The full code is ``` sealed class Async load state lt WaitT ErrorT DoneT gt class Wait lt WaitT ErrorT DoneT gt val wait WaitT Async load state lt WaitT ErrorT DoneT gt class Error lt WaitT ErrorT DoneT gt val error ErrorT Async load state lt WaitT ErrorT DoneT gt class Done lt WaitT ErrorT DoneT gt val done DoneT Async load state lt WaitT ErrorT DoneT gt class Async load lt WaitT ErrorT DoneT gt val w WaitT f Async load lt WaitT ErrorT DoneT gt WaitT gt Unit var state = Async load state Wait lt WaitT ErrorT DoneT gt w init f w fun is done Boolean return when state is Async load state Error lt gt gt true is Async load state Done lt gt gt true else gt false ```

The full code is ``` sealed class Async load state lt WaitT kotlinlang #announcements

06/27/2018, 9:26 AM

The full code is:

sealed class Async_load_state<WaitT, ErrorT, DoneT> () {
    class Wait<WaitT, ErrorT, DoneT>(val wait: WaitT): Async_load_state<WaitT, ErrorT, DoneT>() {}
    class Error<WaitT, ErrorT, DoneT>(val error: ErrorT): Async_load_state<WaitT, ErrorT, DoneT>() {}
    class Done<WaitT, ErrorT, DoneT>(val done: DoneT): Async_load_state<WaitT, ErrorT, DoneT>() {}

}

class Async_load<WaitT, ErrorT, DoneT> (
        val w: WaitT,
        f: Async_load<WaitT, ErrorT, DoneT>.(WaitT) -> Unit) {

    var state = Async_load_state.Wait<WaitT, ErrorT, DoneT>(w)
    init { f(w) }

    fun is_done(): Boolean {
        return when(state) {
            is Async_load_state.Error<*, *, *> -> true
            is Async_load_state.Done<*, *, *> -> true
            else -> false
        }
    }
}

06/27/2018, 3:35 PM

Why wouldn’t you just

sealed class AsyncLoadState() {
  class Wait(val wait: WaitT) : AsyncLoadState()
  class Error(val error: ErrorT) : AsyncLoadState()
  class Done(val done: DoneT) : AsyncLoadState()
}