Any advice on how to approach this problem? I want to use `MutableStateFlow.compareAndSet()`, but wi...

# flow

[Chris Fillmore]

Any advice on how to approach this problem? I want to use MutableStateFlow.compareAndSet(), but with a `sealed interface`:

sealed interface State {
  object NotConnected : State
  class Connected(val connection: SomeConnection) : State
}

val stateFlow = MutableStateFlow<State>(State.NotConnected)
...
// Obviously doesn't work, can't use State.Connected in this way
stateFlow.compareAndSet(State.Connected, State.NotConnected)

[Chris Fillmore]

It seems I could solve this naively with something like (** edited to add synchronized)

inline fun <T, reified U: T> MutableStateFlow<T>.compareAndSet(update: T): Boolean = synchronized(this) {
  val value = this.value
  return if (value is U) compareAndSet(value, update) else false
}