Handle "value classes" interoperability

[ValentinDenis]

Hi everyone,

We would like to expose our use cases made in our KMP library to our swift app.

Right now we have to create special data class return types so swift can handle it.

Here is an example:

class GetCustomAppsUseCase(
    private val customAppRepository: CustomAppRepository,
) {
    suspend operator fun invoke(): CustomAppsResult {
        val customApps: Result<List<VolatileCustomApp>> =
            customAppRepository.getRemoteCustomApps()
        return CustomAppsResult(
            customApps = customApps.getOrNull() ?: emptyList(),
            error = customApps.exceptionOrNull()
        )
    }
}

data class CustomAppsResult(
    val customApps: List<VolatileCustomApp>,
    val error: Throwable?
) : DaxiumResult(error)

It's used in swift with :

func getCustomApps() throws -> [VolatileCustomApp]? {
        let result = LoginFeature.shared.getCustomApps.invoke()
        if let error = result.error?.asError() {
            throw error
        } else {
            return result.customapps
        }
    }

What would be great is if Result type could be interoperable so that we could get rid of our data class and directly use an enum on the Result on the swift side, as it is possible with sealed class with SKIE and the swift Result type.

Do you know if something like this can be done ?
What is your recommendation on handling Result type ?

Thank you !

[FilipDolnik]

Hi! I think that we have inline classes somewhere in our backlog. However, we don't have a clear idea of what that would look like.

As for your use case, I think the easiest solution is to use a different result implementation based on a sealed class instead of a value class.