ruby--ruby/NEWS.md

NEWS for Ruby 3.1.0

This document is a list of user visible feature changes since the 3.0.0 release, except for bug fixes.

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

Language changes

Command line options

Core classes updates

Outstanding ones only.

• Enumerable

  • Enumerable#compact is added. [Feature #17312]

• Enumerator::Lazy

  • Enumerator::Lazy#compact is added. [Feature #17312]

• Module

  • Module#prepend now modifies the ancestor chain if the receiver already includes the argument. Module#prepend still does not modify the ancestor chain if the receiver has already prepended the argument. [Bug #17423]

• Struct

  • Passing only keyword arguments to Struct#initialize is warned. You need to use a Hash literal to set a Hash to a first member. [Feature #16806]

Stdlib updates

Outstanding ones only.

Compatibility issues

Excluding feature bug fixes.

Stdlib compatibility issues

• ERB#initialize warns safe_level and later arguments even without -w. [Feature #14256]

C API updates

Implementation improvements

JIT

• RubyVM::MJIT is renamed to RubyVM::JIT.

Static analysis

RBS

TypeProf

Miscellaneous changes