This document is a list of user-visible feature changes since the 3.2.0 release, except for bug fixes.
Note that each entry is kept to a minimum, see links for details.
- A new
performance
warning category was introduced. They are not displayed by default even in verbose mode. Turn them on with-W:performance
orWarning[:performance] = true
. [Feature #19538] - The
RUBY_GC_HEAP_INIT_SLOTS
environment variable has been deprecated and removed. Environment variablesRUBY_GC_HEAP_%d_INIT_SLOTS
should be used instead. [Feature #19785]
Note: We're only listing outstanding class updates.
-
Array
- Array#pack now raises ArgumentError for unknown directives. [Bug #19150]
-
Dir
- Dir.for_fd added for returning a Dir object for the directory specified by the provided directory file descriptor. [Feature #19347]
- Dir.fchdir added for changing the directory to the directory specified by the provided directory file descriptor. [Feature #19347]
- Dir#chdir added for changing the directory to the directory specified by
the provided
Dir
object. [Feature #19347]
-
MatchData
- MatchData#named_captures now accepts optional
symbolize_names
keyword. [Feature #19591]
- MatchData#named_captures now accepts optional
-
Module
- Module#set_temporary_name added for setting a temporary name for a module. [Feature #19521]
-
ObjectSpace::WeakKeyMap
- New core class to build collections with weak references. The class use equality semantic to lookup keys like a regular hash, but it doesn't hold strong references on the keys. [Feature #18498]
-
Process.warmup
- Notify the Ruby virtual machine that the boot sequence is finished, and that now is a good time to optimize the application. This is useful for long running applications. The actual optimizations performed are entirely implementation specific and may change in the future without notice. [Feature #18885]
-
Process::Status
- Process::Status#& and Process::Status#>> are deprecated. [Bug #19868]
-
Range
- Range#reverse_each can now process beginless ranges with an Integer endpoint. [Feature #18515]
-
Refinement
- Add Refinement#target as an alternative of Refinement#refined_class. Refinement#refined_class is deprecated and will be removed in Ruby 3.4. [Feature #19714]
-
String
- String#unpack now raises ArgumentError for unknown directives. [Bug #19150]
- String#bytesplice now accepts new arguments index/length or range of the source string to be copied. [Feature #19314]
-
RubyGems and Bundler warn if users require gem that is scheduled to become the bundled gems in the future version of Ruby. [Feature #19351] [Feature #19776] [Feature #19843]
Targeted libraries are:
- abbrev
- base64
- bigdecimal
- csv
- drb
- getoptlong
- mutex_m
- nkf
- observer
- resolv-replace
- rinda
- syslog
-
Socket#recv and Socket#recv_nonblock returns
nil
instead of an empty string on closed connections. Socket#recvmsg and Socket#recvmsg_nonblock returnsnil
instead of an empty packet on closed connections. [Bug #19012] -
Random::Formatter#alphanumeric is extended to accept optional
chars
keyword argument. [Feature #18183]
The following default gem is added.
- prism 0.15.1
The following default gems are updated.
- RubyGems 3.5.0.dev
- bigdecimal 3.1.5
- bundler 2.5.0.dev
- csv 3.2.8
- erb 4.0.3
- fiddle 1.1.2
- fileutils 1.7.1
- io-console 0.6.1.dev
- irb 1.8.3
- nkf 0.1.3
- openssl 3.2.0
- optparse 0.4.0.pre.1
- psych 5.1.1.1
- reline 0.3.9
- stringio 3.0.9
- strscan 3.0.7
- syntax_suggest 1.1.0
- time 0.2.2
- timeout 0.4.0
- uri 0.12.2
The following bundled gem is promoted from default gems.
- racc 1.7.1
The following bundled gems are updated.
- minitest 5.20.0
- test-unit 3.6.1
- rexml 3.2.6
- rss 0.3.0
- net-imap 0.4.1
- net-smtp 0.4.0
- rbs 3.2.2
- typeprof 0.21.8
- debug 1.8.0
See GitHub releases like Logger or changelog for details of the default gems or bundled gems.
racc
is promoted to bundled gems.- You need to add
racc
to yourGemfile
if you useracc
under bundler environment.
- You need to add
ext/readline
is retired- We have
reline
that is pure Ruby implementation compatible withext/readline
API. We rely onreline
in the future. If you need to useext/readline
, you can installext/readline
via rubygems.org withgem install readline-ext
. - We no longer need to install libraries like
libreadline
orlibedit
.
- We have
defined?(@ivar)
is optimized with Object Shapes.
- Major performance improvements over 3.2
- Support for splat and rest arguments has been improved.
- Registers are allocated for stack operations of the virtual machine.
- More calls with optional arguments are compiled.
- Exception handlers are also compiled.
- Instance variables no longer exit to the interpreter with megamorphic object shapes.
- Unsupported call types no longer exit to the interpreter.
Integer#!=
,String#!=
,Kernel#block_given?
,Kernel#is_a?
,Kernel#instance_of?
,Module#===
are specially optimized.- Now more than 3x faster than the interpreter on optcarrot!
- Significantly improved memory usage over 3.2
- Metadata for compiled code uses a lot less memory.
- Generate more compact code on ARM64
- Compilation speed is now slightly faster than 3.2.
- Add
RubyVM::YJIT.enable
that can enable YJIT later- You can start YJIT without modifying command-line arguments or environment variables.
- This can also be used to enable YJIT only once your application is
done booting.
--yjit-disable
can be used if you want to use other YJIT options while disabling YJIT at boot.
- Option to disable code GC and treat
--yjit-exec-mem-size
as a hard limit- Can produce better copy-on-write behavior on servers using unicorn and forking
ratio_in_yjit
stat produced by--yjit-stats
is now avaiable in release builds, a special stats or dev build is no longer required to access most stats.- Exit tracing option now supports sampling
--trace-exits-sample-rate=N
- More thorough testing and multiple bug fixes
--yjit-stats=quiet
is added to avoid printing stats on exit.--yjit-perf
is added to facilitate profiling with Linux perf.
- MJIT is removed.
--disable-jit-support
is removed. Consider using--disable-yjit --disable-rjit
instead.
- Introduced a pure-Ruby JIT compiler RJIT.
- RJIT supports only x86_64 architecture on Unix platforms.
- Unlike MJIT, it doesn't require a C compiler at runtime.
- RJIT exists only for experimental purposes.
- You should keep using YJIT in production.