sleep-sort.scala

import scala.actors._
import Actor._

def sleepSort(xs : List[Int]) : List[Int] = {
   def sorter(aggregator : Actor, n : Int) = actor {
      reactWithin(n * 1000) {
        case TIMEOUT => {
           aggregator ! n
           exit
        }
      }
   }

   xs map (sorter(self, _)) foreach (_.start)

   val inputLength = xs.length

   def aggregate(result : List[Int], resultLength : Int) : List[Int] = 
     if (resultLength == inputLength) {
        result.reverse 
     } else receive {
        case n : Int => 
          aggregate(n :: result, resultLength + 1)
     }

   aggregate(List[Int](), 0)
}