future flatmapping with no stack blowing

gistfile1.scala

scala>   def loop(f: Future[Int]): Future[Int] = {
     |     f.flatMap { i =>
     |       if (i == 1e6) Future.successful(i)
     |       else loop(future(i + 1))
     |     }
     |   }


scala> val f = loop(future(1))

scala> Await.result(f, Duration.Inf)
res1: Int = 1000000

scala>