We are pleased to announce the release of Ruby 3.1.0. Ruby 3.1 keeps
compatibility with Ruby 3.0 and also adds many features.
## YJIT: New experimental in-process JIT compiler
Ruby 3.1 merges YJIT, a new in-process JIT compiler developed by Shopify.
Since [Ruby 2.6 introduced MJIT in
2018](Ruby 2.6.0 Released),
its performance greatly improved, and finally [we achieved Ruby3x3
last year](Ruby 3.0.0 Released).
But even though Optcarrot has shown impressive speedups, the JIT
hasn't benefited real world business applications.
Recently Shopify contributed many Ruby improvements to speed up their
Rails application. YJIT is an important contribution, and aims to
improve the performance of Rails applications.
Though MJIT is a method-based JIT compiler and uses an external C
compiler, YJIT uses Basic Block Versioning and includes JIT compiler
inside it. With Lazy Basic Block Versioning (LBBV) it first compiles
the beginning of a method, and incrementally compiles the rest when
the type of arguments and variables are dynamically determined. See
[YJIT: a basic block versioning JIT compiler for
CRuby](https://dl.acm.org/doi/10.1145/3486606.3486781) for a detailed
introduction.
With this technology, YJIT achieves both fast warmup time and
performance improvements on most real-world software, up to 22% on
railsbench, 39% on liquid-render.
YJIT is still an experimental feature, and as such, it is disabled by
default. If you want to use this, specify the `--yjit` command-line
option to enable YJIT. It is also limited to Unix-like x86-64
platforms for now.
* Feature #18229: Proposal to merge YJIT - Ruby master - Ruby Issue Tracking System
* YJIT: Building a New JIT Compiler for CRuby — Development (2021)
* [EN] YJIT - Building a new JIT Compiler inside CRuby / Maxime Chevalier-Boisvert @maximecb - YouTube
## debug gem: A new debugger
A completely rewritten debugger
[debug.gem](GitHub - ruby/debug: Debugging functionality for Ruby) is bundled. debug.gem has
the following features:
* Improve the debugging performance (it does not slow down the
application even with the debugger)
* Support remote debugging
* Support rich debugging frontend (VSCode and Chrome browser are supported now)
* Support multi-process/multi-thread debugging
* Colorful REPL
* And other useful features like recod & replay feature, tracing
feature and so on.
<video autoplay="autoplay" controls="controls" muted="muted"
width="764" height="510"
poster="https://cache.ruby-lang.org/pub/media/ruby310_debug_demo.jpg">
<source src="https://cache.ruby-lang.org/pub/media/ruby310_debug_demo.mp4"
type="video/mp4">
</video>
Ruby had bundled lib/debug.rb, but it was not well maintained and it
had issues about performance and features. debug.gem replaced
lib/debug.rb completely.
## error_highlight: Fine-grained error location in backtrace
A built-in gem, error_highlight, has been introduced. It includes
fine-grained error location in backtrace:
$ ruby test.rb
test.rb:1:in `<main>': undefined method `time' for 1:Integer (NoMethodError)
1.time {}
^^^^^
Did you mean? times
Currently, only `NameError` is supported.
This gem is enabled by default. You can disable it by using a
command-line option `--disable-error_highlight`. See [the
repository](GitHub - ruby/error_highlight) in detail.
## IRB Autocomplete and Document Display
The IRB now has an autocomplete feature, where you can just type in
the code, and the completion candidates dialog will appear. You can
use Tab and Shift+Tab to move up and down.
If documents are installed when you select a completion candidate, the
documentation dialog will appear next to the completion candidates
dialog, showing part of the content. You can read the full document by
pressing Alt+d.
<video autoplay="autoplay" controls="controls" muted="muted"
width="764" height="510"
poster="https://cache.ruby-lang.org/pub/media/ruby310_irb_dialog.png">
<source src="https://cache.ruby-lang.org/pub/media/ruby310_irb_dialog.mp4"
type="video/mp4">
</video>
## Other Notable New Features
### Language
* Values in Hash literals and keyword arguments can be omitted. [Feature #14579]
* `{x:, y:}` is a syntax sugar of `{x: x, y: y}`.
* `foo(x:, y:)` is a syntax sugar of `foo(x: x, y: y)`.
* Pin operator in pattern matching now takes an expression. [Feature #17411]
Prime.each_cons(2).lazy.find_all{_1 in [n, ^(n + 2)]}.take(3).to_a
#=> [[3, 5], [5, 7], [11, 13]]
* Parentheses can be omitted in one-line pattern matching. [Feature #16182]
[0, 1] => _, x
{y: 2} => y:
x #=> 1
y #=> 2
### RBS
RBS is a language to describe the structure of Ruby programs. See [the
repository](GitHub - ruby/rbs: Type Signature for Ruby) for details.
Updates since Ruby 3.0.0:
* Generic type parameters can be bounded.
([PR](Bounded generics by soutaro · Pull Request #844 · ruby/rbs · GitHub))
* Generic type aliases are supported.
([PR](Generic type alias by soutaro · Pull Request #823 · ruby/rbs · GitHub))
* `rbs collection` has been introduced to manage gems' RBSs.
([doc](rbs/collection.md at master · ruby/rbs · GitHub))
* Many signatures for built-in and standard libraries have been added/updated.
* It includes many bug fixes and performance improvements too.
See [the CHANGELOG.md](rbs/CHANGELOG.md at master · ruby/rbs · GitHub)
for more information.
### TypeProf
TypeProf is a static type analyzer for Ruby. It generates a prototype
of RBS from non-type-annotated Ruby code. See [the
document](typeprof/doc.md at master · ruby/typeprof · GitHub) for
detail.
The main updates since Ruby 3.0.0 is an experimental IDE support
called "TypeProf for IDE".
The vscode extension shows a guessed (or explicitly written in a RBS
file) method signature above each method definition, draws a red
underline under the code that may cause a name error or type error,
and completes method names (i.e., shows method candidates). See [the
document](typeprof/ide.md at master · ruby/typeprof · GitHub) in
detail.
Also, the release includes many bug fixes and performance improvements.
## Performance improvements
* MJIT
* For workloads like Rails, the default `--jit-max-cache` is changed
from 100 to 10000.
The JIT compiler no longer skips compilation of methods longer
than 1000 instructions.
* To support Zeitwerk of Rails, JIT-ed code is no longer cancelled
when a TracePoint for class events is enabled.
## Other notable changes since 3.0
* One-line pattern matching, e.g., `ary => [x, y, z]`, is no longer
experimental.
* Multiple assignment evaluation order has been changed slightly.
[[Bug #4443]](Bug #4443: odd evaluation order in a multiple assignment - Ruby master - Ruby Issue Tracking System)
* `foo[0], bar[0] = baz, qux` was evaluated in order `baz`, `qux`,
`foo`, and then `bar` in Ruby 3.0. In Ruby 3.1, it is evaluated in
order `foo`, `bar`, `baz`, and then `qux`.
* Variable Width Allocation: Strings (experimental) [[Bug
#18239]](https://bugs.ruby-lang.org/issues/18239)
* Psych 4.0 changes `Psych.load` as `safe_load` by the default.
You may need to use Psych 3.3.2 for migrating to this behavior.
[[Bug #17866]](Bug #17866: Incompatible changes with Psych 4.0.0 - Ruby master - Ruby Issue Tracking System)
### Standard libraries updates
* The following default gem are updated.
* RubyGems 3.3.3
* base64 0.1.1
* benchmark 0.2.0
* bigdecimal 3.1.1
* bundler 2.3.3
* cgi 0.3.1
* csv 3.2.2
* date 3.2.2
* did_you_mean 1.6.1
* digest 3.1.0
* drb 2.1.0
* erb 2.2.3
* error_highlight 0.3.0
* etc 1.3.0
* fcntl 1.0.1
* fiddle 1.1.0
* fileutils 1.6.0
* find 0.1.1
* io-console 0.5.9
* io-wait 0.2.1
* ipaddr 1.2.3
* irb 1.4.1
* json 2.6.1
* logger 1.5.0
* net-http 0.2.0
* net-protocol 0.1.2
* nkf 0.1.1
* open-uri 0.2.0
* openssl 3.0.0
* optparse 0.2.0
* ostruct 0.5.2
* pathname 0.2.0
* pp 0.3.0
* prettyprint 0.1.1
* psych 4.0.3
* racc 1.6.0
* rdoc 6.4.0
* readline 0.0.3
* readline-ext 0.1.4
* reline 0.3.0
* resolv 0.2.1
* rinda 0.1.1
* ruby2_keywords 0.0.5
* securerandom 0.1.1
* set 1.0.2
* stringio 3.0.1
* strscan 3.0.1
* tempfile 0.1.2
* time 0.2.0
* timeout 0.2.0
* tmpdir 0.1.2
* un 0.2.0
* uri 0.11.0
* yaml 0.2.0
* zlib 2.1.1
* The following bundled gems are updated.
* minitest 5.15.0
* power_assert 2.0.1
* rake 13.0.6
* test-unit 3.5.3
* rexml 3.2.5
* rbs 2.0.0
* typeprof 0.21.1
* The following default gems are now bundled gems. You need to add
the following libraries to `Gemfile` under the bundler environment.
* net-ftp 0.1.3
* net-imap 0.2.2
* net-pop 0.1.1
* net-smtp 0.3.1
* matrix 0.4.2
* prime 0.1.2
* debug 1.4.0
See [NEWS](https://github.com/ruby/ruby/blob/ruby_3_1_0/NEWS.md)
or [commit logs](https://github.com/ruby/ruby/compare/v3_0_0...ruby_3_1_0)
for more details.
With those changes, [3124 files changed, 551760 insertions(+), 99167
deletions(-)](https://github.com/ruby/ruby/compare/v3_0_0...ruby_3_1_0#file_bucket)
since Ruby 3.0.0!
Merry Christmas, Happy Holidays, and enjoy programming with Ruby 3.1!
## Download
* <https://cache.ruby-lang.org/pub/ruby/3.1/ruby-3.1.0.tar.gz>
SIZE: 20103517
SHA1: e4e8c20dd2a1fdef4d3e5bd5a3461000dd17f226
SHA256: 50a0504c6edcb4d61ce6b8cfdbddaa95707195fab0ecd7b5e92654b2a9412854
SHA512: 76009d325e961e601d9a287e36490cbc1f3b5dbf4878fa6eab2c4daa5ff2fed78cbc7525cd87b09828f97cbe2beb30f528928bcc5647af745d03dffe7c5baaa9
* <https://cache.ruby-lang.org/pub/ruby/3.1/ruby-3.1.0.tar.xz>
SIZE: 14709096
SHA1: 92b603c2a69fb25d66c337a63e94280984edea11
SHA256: 1a0e0b69b9b062b6299ff1f6c6d77b66aff3995f63d1d8b8771e7a113ec472e2
SHA512: a2bb6b5e62d5fa06dd9c30cf84ddcb2c27cb87fbaaffd2309a44391a6b110e1dde6b7b0d8c659b56387ee3c9b4264003f3532d5a374123a7c187ebba9293f320
* <https://cache.ruby-lang.org/pub/ruby/3.1/ruby-3.1.0.zip>
SIZE: 24388179
SHA1: e37435956d6f840a0e8758d7374bc7e0e346105f
SHA256: a3bfcd486d09c065d46421da0ff3d430ce4423fefd80cea63c6595d83ae4af0e
SHA512: 67db71144e06da2c1c25eaf413d1417c99a4b18738a573f9e3371c11ea242eee9dcbdc3de17336f25ab5060039fe034e57298943d344be9cd9eb33bb56e2e1c6
## What is Ruby
Ruby was first developed by Matz (Yukihiro Matsumoto) in 1993,
and is now developed as Open Source. It runs on multiple platforms
and is used all over the world especially for web development.
![https://cache.ruby-lang.org/pub/media/ruby310_debug_demo.jpg">](https://cache.ruby-lang.org/pub/media/ruby310_debug_demo.jpg">){kind=link}
![https://cache.ruby-lang.org/pub/media/ruby310_irb_dialog.png">](https://cache.ruby-lang.org/pub/media/ruby310_irb_dialog.png">){kind=link}