demo monkey patching

monkey.rb

word = 'potato'

puts word.yell # NoMethodError

class ::String
  def yell
    "HEY! #{self.upcase}!"
  end
end

puts word.yell # HEY! POTATO!



module Stupid
  class Server
    def start
      @process = get_new_server_process
      nil
    end

    def stop
      @process.stop
      nil
    end
  end
end

server = Stupid::Server.start
server.stop # too slow... won't stop... can't kill it
server.process # NoMethodError. don't have access to that

module Stupid
  class Server
    def kill
      @process.kill
    end
  end
end

server.kill # there we go