continueWith

package.scala

    def continueWith[S](cont: Future[T] => S): Future[S] = {
      val p: Promise[S] = Promise()


      f.onComplete {
        case Failure(f) => p.complete(Failure(f))
        case Success(v) => p.completeWith(Future(cont(f)))
      }

      return p.future
    }