Ruby
Ruby 3.1 adds Class#subclasses
Ruby 3.1's new method Class#subclasses returns all classes directly from the receiver without adding singleton classes.Ruby 3.1 adds Class#descendants
With Ruby 3.1, we can use `Class#descendants` to yield the classes that have been directly or indirectly derived from a specific class.
Ruby 3.1 adds MatchData#match and MatchData#match_length
Ruby 3.1 MatchData#match returns the substring corresponding to the argument, while MatchData#match_length returns the length of the captured substring.
Ruby 3.1 allows value omission in hash literals
Ruby 3.1 adds the ability to use hash literals without having a value.
Ruby 3.1 adds try_convert method to Integer class for implicit conversions
try_convert for Integer will convert the object into an instance of the class via the implicit conversion method to_int and returns nil if no implicit conversion method is defined.
Ruby 3.1 introduces pattern matching pin operator against expression
Ruby 3.1 adds support for the expression and range when using the pattern matching pin operator.
Ruby 3.1 adds Enumerable#compact and Enumerator::Lazy#compact
Ruby 3.1 adds Enumerable#compact and Enumerator::Lazy#compact to return a copy of `self` with all `nil` elements removed.
Ruby 3.1 Enumerable#tally now accepts an optional hash to count occurrences
Ruby 3.1 extends the functionality of the Enumerable#tally method introduced in Ruby 2.7. We can now pass another hash whose counts would be added to the resulting tally hash.Ruby 3.1 adds Array#intersect? method
Ruby Array#intersect? method will return true or false based on common elements present in the two arrays.Ruby 3.1 evaluates multiple assignments from left to right
Ruby changes the evaluation order for multiple assignments from left to right making it consistent with single assignment evaluation order.