NEWS for Ruby 3.4.0

This document is a list of user-visible feature changes since the 3.3.0 release, except for bug fixes.

Note that each entry is kept to a minimum, see links for details.

Language changes

it is added to reference a block parameter. [Feature #18980]
Keyword splatting nil when calling methods is now supported. **nil is treated similar to **{}, passing no keywords, and not calling any conversion methods. [Bug #20064]

Core classes updates

Note: We're only listing outstanding class updates.

Stdlib updates

The following default gems are updated.

RubyGems 3.6.0.dev
bundler 2.6.0.dev
erb 4.0.4
fiddle 1.1.3
io-console 0.7.2
irb 1.12.0
net-http 0.4.1
prism 0.24.0
reline 0.4.3
stringio 3.1.1
strscan 3.1.1

The following bundled gems are updated.

minitest 5.22.2
test-unit 3.6.2
net-ftp 0.3.4
net-imap 0.4.10
net-smtp 0.4.0.1
rbs 3.4.4
typeprof 0.21.11
debug 1.9.1

The following bundled gems are promoted from default gems.

mutex_m 0.2.0
getoptlong 0.2.1
base64 0.2.0
bigdecimal 3.1.6
observer 0.1.2
abbrev 0.1.2
resolv-replace 0.1.1
rinda 0.2.0
drb 2.2.1
nkf 0.2.0
syslog 0.1.2
csv 3.2.8

See GitHub releases like GitHub Releases of Logger or changelog for details of the default gems or bundled gems.

Supported platforms

Compatibility issues

Error messages and backtrace displays have been changed.
- Use a single quote instead of a backtick as a opening quote. Feature #16495
- Display a class name before a method name (only when the class has a permanent name). Feature #19117
- Kernel#caller, Thread::Backtrace::Location's methods, etc. are also changed accordingly.
```
Old:
test.rb:1:in `foo': undefined method `time' for an instance of Integer
        from test.rb:2:in `<main>'

New:
test.rb:1:in 'Object#foo': undefined method 'time' for an instance of Integer
        from test.rb:2:in `<main>'
```

Stdlib compatibility issues

C API updates

Implementation improvements

Array#each is rewritten in Ruby for better performance [Feature #20182].

JIT