KO>|<A.rb

#!/usr/bin/env ruby
# -*- coding: utf-8 -*-

def f
  s = gets.chomp

  z = Class.new
  z.class_eval do
    define_method :ma do
      s * 2
    end

    define_method :mb do
      s.reverse
    end
  end

  z.new
end

a = f
puts a.ma
puts a.mb