module FizzBuzz
  refine Fixnum do
    def fizzbuzz()
      fz = ''
      if (self % 3 == 0) then fz += 'Fizz' end
      if (self % 5 == 0) then fz += 'Buzz' end
      if (fz == '') then self.to_s else fz end
    end
  end
end

eval <<EOB
(1..30).each do |n|
  using FizzBuzz
  puts n.fizzbuzz
end
EOB

puts 42.fizzbuzz