Kotlin coroutines basic example.

Coroutines.kt

// runs the code in the background thread pool
fun asyncOverlay() = async(CommonPool) {
  // start two async operations
  val original = asyncLoadImage("original")
  val overlay = asyncLoadImage("overlay")
  // and then apply overlay to both results
  applyOverlay(original.await(), overlay.await())
}
 
// launches new coroutine in UI context
launch(UI) {
  // wait for async overlay to complete
  val image = asyncOverlay().await()
  // and then show it in UI
  showImage(image)
}