Why do I need to cast the result of the `map` oper...

# announcements

[tseisel]

Why do I need to cast the result of the map operation in the following sample :

sealed class Request<T> {
    object Pending : Request<Nothing>()
    class Success<T>(val result: T) : Request<T>()
    class Failure(val error: Throwable) : Request<Nothing>()
}

val sourceFlow: Flow<Foo> = getFooFlow()
sourceFlow.map { Request.Success(it) as Request<Foo> }
    .onStart { emit(Request.Pending) }
    .catch { emit(Request.Failure(it) }
    .onEach { ... }
    .launchIn(scope)

Will this kind of issue be fixed by the new Kotlin inference ?
Or is there a workaround (other than creating a typed temporary variable) ?

[Stephan Schroeder]

sourceFlow.map { Request.Success(it) } works fine for me

[tseisel]

@Stephan Schroeder have you tried with onStart, just like in the sample code ? This should trigger a compile error, as Request.Pending is not a Request.Success.

[Stephan Schroeder]

I just checked if IntelliJ flagged an error.

[Stephan Schroeder]

an because I don’t have the Flow dependency, I used a List<Foo> instead