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Hello guys, on a shared library i have a function that returns a kotlin `Result&lt;String&gt;`  how can i parse it in Swift IOS ? I it is giving me `Any?`  value

There are <https://kotlinlang.org/docs/native-objc-interop.html#generics|limitations to Objective-C generics>, which affects interop from Kotlin. You should be able to cast the `Any?` value to `String`. You could create a Swift extension that does this cast to make the API nicer within Swift.

here is my function in kotlin
`suspend fun process() : Result&lt;MyCustom&gt;{}`   what will be the best way to parse it in Swift

I’m not sure this has to do with generics. Value classes can’t be sent over the objc-interop bridge and get cast to whatever their parent type is. Result is a value class so it might have something to do with that.

I’ve seen this behavior of upcasting to `Any?` when using value classes in swift.

Ah, that's true. If it weren't a value class, it would just be one level of generics. It's usually the generic generic types that lose the nested type.

Yup. To be honest I’ve _never_ seen a value class cast to its contained type. Eg.

```value class Foo(val string: Stirng)```
says it should be exposed as String in Swift, but I’ve never seen that. It _always_ gets case to `Any?` for me.

Here's the <https://youtrack.jetbrains.com/issue/KT-32352/inline-classes-are-exported-as-id-to-objc-swift|YouTrack issue>.

In my opinion I wish they would just box across the objc-bridge :shrug:

I think that makes sense as well. Value classes can already be boxed in certain use cases on the JVM. Boxing them in Kotlin/Native would provide access to the value class's API and type safety, only sacrificing the inline optimization.

<@U7YRX6BA4> you can workaround this by defining your own `Result` type that is a regular class, instead of value class.

<@UFX38V9SB> if you could provide a sample that would be helpful. I mean i want to return `Result`  like type with a `success`  class or `failure`  class depending on the operation

```sealed interface MyResult&lt;out T&gt; {
  class Success(val data: T) : MyResult&lt;T&gt;
  class Failure(val e: Throwable) : MyResult&lt;Nothing&gt;
}```

If you want it to be just like the std lib implementation, you can use <https://github.com/JetBrains/kotlin/blob/f4ba5aaf9a287f162cd4290e992aacd96a830922/libraries/stdlib/src/kotlin/util/Result.kt#L22|the source> as a regular non-value class.

This is what I use:

```/**
 * Adapted from [Result](<https://github.com/google/iosched/blob/main/shared/src/main/java/com/google/samples/apps/iosched/shared/result/Result.kt>)
 * this class is used because [Kotlin.Result] can't be accessed from iOS.
 * This class won't be needed once the [Result.kt issue](<https://youtrack.jetbrains.com/issue/KT-32352/inline-classes-are-exported-as-id-to-objc-swift#focus=Comments-27-6766899.0-0>)  is addressed
 */
sealed class Result<out R> {
    data class Success<T>(val data: T) : Result<T>()
    data class Failure(val exception: Exception) : Result<Nothing>()

}

/**
 * `true` if [Result] is of type [Success] & holds non-null [Success.data].
 */
val Result<*>.isSuccess
    get() = this is Result.Success && data != null

val <T> Result<T>.data: T? get() = (this as? Result.Success)?.data

val <T> Result<T>.failureData: Exception? get() = (this as? Result.Failure)?.exception```