Any ideas on a good approach to map C bitfields often used as flags in C functions to a nice typesafe (or at least descriptive/discoverable) Kotlin API ? I'm trying to become an API like

val application = Application("myapp", ApplicationFlags.NONE.or(ApplicationFlags.REPLACE))

where I want the signature to read something like

class Application(val name: String, flags: ApplicationFlags)

So the user does not have to go hunt for random constants.

I talked about this previously herre. https://kotlinlang.slack.com/archives/C0B8Q383C/p1672886309003409

Thanks, that

OptionSet

you proposed in the thread looks interesting.

If you want to do this in an allocation free way I suggest not using the

OptionSet

interface and instead just exposing utility functions atop a

value class

.

I'm still looking into it and experimenting, for the thing I'm working on they are mostly used for infrequent UI-thread method calls, so having the allocation does not hurt performance that much I guess.

The tl;dr on value classes is that if you don’t use them in a way that requires polymorphism (eg referring to it as an interface type), then whatever the value class wraps is what’s passed around in bytecode. There’s no allocations, no pointer chasing, etc.

I've seen it but not used it that much, my general dislike for Compose/SwiftUI/React is the reason I'm looking in KN/GTK...

No problem