Ruby goto (PoC)

goto.rb

module Kernel

  require 'singleton'
  require 'continuation'

  class Env < Hash
    include Singleton

    def initialize
      super
    end
  end

  def label(name)
    callcc { |cc| Env.instance[name] = cc }
  end

  def goto(name)
    raise "Goto couldn't find label: #{name}" unless Env.instance.key?(name)
    Env.instance[name].call
  end

end

poc.rb

require './goto'

def goop(times, &blk)
  label :loop
  blk.call
  goto :loop unless (times-=1).zero?
end

goop(10) {
  puts 'Hi goto!'
}