ruby 2.0.0dev Refinements (Classbox)

refinement.rb

# http://yehudakatz.com/2010/11/30/ruby-2-0-refinements-in-practice/
# http://www.rubyist.net/~matz/20060104.html
# http://www.rubyist.net/~matz/20101113.html

module Foo
  refine String do
    def to_s
      "hello"
    end
  end
end

module Bar
  using Foo
  p "a".to_s
end

p "a".to_s

# => "hello"
# => "a"