cancellation

cancellation.scala

  val a1 = for {
    _ <- IO.println("a1")
    _ <- IO.sleep(5.seconds)
  } yield 1

  val a2 = for {
    _ <- IO.println("a2")
    _ <- IO.sleep(5.seconds)
  } yield 2

  val a3 = for {
    _ <- IO.println("a3")
    _ <- IO.sleep(5.seconds)
  } yield 3

  val run = for {
    a <- IO
      .uncancelable(poll =>
        poll(a1).onCancel(IO.println("ca1")) >> poll(a2).onCancel(IO.println("ca2")) >> poll(a3).onCancel(
          IO.println("ca3")))
      .start
    _ <- IO.sleep(8.seconds)
    _ <- a.cancel
  } yield ()

@ run.unsafeRunSync
a1
a2
ca2