
-      taking too long to compile. For each file that exceeds the threshold, the
-      `:each_long_compilation` callback is invoked. From Elixir v1.11, only the time
-      spent compiling the actual module is taken into account by the threshold, the
-      time spent waiting is not considered. Defaults to `10` seconds.
-
-    * `:profile` - if set to `:time` measure the compilation time of each compilation cycle
-       and group pass checker
-
-    * `:dest` - the destination directory for the BEAM files. When using `compile/2`,
-      this information is only used to properly annotate the BEAM files before
+    * `:dest` - the destination directory for the beam files. When using `files/2`,
+      this information is only used to properly annotate the beam files before
       they are loaded into memory. If you want a file to actually be written to
-      `dest`, use `compile_to_path/3` instead.
-
-    * `:beam_timestamp` - the modification timestamp to give all BEAM files
+      `dest`, use `files_to_path/3` instead.
 
+  Returns the modules generated by each compiled file.
   """
-  @doc since: "1.6.0"
-  @spec compile([Path.t()], keyword()) :: {:ok, [atom], [warning]} | {:error, [error], [warning]}
-  def compile(files, options \\ []) when is_list(options) do
-    spawn_workers(files, :compile, options)
+  def files(files, options \\ [])
+
+  def files(files, options) when is_list(options) do
+    spawn_compilers(files, nil, options)
   end
 
   @doc """
-  Compiles the given files and writes resulting BEAM files into path.
-
-  See `compile/2` for more information.
+  Compiles the given files to the given path.
+  Read `files/2` for more information.
   """
-  @doc since: "1.6.0"
-  @spec compile_to_path([Path.t()], Path.t(), keyword()) ::
-          {:ok, [atom], [warning]} | {:error, [error], [warning]}
-  def compile_to_path(files, path, options \\ []) when is_binary(path) and is_list(options) do
-    spawn_workers(files, {:compile, path}, options)
+  def files_to_path(files, path, options \\ [])
+
+  def files_to_path(files, path, options) when is_binary(path) and is_list(options) do
+    spawn_compilers(files, path, options)
   end
 
-  @doc """
-  Requires the given files in parallel.
-
-  Opposite to compile, dependencies are not attempted to be
-  automatically solved between files.
-
-  It returns `{:ok, modules, warnings}` or `{:error, errors, warnings}`.
-
-  Both errors and warnings are a list of three-element tuples containing
-  the file, line and the formatted error/warning.
-
-  ## Options
-
-    * `:each_file` - for each file compiled, invokes the callback passing the
-      file
-
-    * `:each_module` - for each module compiled, invokes the callback passing
-      the file, module and the module bytecode
-
-  """
-  @doc since: "1.6.0"
-  @spec require([Path.t()], keyword()) ::
-          {:ok, [atom], [warning]} | {:error, [error], [warning]}
-  def require(files, options \\ []) when is_list(options) do
-    spawn_workers(files, :require, options)
-  end
-
-  @doc """
-  Prints a warning returned by the compiler.
-  """
-  @doc since: "1.13.0"
-  @spec print_warning(warning) :: :ok
-  def print_warning({file, location, warning}) do
-    :elixir_errors.print_warning(location, file, warning)
-  end
-
-  @doc false
-  @deprecated "Use Kernel.ParallelCompiler.compile/2 instead"
-  def files(files, options \\ []) when is_list(options) do
-    case spawn_workers(files, :compile, options) do
-      {:ok, modules, _} -> modules
-      {:error, _, _} -> exit({:shutdown, 1})
-    end
-  end
-
-  @doc false
-  @deprecated "Use Kernel.ParallelCompiler.compile_to_path/2 instead"
-  def files_to_path(files, path, options \\ []) when is_binary(path) and is_list(options) do
-    case spawn_workers(files, {:compile, path}, options) do
-      {:ok, modules, _} -> modules
-      {:error, _, _} -> exit({:shutdown, 1})
-    end
-  end
-
-  defp spawn_workers(files, output, options) do
-    {:module, _} = :code.ensure_loaded(Kernel.ErrorHandler)
+  defp spawn_compilers(files, path, options) do
+    true = Code.ensure_loaded?(Kernel.ErrorHandler)
+    compiler_pid = self()
+    :elixir_code_server.cast({:reset_warnings, compiler_pid})
     schedulers = max(:erlang.system_info(:schedulers_online), 2)
-    {:ok, checker} = Module.ParallelChecker.start_link(schedulers)
 
-    try do
-      outcome = spawn_workers(schedulers, checker, files, output, options)
-      {outcome, Code.get_compiler_option(:warnings_as_errors)}
-    else
-      {{:ok, _, [_ | _] = warnings}, true} ->
-        message = "Compilation failed due to warnings while using the --warnings-as-errors option"
-        IO.puts(:stderr, message)
-        {:error, warnings, []}
+    result = spawn_compilers(files, files, path, options, [], [], schedulers, [])
 
-      {{:ok, outcome, warnings}, _} ->
-        beam_timestamp = Keyword.get(options, :beam_timestamp)
-        {:ok, write_module_binaries(outcome, output, beam_timestamp), warnings}
-
-      {{:error, errors, warnings}, true} ->
-        {:error, errors ++ warnings, []}
-
-      {{:error, errors, warnings}, _} ->
-        {:error, errors, warnings}
-    after
-      Module.ParallelChecker.stop(checker)
+    # In case --warning-as-errors is enabled and there was a warning,
+    # compilation status will be set to error.
+    case :elixir_code_server.call({:compilation_status, compiler_pid}) do
+      :ok ->
+        result
+      :error ->
+        IO.puts :stderr, "Compilation failed due to warnings while using the --warnings-as-errors option"
+        exit({:shutdown, 1})
     end
   end
 
-  defp spawn_workers(schedulers, checker, files, output, options) do
-    threshold = Keyword.get(options, :long_compilation_threshold, 10) * 1000
-    timer_ref = Process.send_after(self(), :threshold_check, threshold)
-
-    {outcome, state} =
-      spawn_workers(files, 0, [], [], %{}, [], %{
-        dest: Keyword.get(options, :dest),
-        each_cycle: Keyword.get(options, :each_cycle, fn -> {:runtime, [], []} end),
-        each_file: Keyword.get(options, :each_file, fn _, _ -> :ok end) |> each_file(),
-        each_long_compilation: Keyword.get(options, :each_long_compilation, fn _file -> :ok end),
-        each_module: Keyword.get(options, :each_module, fn _file, _module, _binary -> :ok end),
-        profile: profile_init(Keyword.get(options, :profile)),
-        output: output,
-        timer_ref: timer_ref,
-        long_compilation_threshold: threshold,
-        schedulers: schedulers,
-        checker: checker
-      })
-
-    Process.cancel_timer(state.timer_ref)
-
-    receive do
-      :threshold_check -> :ok
-    after
-      0 -> :ok
-    end
-
-    outcome
-  end
-
-  defp each_file(fun) when is_function(fun, 1), do: fn file, _ -> fun.(file) end
-  defp each_file(fun) when is_function(fun, 2), do: fun
-
-  defp each_file(file, lexical, parent) do
-    ref = Process.monitor(parent)
-    send(parent, {:file_ok, self(), ref, file, lexical})
-
-    receive do
-      ^ref -> :ok
-      {:DOWN, ^ref, _, _, _} -> :ok
-    end
-  end
-
-  defp write_module_binaries(result, {:compile, path}, timestamp) do
-    Enum.flat_map(result, fn
-      {{:module, module}, {binary, _map}} ->
-        full_path = Path.join(path, Atom.to_string(module) <> ".beam")
-        File.write!(full_path, binary)
-        if timestamp, do: File.touch!(full_path, timestamp)
-        [module]
-
-      _ ->
-        []
-    end)
-  end
-
-  defp write_module_binaries(result, _output, _timestamp) do
-    for {{:module, module}, _} <- result, do: module
-  end
-
-  ## Verification
-
-  defp verify_modules(result, warnings, dependent_modules, state) do
-    checker_warnings = maybe_check_modules(result, dependent_modules, state)
-    warnings = Enum.reverse(warnings, checker_warnings)
-    {{:ok, result, warnings}, state}
-  end
-
-  defp maybe_check_modules(result, runtime_modules, state) do
-    %{profile: profile, checker: checker} = state
-
-    compiled_modules =
-      for {{:module, _module}, {_binary, info}} <- result,
-          do: info
-
-    runtime_modules =
-      for module <- runtime_modules,
-          path = :code.which(module),
-          is_list(path) and path != [],
-          do: {module, path}
-
-    profile_checker(profile, compiled_modules, runtime_modules, fn ->
-      Module.ParallelChecker.verify(checker, compiled_modules, runtime_modules)
-    end)
-  end
-
-  defp profile_init(:time), do: {:time, System.monotonic_time(), 0}
-  defp profile_init(nil), do: :none
-
-  defp profile_checker({:time, _, _}, compiled_modules, runtime_modules, fun) do
-    {time, result} = :timer.tc(fun)
-    time = div(time, 1000)
-    num_modules = length(compiled_modules) + length(runtime_modules)
-    IO.puts(:stderr, "[profile] Finished group pass check of #{num_modules} modules in #{time}ms")
-    result
-  end
-
-  defp profile_checker(:none, _compiled_modules, _runtime_modules, fun) do
-    fun.()
-  end
-
-  ## Compiler worker spawning
-
-  # We already have n=schedulers currently running, don't spawn new ones
-  defp spawn_workers(
-         queue,
-         spawned,
-         waiting,
-         files,
-         result,
-         warnings,
-         %{schedulers: schedulers} = state
-       )
-       when spawned - length(waiting) >= schedulers do
-    wait_for_messages(queue, spawned, waiting, files, result, warnings, state)
+  # We already have 4 currently running, don't spawn new ones
+  defp spawn_compilers(entries, original, output, options, waiting, queued, schedulers, result) when
+      length(queued) - length(waiting) >= schedulers do
+    wait_for_messages(entries, original, output, options, waiting, queued, schedulers, result)
   end
 
   # Release waiting processes
-  defp spawn_workers([{ref, found} | t], spawned, waiting, files, result, warnings, state) do
-    {files, waiting} =
-      case List.keytake(waiting, ref, 2) do
-        {{_kind, pid, ^ref, file_pid, _on, _defining, _deadlock}, waiting} ->
-          send(pid, {ref, found})
-          {update_timing(files, file_pid, :waiting), waiting}
-
-        nil ->
-          # In case the waiting process died (for example, it was an async process),
-          # it will no longer be on the list. So we need to take it into account here.
-          {files, waiting}
-      end
-
-    spawn_workers(t, spawned, waiting, files, result, warnings, state)
+  defp spawn_compilers([h|t], original, output, options, waiting, queued, schedulers, result) when is_pid(h) do
+    {_kind, ^h, ref, _module} = List.keyfind(waiting, h, 1)
+    send h, {ref, :ready}
+    waiting = List.keydelete(waiting, h, 1)
+    spawn_compilers(t, original, output, options, waiting, queued, schedulers, result)
   end
 
-  defp spawn_workers([file | queue], spawned, waiting, files, result, warnings, state) do
-    %{output: output, dest: dest, checker: checker} = state
+  # Spawn a compiler for each file in the list until we reach the limit
+  defp spawn_compilers([h|t], original, output, options, waiting, queued, schedulers, result) do
     parent = self()
-    file = Path.expand(file)
 
     {pid, ref} =
-      :erlang.spawn_monitor(fn ->
-        Module.ParallelChecker.put(parent, checker)
-        :erlang.put(:elixir_compiler_info, {parent, self()})
-        :erlang.put(:elixir_compiler_file, file)
+      :erlang.spawn_monitor fn ->
+        # Notify Code.ensure_compiled/2 that we should
+        # attempt to compile the module by doing a dispatch.
+        :erlang.put(:elixir_ensure_compiled, true)
 
-        try do
-          case output do
-            {:compile, path} -> compile_file(file, path, parent)
-            :compile -> compile_file(file, dest, parent)
-            :require -> require_file(file, parent)
+        # Set the elixir_compiler_pid used by our custom Kernel.ErrorHandler.
+        :erlang.put(:elixir_compiler_pid, parent)
+        :erlang.process_flag(:error_handler, Kernel.ErrorHandler)
+
+        exit(try do
+          _ = if output do
+            :elixir_compiler.file_to_path(h, output)
+          else
+            :elixir_compiler.file(h, Keyword.get(options, :dest))
           end
+          {:shutdown, h}
         catch
           kind, reason ->
-            send(parent, {:file_error, self(), file, {kind, reason, __STACKTRACE__}})
-        end
+            {:failure, kind, reason, System.stacktrace}
+        end)
+      end
 
-        exit(:shutdown)
-      end)
-
-    file_data = %{
-      pid: pid,
-      ref: ref,
-      file: file,
-      timestamp: System.monotonic_time(),
-      compiling: 0,
-      waiting: 0,
-      warned: false
-    }
-
-    files = [file_data | files]
-    spawn_workers(queue, spawned + 1, waiting, files, result, warnings, state)
+    spawn_compilers(t, original, output, options, waiting,
+                    [{pid, ref, h}|queued], schedulers, result)
   end
 
-  # No more queue, nothing waiting, this cycle is done
-  defp spawn_workers([], 0, [], [], result, warnings, state) do
-    cycle_return = each_cycle_return(state.each_cycle.())
-    state = cycle_timing(result, state)
+  # No more files, nothing waiting, queue is empty, we are done
+  defp spawn_compilers([], _original, _output, _options, [], [], _schedulers, result) do
+    for {:module, mod} <- result, do: mod
+  end
 
-    case cycle_return do
-      {:runtime, dependent_modules, extra_warnings} ->
-        verify_modules(result, extra_warnings ++ warnings, dependent_modules, state)
-
-      {:compile, [], extra_warnings} ->
-        verify_modules(result, extra_warnings ++ warnings, [], state)
-
-      {:compile, more, extra_warnings} ->
-        spawn_workers(more, 0, [], [], result, extra_warnings ++ warnings, state)
+  # Queued x, waiting for x: POSSIBLE ERROR! Release processes so we get the failures
+  defp spawn_compilers([], original, output, options, waiting, queued, schedulers, result) when length(waiting) == length(queued) do
+    Enum.each queued, fn {child, _, _} ->
+      {_kind, ^child, ref, _module} = List.keyfind(waiting, child, 1)
+      send child, {ref, :release}
     end
+    wait_for_messages([], original, output, options, waiting, queued, schedulers, result)
   end
 
-  # files x, waiting for x: POSSIBLE ERROR! Release processes so we get the failures
-
-  # Single entry, just release it.
-  defp spawn_workers(
-         [],
-         1,
-         [{_, pid, ref, _, _, _, _}] = waiting,
-         [%{pid: pid}] = files,
-         result,
-         warnings,
-         state
-       ) do
-    spawn_workers([{ref, :not_found}], 1, waiting, files, result, warnings, state)
+  # No more files, but queue and waiting are not full or do not match
+  defp spawn_compilers([], original, output, options, waiting, queued, schedulers, result) do
+    wait_for_messages([], original, output, options, waiting, queued, schedulers, result)
   end
 
-  # Multiple entries, try to release modules.
-  defp spawn_workers([], spawned, waiting, files, result, warnings, state)
-       when length(waiting) == spawned do
-    # There is potentially a deadlock. We will release modules with
-    # the following order:
-    #
-    #   1. Code.ensure_compiled/1 checks without a known definition (deadlock = soft)
-    #   2. Code.ensure_compiled/1 checks with a known definition (deadlock = soft)
-    #   3. Struct/import/require/ensure_compiled! checks without a known definition (deadlock = hard)
-    #   4. Modules without a known definition
-    #   5. Code invocation (deadlock = raise)
-    #
-    # The reason for step 3 and 4 is to not treat typos as deadlocks and
-    # help developers handle those sooner. However, this can have false
-    # positives in case multiple modules are defined in the same file
-    # and the module we are waiting for is defined later on.
-    #
-    # Finally, note there is no difference between hard and raise, the
-    # difference is where the raise is happening, inside the compiler
-    # or in the caller.
-
-    deadlocked =
-      deadlocked(waiting, :soft, false) ||
-        deadlocked(waiting, :soft, true) || deadlocked(waiting, :hard, false) ||
-        without_definition(waiting, files)
-
-    if deadlocked do
-      spawn_workers(deadlocked, spawned, waiting, files, result, warnings, state)
-    else
-      errors = handle_deadlock(waiting, files)
-      {{:error, errors, warnings}, state}
-    end
-  end
-
-  # No more queue, but spawned and length(waiting) do not match
-  defp spawn_workers([], spawned, waiting, files, result, warnings, state) do
-    wait_for_messages([], spawned, waiting, files, result, warnings, state)
-  end
-
-  defp compile_file(file, path, parent) do
-    :erlang.process_flag(:error_handler, Kernel.ErrorHandler)
-    :erlang.put(:elixir_compiler_dest, path)
-    :elixir_compiler.file(file, &each_file(&1, &2, parent))
-  end
-
-  defp require_file(file, parent) do
-    case :elixir_code_server.call({:acquire, file}) do
-      :required ->
-        send(parent, {:file_cancel, self()})
-
-      :proceed ->
-        :elixir_compiler.file(file, &each_file(&1, &2, parent))
-        :elixir_code_server.cast({:required, file})
-    end
-  end
-
-  defp cycle_timing(_result, %{profile: :none} = state) do
-    state
-  end
-
-  defp cycle_timing(result, %{profile: {:time, cycle_start, module_counter}} = state) do
-    num_modules = count_modules(result)
-    diff_modules = num_modules - module_counter
-    now = System.monotonic_time()
-    time = System.convert_time_unit(now - cycle_start, :native, :millisecond)
-
-    IO.puts(
-      :stderr,
-      "[profile] Finished compilation cycle of #{diff_modules} modules in #{time}ms"
-    )
-
-    %{state | profile: {:time, now, num_modules}}
-  end
-
-  defp count_modules(result) do
-    Enum.count(result, &match?({{:module, _}, _}, &1))
-  end
-
-  # TODO: Deprecate other returns on v1.14
-  defp each_cycle_return({kind, modules, warnings}), do: {kind, modules, warnings}
-  defp each_cycle_return({kind, modules}), do: {kind, modules, []}
-  defp each_cycle_return(modules) when is_list(modules), do: {:compile, modules, []}
-
-  # The goal of this function is to find leaves in the dependency graph,
-  # i.e. to find code that depends on code that we know is not being defined.
-  # Note that not all files have been compiled yet, so they may not be in waiting.
-  defp without_definition(waiting, files) do
-    nillify_empty(
-      for %{pid: pid} <- files,
-          {_, _, ref, ^pid, on, _, _} <- waiting,
-          not defining?(on, waiting),
-          do: {ref, :not_found}
-    )
-  end
-
-  defp deadlocked(waiting, type, defining?) do
-    nillify_empty(
-      for {_, _, ref, _, on, _, ^type} <- waiting,
-          defining?(on, waiting) == defining?,
-          do: {ref, :deadlock}
-    )
-  end
-
-  defp defining?(on, waiting) do
-    Enum.any?(waiting, fn {_, _, _, _, _, defining, _} -> on in defining end)
-  end
-
-  defp nillify_empty([]), do: nil
-  defp nillify_empty([_ | _] = list), do: list
-
   # Wait for messages from child processes
-  defp wait_for_messages(queue, spawned, waiting, files, result, warnings, state) do
-    %{output: output} = state
-
+  defp wait_for_messages(entries, original, output, options, waiting, queued, schedulers, result) do
     receive do
-      {:async, process} ->
-        Process.monitor(process)
-        wait_for_messages(queue, spawned + 1, waiting, files, result, warnings, state)
+      {:struct_available, module} ->
+        available = for {:struct, pid, _, waiting_module} <- waiting,
+                        module == waiting_module,
+                        not pid in entries,
+                        do: pid
 
-      {:available, kind, module} ->
-        available =
-          for {^kind, _, ref, _, ^module, _defining, _deadlock} <- waiting,
-              do: {ref, :found}
+        spawn_compilers(available ++ entries, original, output, options,
+                        waiting, queued, schedulers, [{:struct, module}|result])
 
-        result = Map.put(result, {kind, module}, true)
-        spawn_workers(available ++ queue, spawned, waiting, files, result, warnings, state)
-
-      {:module_available, child, ref, file, module, binary, checker_info} ->
-        state.each_module.(file, module, binary)
+      {:module_available, child, ref, file, module, binary} ->
+        if callback = Keyword.get(options, :each_module) do
+          callback.(file, module, binary)
+        end
 
         # Release the module loader which is waiting for an ack
-        send(child, {ref, :ack})
+        send child, {ref, :ack}
 
-        available =
-          for {:module, _, ref, _, ^module, _defining, _deadlock} <- waiting,
-              do: {ref, :found}
+        available = for {_kind, pid, _, waiting_module} <- waiting,
+                        module == waiting_module,
+                        not pid in entries,
+                        do: pid
 
-        result = Map.put(result, {:module, module}, {binary, checker_info})
-        spawn_workers(available ++ queue, spawned, waiting, files, result, warnings, state)
+        spawn_compilers(available ++ entries, original, output, options,
+                        waiting, queued, schedulers, [{:module, module}|result])
 
-      # If we are simply requiring files, we do not add to waiting.
-      {:waiting, _kind, child, ref, _file_pid, _on, _defining, _deadlock} when output == :require ->
-        send(child, {ref, :not_found})
-        spawn_workers(queue, spawned, waiting, files, result, warnings, state)
+      {:waiting, kind, child, ref, on} ->
+        defined = fn {k, m} -> on == m and k in [kind, :module] end
 
-      {:waiting, kind, child_pid, ref, file_pid, on, defining, deadlock?} ->
-        # If we already got what we were waiting for, do not put it on waiting.
-        # If we're waiting on ourselves, send :found so that we can crash with
-        # a better error.
-        {files, waiting} =
-          if Map.has_key?(result, {kind, on}) or on in defining do
-            send(child_pid, {ref, :found})
-            {files, waiting}
-          else
-            files = update_timing(files, file_pid, :compiling)
-            {files, [{kind, child_pid, ref, file_pid, on, defining, deadlock?} | waiting]}
-          end
-
-        spawn_workers(queue, spawned, waiting, files, result, warnings, state)
-
-      :threshold_check ->
-        files =
-          for data <- files do
-            if data.warned or List.keymember?(waiting, data.pid, 1) do
-              data
-            else
-              data = update_timing(data, :compiling)
-              data = maybe_warn_long_compilation(data, state)
-              data
-            end
-          end
-
-        timer_ref = Process.send_after(self(), :threshold_check, state.long_compilation_threshold)
-        state = %{state | timer_ref: timer_ref}
-        spawn_workers(queue, spawned, waiting, files, result, warnings, state)
-
-      {:warning, file, location, message} ->
-        file = file && Path.absname(file)
-        message = :unicode.characters_to_binary(message)
-        warning = {file, location, message}
-        wait_for_messages(queue, spawned, waiting, files, result, [warning | warnings], state)
-
-      {:file_ok, child_pid, ref, file, lexical} ->
-        state.each_file.(file, lexical)
-        send(child_pid, ref)
-
-        discard_down(child_pid)
-        new_files = discard_and_maybe_log_file(files, child_pid, state)
-
-        # Sometimes we may have spurious entries in the waiting list
-        # because someone invoked try/rescue UndefinedFunctionError
-        new_waiting = List.keydelete(waiting, child_pid, 1)
-        spawn_workers(queue, spawned - 1, new_waiting, new_files, result, warnings, state)
-
-      {:file_cancel, child_pid} ->
-        discard_down(child_pid)
-        new_files = Enum.reject(files, &(&1.pid == child_pid))
-        spawn_workers(queue, spawned - 1, waiting, new_files, result, warnings, state)
-
-      {:file_error, child_pid, file, {kind, reason, stack}} ->
-        print_error(file, kind, reason, stack)
-        discard_down(child_pid)
-        files |> Enum.reject(&(&1.pid == child_pid)) |> terminate()
-        {{:error, [to_error(file, kind, reason, stack)], warnings}, state}
-
-      {:DOWN, ref, :process, pid, reason} ->
-        waiting = List.keydelete(waiting, pid, 1)
-
-        case handle_down(files, ref, reason) do
-          :ok -> wait_for_messages(queue, spawned - 1, waiting, files, result, warnings, state)
-          {:error, errors} -> {{:error, errors, warnings}, state}
+        # Oops, we already got it, do not put it on waiting.
+        if :lists.any(defined, result) do
+          send child, {ref, :ready}
+        else
+          waiting = [{kind, child, ref, on}|waiting]
         end
+
+        spawn_compilers(entries, original, output, options, waiting, queued, schedulers, result)
+
+      {:DOWN, _down_ref, :process, down_pid, {:shutdown, file}} ->
+        if callback = Keyword.get(options, :each_file) do
+          callback.(file)
+        end
+
+        # Sometimes we may have spurious entries in the waiting
+        # list because someone invoked try/rescue UndefinedFunctionError
+        new_entries = List.delete(entries, down_pid)
+        new_queued  = List.keydelete(queued, down_pid, 0)
+        new_waiting = List.keydelete(waiting, down_pid, 1)
+        spawn_compilers(new_entries, original, output, options, new_waiting, new_queued, schedulers, result)
+
+      {:DOWN, down_ref, :process, _down_pid, reason} ->
+        handle_failure(down_ref, reason, entries, waiting, queued)
+        wait_for_messages(entries, original, output, options, waiting, queued, schedulers, result)
     end
   end
 
-  defp update_timing(files, pid, key) do
-    Enum.map(files, fn data ->
-      if data.pid == pid do
-        time = System.monotonic_time()
-        %{data | key => data[key] + time - data.timestamp, timestamp: time}
-      else
-        data
+  defp handle_failure(ref, reason, entries, waiting, queued) do
+    if file = find_failure(ref, queued) do
+      print_failure(file, reason)
+
+      if all_missing?(entries, waiting, queued) do
+        collect_failures(queued, length(queued) - 1)
       end
-    end)
-  end
 
-  defp update_timing(data, key) do
-    time = System.monotonic_time()
-    %{data | key => data[key] + time - data.timestamp, timestamp: time}
-  end
+      Enum.each queued, fn {child, _, _} ->
+        Process.exit(child, :kill)
+      end
 
-  defp maybe_warn_long_compilation(data, state) do
-    compiling = System.convert_time_unit(data.compiling, :native, :millisecond)
-
-    if not data.warned and compiling >= state.long_compilation_threshold do
-      state.each_long_compilation.(data.file)
-      %{data | warned: true}
-    else
-      data
+      exit({:shutdown, 1})
     end
   end
 
-  defp discard_and_maybe_log_file(files, pid, state) do
-    Enum.reject(files, fn data ->
-      if data.pid == pid do
-        data = update_timing(data, :compiling)
-        data = maybe_warn_long_compilation(data, state)
-
-        if state.profile != :none do
-          compiling = to_padded_ms(data.compiling)
-          waiting = to_padded_ms(data.waiting)
-          relative = Path.relative_to_cwd(data.file)
-
-          IO.puts(
-            :stderr,
-            "[profile] #{compiling}ms compiling + #{waiting}ms waiting for #{relative}"
-          )
-        end
-
-        true
-      else
-        false
-      end
-    end)
+  defp find_failure(ref, queued) do
+    case List.keyfind(queued, ref, 1) do
+      {_child, ^ref, file} -> file
+      _ -> nil
+    end
   end
 
-  defp to_padded_ms(time) do
-    time
-    |> System.convert_time_unit(:native, :millisecond)
-    |> Integer.to_string()
-    |> String.pad_leading(6, " ")
+  defp print_failure(_file, {:shutdown, _}) do
+    :ok
   end
 
-  defp discard_down(pid) do
+  defp print_failure(file, {:failure, kind, reason, stacktrace}) do
+    IO.puts "\n== Compilation error on file #{Path.relative_to_cwd(file)} =="
+    IO.puts Exception.format(kind, reason, prune_stacktrace(stacktrace))
+  end
+
+  defp print_failure(file, reason) do
+    IO.puts "\n== Compilation error on file #{Path.relative_to_cwd(file)} =="
+    IO.puts Exception.format(:exit, reason, [])
+  end
+
+  @elixir_internals [:elixir, :elixir_exp, :elixir_compiler, :elixir_module, :elixir_clauses,
+                     :elixir_translator, :elixir_expand, :elixir_lexical, :elixir_exp_clauses,
+                     :elixir_def]
+
+  defp prune_stacktrace([{mod, _, _, _}|t]) when mod in @elixir_internals do
+    prune_stacktrace(t)
+  end
+
+  defp prune_stacktrace([h|t]) do
+    [h|prune_stacktrace(t)]
+  end
+
+  defp prune_stacktrace([]) do
+    []
+  end
+
+  defp all_missing?(entries, waiting, queued) do
+    entries == [] and waiting != [] and
+      length(waiting) == length(queued)
+  end
+
+  defp collect_failures(_queued, 0), do: :ok
+
+  defp collect_failures(queued, remaining) do
     receive do
-      {:DOWN, _, :process, ^pid, _} -> :ok
+      {:DOWN, down_ref, :process, _down_pid, reason} ->
+        if file = find_failure(down_ref, queued) do
+          print_failure(file, reason)
+          collect_failures(queued, remaining - 1)
+        else
+          collect_failures(queued, remaining)
+        end
+    after
+      # Give up if no failure appears in 5 seconds
+      5000 -> :ok
     end
   end
-
-  defp handle_down(_files, _ref, :normal) do
-    :ok
-  end
-
-  defp handle_down(files, ref, reason) do
-    case Enum.find(files, &(&1.ref == ref)) do
-      %{pid: pid, file: file} ->
-        print_error(file, :exit, reason, [])
-        files |> Enum.reject(&(&1.pid == pid)) |> terminate()
-        {:error, [to_error(file, :exit, reason, [])]}
-
-      nil ->
-        :ok
-    end
-  end
-
-  defp handle_deadlock(waiting, files) do
-    deadlock =
-      for %{pid: pid, file: file} <- files do
-        {:current_stacktrace, stacktrace} = Process.info(pid, :current_stacktrace)
-        Process.exit(pid, :kill)
-
-        {kind, ^pid, _, _, on, _, _} = List.keyfind(waiting, pid, 1)
-        description = "deadlocked waiting on #{kind} #{inspect(on)}"
-        error = CompileError.exception(description: description, file: nil, line: nil)
-        print_error(file, :error, error, stacktrace)
-        {Path.relative_to_cwd(file), on, description}
-      end
-
-    IO.puts("""
-
-    Compilation failed because of a deadlock between files.
-    The following files depended on the following modules:
-    """)
-
-    max =
-      deadlock
-      |> Enum.map(&(&1 |> elem(0) |> String.length()))
-      |> Enum.max()
-
-    for {file, mod, _} <- deadlock do
-      IO.puts(["  ", String.pad_leading(file, max), " => " | inspect(mod)])
-    end
-
-    IO.puts(
-      "\nEnsure there are no compile-time dependencies between those files " <>
-        "and that the modules they reference exist and are correctly named\n"
-    )
-
-    for {file, _, description} <- deadlock, do: {Path.absname(file), nil, description}
-  end
-
-  defp terminate(files) do
-    for %{pid: pid} <- files, do: Process.exit(pid, :kill)
-    for %{pid: pid} <- files, do: discard_down(pid)
-    :ok
-  end
-
-  defp print_error(file, kind, reason, stack) do
-    IO.write([
-      "\n== Compilation error in file #{Path.relative_to_cwd(file)} ==\n",
-      Kernel.CLI.format_error(kind, reason, stack)
-    ])
-  end
-
-  defp to_error(file, kind, reason, stack) do
-    line = get_line(file, reason, stack)
-    file = Path.absname(file)
-    message = :unicode.characters_to_binary(Kernel.CLI.format_error(kind, reason, stack))
-    {file, line || 0, message}
-  end
-
-  defp get_line(_file, %{line: line}, _stack) when is_integer(line) and line > 0 do
-    line
-  end
-
-  defp get_line(file, :undef, [{_, _, _, []}, {_, _, _, info} | _]) do
-    if Keyword.get(info, :file) == to_charlist(Path.relative_to_cwd(file)) do
-      Keyword.get(info, :line)
-    end
-  end
-
-  defp get_line(file, _reason, [{_, _, _, [file: 'expanding macro']}, {_, _, _, info} | _]) do
-    if Keyword.get(info, :file) == to_charlist(Path.relative_to_cwd(file)) do
-      Keyword.get(info, :line)
-    end
-  end
-
-  defp get_line(file, _reason, [{_, _, _, info} | _]) do
-    if Keyword.get(info, :file) == to_charlist(Path.relative_to_cwd(file)) do
-      Keyword.get(info, :line)
-    end
-  end
-
-  defp get_line(_, _, _) do
-    nil
-  end
 end

lib/elixir/lib/kernel/parallel_require.ex

@@ -1,17 +1,85 @@
 defmodule Kernel.ParallelRequire do
-  @moduledoc false
+  @moduledoc """
+  A module responsible for requiring files in parallel.
+  """
 
-  @deprecated "Use Kernel.ParallelCompiler.require/2 instead"
-  def files(files, callbacks \\ [])
+  @doc """
+  Requires the given files.
 
-  def files(files, callback) when is_function(callback, 1) do
-    files(files, each_file: callback)
+  A callback that is invoked every time a file is required
+  can be optionally given as argument.
+
+  Returns the modules generated by each required file.
+  """
+  def files(files, callback \\ fn x -> x end) do
+    compiler_pid = self()
+    :elixir_code_server.cast({:reset_warnings, compiler_pid})
+    schedulers = max(:erlang.system_info(:schedulers_online), 2)
+    result = spawn_requires(files, [], callback, 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, "Compilation failed due to warnings while using the --warnings-as-errors option"
+        exit({:shutdown, 1})
+    end
   end
 
-  def files(files, options) when is_list(options) do
-    case Kernel.ParallelCompiler.require(files, options) do
-      {:ok, modules, _} -> modules
-      {:error, _, _} -> exit({:shutdown, 1})
+  defp spawn_requires([], [], _callback, _schedulers, result), do: result
+
+  defp spawn_requires([], waiting, callback, schedulers, result) do
+    wait_for_messages([], waiting, callback, schedulers, result)
+  end
+
+  defp spawn_requires(files, waiting, callback, schedulers, result) when length(waiting) >= schedulers do
+    wait_for_messages(files, waiting, callback, schedulers, result)
+  end
+
+  defp spawn_requires([h|t], waiting, callback, schedulers, result) do
+    parent = self()
+    {pid, ref} = :erlang.spawn_monitor fn ->
+      :erlang.put(:elixir_compiler_pid, parent)
+
+      exit(try do
+        new = Code.require_file(h) || []
+        {:required, Enum.map(new, &elem(&1, 0)), h}
+      catch
+        kind, reason ->
+          {:failure, kind, reason, System.stacktrace}
+      end)
+    end
+
+    spawn_requires(t, [{pid, ref}|waiting], callback, schedulers, result)
+  end
+
+  defp wait_for_messages(files, waiting, callback, schedulers, result) do
+    receive do
+      {:DOWN, ref, :process, pid, status} ->
+        tuple = {pid, ref}
+        if tuple in waiting do
+          case status do
+            {:required, mods, file} ->
+              callback.(file)
+              result  = mods ++ result
+              waiting = List.delete(waiting, tuple)
+            {:failure, kind, reason, stacktrace} ->
+              :erlang.raise(kind, reason, stacktrace)
+            other ->
+              :erlang.raise(:exit, other, [])
+          end
+        end
+        spawn_requires(files, waiting, callback, schedulers, result)
+      {:module_available, child, ref, _, _, _} ->
+        send(child, {ref, :ack})
+        spawn_requires(files, waiting, callback, schedulers, result)
+      {:struct_available, _} ->
+        spawn_requires(files, waiting, callback, schedulers, result)
+      {:waiting, :struct, child, ref, _} ->
+        send(child, {ref, :release})
+        spawn_requires(files, waiting, callback, schedulers, result)
     end
   end
 end

lib/elixir/lib/kernel/utils.ex

@@ -3,84 +3,56 @@ import Kernel, except: [destructure: 2, defdelegate: 2, defstruct: 2]
 defmodule Kernel.Utils do
   @moduledoc false
 
-  @doc """
-  Callback for destructure.
-  """
-  def destructure(list, count)
-      when is_list(list) and is_integer(count) and count >= 0,
-      do: destructure_list(list, count)
-
-  def destructure(nil, count)
-      when is_integer(count) and count >= 0,
-      do: destructure_nil(count)
+  def destructure(list, count) when is_list(list), do: destructure_list(list, count)
+  def destructure(nil, count), do: destructure_nil(count)
 
   defp destructure_list(_, 0), do: []
   defp destructure_list([], count), do: destructure_nil(count)
-  defp destructure_list([h | t], count), do: [h | destructure_list(t, count - 1)]
+  defp destructure_list([h|t], count), do: [h|destructure_list(t, count - 1)]
 
   defp destructure_nil(0), do: []
-  defp destructure_nil(count), do: [nil | destructure_nil(count - 1)]
+  defp destructure_nil(count), do: [nil|destructure_nil(count - 1)]
 
-  @doc """
-  Callback for defdelegate.
-  """
-  def defdelegate(fun, opts) when is_list(opts) do
-    # TODO: Remove on v2.0
-    append_first? = Keyword.get(opts, :append_first, false)
+  def defdelegate(fun, opts, env) do
+    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
+    :ok = check_defdelegate_args(args, env)
+
+    as_args =
+      case append_first and args != [] do
+        true  -> tl(args) ++ [hd(args)]
+        false -> args
       end
 
     as = Keyword.get(opts, :as, name)
-    as_args = build_as_args(args, append_first?)
-
     {name, args, as, as_args}
   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
+  # TODO: Convert this to an error on 1.3
+  defp check_defdelegate_args([], _env),
+    do: :ok
+  defp check_defdelegate_args([{var, _, mod}|rest], env) when is_atom(var) and is_atom(mod),
+    do: check_defdelegate_args(rest, env)
+  defp check_defdelegate_args([code|_], env) do
+    :elixir_errors.warn(env.line, env.file,
+      "defdelegate/2 will only accept variable names in upcoming versions, " <>
+      "got: #{Macro.to_string(code)}")
   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
-  end
-
-  defp validate_arg(ast) do
-    raise ArgumentError,
-          "defdelegate/2 only accepts function parameters, got: #{Macro.to_string(ast)}"
-  end
-
-  @doc """
-  Callback for defstruct.
-  """
   def defstruct(module, fields) do
     case fields do
-      fs when is_list(fs) ->
-        :ok
-
+      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)
@@ -90,224 +62,12 @@ 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)
-  end
-
-  @doc """
-  Announcing callback for defstruct.
-  """
-  def announce_struct(module) do
-    case :erlang.get(:elixir_compiler_info) do
-      :undefined -> :ok
-      {pid, _} -> send(pid, {:available, :struct, module})
-    end
-  end
-
-  @doc """
-  Callback for raise.
-  """
-  def raise(msg) when is_binary(msg) do
-    RuntimeError.exception(msg)
-  end
-
-  def raise(module) when is_atom(module) do
-    module.exception([])
-  end
-
-  def raise(%_{__exception__: true} = exception) 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
+    :maps.put(:__struct__, module, :maps.from_list(fields))
   end
 end

lib/elixir/lib/list/chars.ex

@@ -1,63 +1,56 @@
 defprotocol List.Chars do
   @moduledoc ~S"""
-  The `List.Chars` protocol is responsible for
-  converting a structure to a charlist (only if applicable).
+  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_char_list` which does the conversion.
 
-  The only function that must be implemented is
-  `to_charlist/1` which does the conversion.
-
-  The `to_charlist/1` function automatically imported
-  by `Kernel` invokes this protocol.
+  The `to_char_list` function automatically imported
+  by Kernel invokes this protocol.
   """
 
-  @doc """
-  Converts `term` to a charlist.
-  """
-  @spec to_charlist(t) :: charlist
-  def to_charlist(term)
-
-  @doc false
-  @deprecated "Use List.Chars.to_charlist/1 instead"
-  Kernel.def to_char_list(term) do
-    __MODULE__.to_charlist(term)
-  end
+  def to_char_list(thing)
 end
 
 defimpl List.Chars, for: Atom do
-  def to_charlist(nil), do: ''
-
-  def to_charlist(atom), do: Atom.to_charlist(atom)
+  def to_char_list(atom), do: Atom.to_char_list(atom)
 end
 
 defimpl List.Chars, for: BitString do
   @doc """
-  Returns the given binary `term` converted to a charlist.
+  Returns the given binary converted to a char list.
   """
-  def to_charlist(term) when is_binary(term) do
-    String.to_charlist(term)
+  def to_char_list(thing) when is_binary(thing) do
+    String.to_char_list(thing)
   end
 
-  def to_charlist(term) do
+  def to_char_list(thing) do
     raise Protocol.UndefinedError,
-      protocol: @protocol,
-      value: term,
-      description: "cannot convert a bitstring to a charlist"
+             protocol: @protocol,
+                value: thing,
+          description: "cannot convert a bitstring to a char list"
   end
 end
 
 defimpl List.Chars, for: List do
-  # Note that same inlining is used for the rewrite rule.
-  def to_charlist(list), do: list
+  def to_char_list(list), do: list
 end
 
 defimpl List.Chars, for: Integer do
-  def to_charlist(term) do
-    Integer.to_charlist(term)
+  def to_char_list(thing) do
+    Integer.to_char_list(thing)
   end
 end
 
 defimpl List.Chars, for: Float do
-  def to_charlist(term) do
-    :io_lib_format.fwrite_g(term)
+  @digits 20
+  @limit  :math.pow(10, @digits)
+
+  def to_char_list(thing) when thing > @limit do
+    Float.to_char_list(thing, scientific: @digits)
+  end
+
+  def to_char_list(thing) do
+    Float.to_char_list(thing, compact: true, decimals: @digits)
   end
 end