Scala Evented Actors

EventActor.scala

import scala.actors.Actor
import Actor._

def buildChain(size: Int, next: Actor): Actor = {
  val a = actor {
    react {
      case 'Die =>
        val from = sender
        if (next != null) {
          next ! 'Die
          react {
            case 'Ack => from ! 'Ack
          }
        } else {
          from ! 'Ack
        }
    }
  }

  if (size > 0) buildChain(size - 1, a)
  else a
}

object EventActor {
  def main(args: Array[String]) {
    val numActors = args(0).toInt
    val start = System.currentTimeMillis
    println("Hello: " + numActors)
    buildChain(numActors, null) ! 'Die

    receive {
      case 'Ack =>
        val end = System.currentTimeMillis
        println("took " + (end - start) + " ms")

      case 'Die =>
        println("End of Actor")
    }
  }
}
EventActor.main(args)