dsl_exp_01.rb

lambda {
  
  hash = {}
  
  Kernel.send :define_method, :say do |sentence, &block|
    hash[sentence] = block
  end
  
  Kernel.send :define_method, :hello do |&block|
    hash.each_pair do |sentence, say|
      block.call sentence, say
    end
  end
  
}.call
 
say "hey dude!" do
  12 > 2
end
 
hello do |sentence, say|
  object = Object.new
  puts "#{sentence}" if object.instance_eval &say # hey dude!
end