require 'rubygems'
require 'eventmachine'
require 'enumerator'

module EventMachine
  # Iteration helpers for asynchronous code
  module Iterator
    def self.mapreduce(enum, map = nil, reduce = nil)
      if enum.any?
        num = enum.size
        results = []

        iterator = nil

        done = proc{ |r|
          results << r
          if (num -= 1) == 0
            reduce.call(results)
          else
            iterator.call
          end
        }

        iterator = proc{
          entry = enum.shift
          map.call(entry, done)
        }
        iterator.call
      end
    end
  end
end

EM.run do
  EM::Iterator.mapreduce([1,2,3], proc{ |n, done|
    EM.add_timer(1){
      done.call([n+1, Time.now])
    }
  }, proc{ |results|
    p results
  })
end