1.10.0

Add Application.compile_env/3 and Application.compile_env!/2 for reading values at compilation time and tracking if they accidentally change during runtime

Allow custom calendar representations in calendar sigils

Add c:Calendar.parse_time/1, c:Calendar.parse_date/1, c:Calendar.parse_naive_datetime/1 and c:Calendar.parse_utc_datetime/1 callbacks to calendar behaviour

Add support for NO_COLOR environment variable

Add :token_metadata and :literal_encoder support to Code.string_to_quoted/2

Add compiler tracing to lift events done by the compiler

Return {:error, :unavailable} in Code.ensure_compiled/1 if module is in a deadlock

Add DateTime.now!/2 and DateTime.shift_zone!/3

Speed up getting one random element from enumerables

Add Enum.frequencies/1, Enum.frequencies_by/2, and Enum.map_intersperse/2

Allow a sorting function on Enum.min/max/min_by/max_by

Add asc/desc and compare/1 support to Enum.sort/2

Add version alongside app names in stacktraces

Add Function.identity/1

Add Kernel.is_struct/1 and Kernel.is_map_key/2

Warn when function head comes immediately after the implementation instead of before the implementation

Warn if duplicate key is found in struct declaration

Print all undefined functions as warnings and then raise. This allows users to see all undefined calls at once, when it would otherwise require them to compile the code multiple times

Add Keyword.pop!/2 and Keyword.pop_values/2

Add Map.pop!/2

Optimize multiple operations

Add Module.has_attribute?/2

Add @compile {:no_warn_undefined, mfa_or_module} to turn off undefined function warnings

Add NaiveDateTime.local_now/0

Warn if duplicate key is found in record declaration

Update to Unicode 12.1

Add :encoding option to StringIO and optimize get_chars operation

Support diffs in pattern matching and in assert_receive

Supports capturing named devices in asynchronous tests

Warn on circular file imports when loading default .iex.exs

Allow customization of the continuation prompt on IEx

Allow start_options to be configured on Logger's GenEvent

Integrate Elixir's Logger with Erlang/OTP 21+'s logger. This means setting up the logger level in Elixir will automatically change the logger level for Erlang and vice-versa

Add --profile time flag to profile compilation steps

Add --skip-umbrella-children flag. The new flag does not compile umbrella apps. This is useful for building caches in CD/CI pipelines

Add --check-unused flag. The new flag raises if there are any unused dependencies in the lock file

Allow RELEASE_DISTRIBUTION to be set to none

Support overlays in rel/overlays

Allow configuration reboot to be disabled in releases

Add support for simple round-robin test partitioning across multiple machines

Add MIX_DEPS_PATH environment variable for setting :deps_path

Add Mix.Project.deps_scms/1 that returns deps with their SCMs

Add Mix.Task.Compiler.after_compiler/2 callback, to simplify compilers that may need to run something at multiple steps

compiler_options/0 is deprecated in favor of compiler_option/1

Mix.Config.persist/1 has been deprecated. Instead of Mix.Config.persist(config) use Application.put_all_env(config, persistent: true) (Application.put_all_env/2 was added in v1.9)

calls/0 is deprecated in favor of compiler tracer

The xref.exclude option has been moved to elixirc_options.no_warn_undefined as the xref pass has been moved into the compiler

Code.load_file/2 has been deprecated in favor of Code.require_file/2 or Code.compile_file/2

Code.loaded_files/0 and Code.unload_file/1 have been deprecated in favor of Code.required_files/0 and Code.unrequire_file/1 respectively

Code.ensure_compiled?/1 is deprecated in favor of Code.ensure_compiled/1

String.normalize/2 has been deprecated in favor of :unicode.characters_to_nfc_binary/1 or :unicode.characters_to_nfd_binary/1 which ship as part of Erlang/OTP 20+

Supervisor.Spec.supervise/2 has been deprecated in favor of the new Supervisor child specification

The :simple_one_for_one strategy in Supervisor has been deprecated in favor of DynamicSupervisor

:compile_time_purge_level application environment configuration has been deprecated in favor of the more general :compile_time_purge_matching config

Deprecate logging non-chardata values

This check has been moved into the compiler and has no effect now

This check has been moved into the compiler and has no effect now

This check has been moved into the compiler and has no effect now