Hi everyone, I'm writing 2 classes to represent lo...

# announcements

[iex]

Hi everyone, I'm writing 2 classes to represent long running operation state. This works but I wonder if there's a way to improve it (e.g. by making both share an interface)?

sealed class VoidOperationState {
    object Progress: VoidOperationState()
    object Success: VoidOperationState()
    data class Failure(val t: Throwable): VoidOperationState()
}

sealed class OperationState<out T> {
    object Progress: OperationState<Nothing>()
    data class Success<out T>(val data: T): OperationState<T>()
    data class Failure(val t: Throwable): OperationState<Nothing>()
}

(Of course I could make VoidOperationState just an OperationState<Unit> but that's not nice, since I'd have to be always passing the Unit to Success...

[Zach Klippenstein (he/him) [MOD]]

It’s a tradeoff, but I would probably consider having a single type hierarchy worth the teeny bit of boilerplate of passing in Unit.

[Zach Klippenstein (he/him) [MOD]]

You can also create a factory function named Success that takes no arguments and returns Success(Unit) to get rid of the boilerplate.

[iex]

You're right, using Unit isn't so bad

[iex]

also can create a type alias to alleviate a part of it