Starting with Kotlin 2.2.20 you can use the (experimental) Swift export, which provides direct Kotlin - Swift interoperability.

Once Swift export is complete and stable it'll likely completely remove the need for KMP-NativeCoroutines.

So to support you in your journey to Swift export:

• KMP-NativeCoroutines will try to be "compatible" with Swift export as much as possible, allowing you to start testing with Swift export as soon as possible.
• A migration path will be provided once coroutines support in Swift export becomes stable.

Known limitations

These are the known limitations with Swift export and KMP-NativeCoroutines.

🚨 NativeSuspend and NativeFlow are unsupported

At the moment Swift export has some issues with functional return types and generics.

Unfortunately KMP-NativeCoroutines heavily relies on functional return types, making it incompatible with Swift Export. For now the plugin just clones your original functions and properties to prevent your Kotlin builds from failing.

Enabling Swift export

To enable Swift export with KMP-NativeCoroutines you'll need to activate the Swift export compatibility mode:

// build.gradle.kts
nativeCoroutines {
    swiftExport = true
}

Usage

Only some coroutines related code can be used when Swift export is enabled.

Suspend functions

You can use suspend functions as async functions in Swift without any changes:

let letters = try await asyncFunction(for: randomLettersGenerator.getRandomLetters(throwException: throwException))

For Combine and RxSwift there are helper functions available, e.g.:

- let future = createFuture(for: randomLettersGenerator.getRandomLetters(throwException: throwException))
+ let future = createFuture(for: { await self.randomLettersGenerator.getRandomLetters(throwException: throwException) })

Flows

You can use Flows as AsyncSequences without any changes:

let sequence = asyncSequence(for: clock.time)

For Combine and RxSwift there are helper functions available, e.g.:

- let publisher = createPublisher(for: clock.time)
+ let publisher = createPublisher(for: asyncSequence(for: clock.time))