Category: ruby-2.4.0

• String supports Unicode case mappings

  String/Symbol#upcase/downcase/swapcase/capitalize(!) now handle Unicode case mappings instead of only ASCII case mappings

• String#concat, Array#concat and String#prepend Now takes multiple arguments.

  Now String#concat, Array#concat and String#prepend

  • String#concat

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          # Before 2.4.0
    
    

• Binding#irb Start a REPL session similar to binding.pry

  Ruby 2.4.0 introduced new feature for debugging