how do I map from a `(Mutable)StateFlow<T>` ...

# coroutines

[andylamax]

how do I map from a (Mutable)StateFlow<T> to another (Mutable)StateFlow<T>? when I call the map method I map the StateFlow<T> to a Flow<T>

[Tim Malseed]

It’s still a MutableStateFlow , you’ve just lost the type inference. You could cast your resulting Flow<T> as a MutableStateFlow<>

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

No, map does not return a StateFlow, it returns a regular Flow. You'd need to use something like stateIn to convert it back.

[Tim Malseed]

Oh, my mistake. I’ll refrain from answering coroutine questions for a few more weeks haha

[Tim Malseed]

I assumed that map just operates on the values after they’re emitting, so the underlying flow could still be a MutableStateFlow. But I guess that doesn’t make sense, since the Flow’s value type has changed (it emits a different type to the one it receives)

[andylamax]

Thank you all for your responses

[andylamax]

very helpful

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

The reason map can't maintain the StateFlow type on its own is explained by Roman in the comments here: https://github.com/Kotlin/kotlinx.coroutines/issues/2081