def urbanmain() = {

  import M5a._

  import scala.concurrent._
  import scala.concurrent.duration._
  import ExecutionContext.Implicits.global
  import scala.language.postfixOps 

  lazy val f = Future {
    val urban_bench = 
      """>+[<+++++++++++++>-]<[[>+>+<<-]>[<+>-]++++++++
   [>++++++++<-]>.[-]<<>++++++++++[>++++++++++[>++
   ++++++++[>++++++++++[>++++++++++[>++++++++++[>+
   +++++++++[-]<-]<-]<-]<-]<-]<-]<-]++++++++++."""

  assert(run(urban_bench, Map()) == Map(0 -> 10, 5 -> 0, 1 -> 0, 6 -> 0, 2 -> 0, 7 -> 0, 3 -> 0, 4 -> 0))

  }

  Await.result(f, 32 second)
}