The `completionHandler` for `suspend` functions only excepts an `Error`, but on the Kotlin side I wa...

# compose

[Brian Guertin]

The completionHandler for suspend functions only excepts an Error, but on the Kotlin side I want to catch a specific exception type e.g. MyException. How do I pass MyException to the completionHandler?

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

Did you mean to post this in #coroutines ?

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

Which completion handler are you talking about?

[Brian Guertin]

I'm using coroutines but this issue is not specific to coroutines in any way.

When you write this in Kotlin:

@Throws(MyException::class)
suspend fun myFunction(): Boolean

[Brian Guertin]

Then on the Swift/ObjC side, the function gets defined as completionHandler(KotlinBoolean?, NSError?), so I'm not sure how to pass MyException over.

[Brian Guertin]

I ended up just changing my return type instead of dealing with it (so my return type now includes the error cases as well). I think what I'm asking for is just not supported by ObjC interop 🤷

[Brian Guertin]

Oh, but I did mean to post this in #ios, whoops

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

ah, yea i know nothing about obj-c integration 😅