demonstrates odd Iteratee.foreach behavior

run.scala

object Run extends App {
  import cats._
  import io.iteratee._
  import io.iteratee.internal._

  def e = Enumerator.enumVector[Eval, Int]((0 until 10).toVector)
  def ge = e.grouped(3)

  println("fold ge")
  Iteratee.foreach[Eval,Vector[Int]](println).apply(ge).run.value
  // fold ge
  // Vector(0, 1, 2)
  // Vector(3, 4, 5)
  // Vector(6, 7, 8)
  // Vector(9)

  def e2 = new Enumerator[Eval, Int] {
    val iter = (0 until 10).grouped(3)
    final def apply[A](step: Step[Eval, Int, A]): Eval[Step[Eval, Int, A]] = {
      if (!step.isDone && iter.hasNext) {
        step.feed(iter.next).flatMap(s => apply[A](s))
      } else {
        Now(step)
      }
    }
  }

  def ge2 = e2.grouped(3)

  println("fold ge2")
  Iteratee.foreach[Eval,Vector[Int]](println).apply(ge2).run.value
  // fold ge2
  // Vector(0, 1, 2)
  // Vector(0, 1, 2)
  // Vector(3, 4, 5)
  // Vector(3, 4, 5)
  // Vector(6, 7, 8)
  // Vector(6, 7, 8)
  // Vector(9)
  // ()

}