module Mulaka
  def self.grazuila(a, b, &block)
    p instance_eval &block
  end
end

class Object
  def grazuila(a, b=nil, &block)
    Mulaka.grazuila(a, b, &block)
  end
end

grazuila "foztabul" do
  puts "wouldn't you love to know"

  grazuila "gztorla" do
    puts "why the fuck someone would"
  end
end

68-26-244-235:rubinius brian$ ruby describe.rb
describe.rb:3: warning: parenthesize argument(s) for future version
wouldn't you love to know
describe.rb:16:in `grazuila': wrong number of arguments (1 for 2) (ArgumentError)
        from describe.rb:16
        from describe.rb:3:in `instance_eval'
        from describe.rb:3:in `grazuila'
        from describe.rb:9:in `grazuila'
        from describe.rb:13

68-26-244-235:rubinius brian$ shotgun/rubinius describe.rb
wouldn't you love to know
An exception has occurred:
    wrong number of arguments (got 1, required 2) (ArgumentError)

Backtrace:
                 Mulaka.grazuila at describe.rb:2
            Module#__script__ {} at describe.rb:16
    Kernel(Module)#instance_eval at kernel/core/eval.rb:135
                 Mulaka.grazuila at describe.rb:3
                 Object#grazuila at describe.rb:9
               Object#__script__ at describe.rb:13
        CompiledMethod#as_script at kernel/core/compiled_method.rb:359
             Compile.single_load at kernel/core/compile.rb:252
     Compile.load_from_extension at kernel/core/compile.rb:324
               Object#__script__ at kernel/loader.rb:204