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Hey guys, Do you have any good example of <https://medium.com/codex/kotlin-sealed-classes-for-better-handling-of-api-response-6aa1fbd23c76#:~:text=Sealed%20classes%20ensure%20type%20safety,constructors%20are%20private%20by%20default.|Kotlin: Sealed Classes for better handling of API Response> in multiplatform?

```sealed class ApiResult&lt;out R, out E&gt;
data class ApiSuccess&lt;out R&gt;(val value: R) : ApiResult&lt;R, Nothing&gt;()
data class ApiFailure&lt;out E&gt;(
    val status: ApiErrorStatus,
    val details: E?
) : ApiResult&lt;Nothing, E&gt;()```
This is ours. It helps when you have domain specific error response bodies in addition to success bodies.

For example, we have an api that changes an order state. It requires the clients expected state as well as the new state to catch concurrency errors. The details of what the actual state was when it doesn’t match the expected state comes back in a domain specific error body.

Notably we don’t have a loading state, because that’s more of a View/Presenter layer concern, and these objects are just used in the repository/data layer.

Why does the original approach not work for KMP?

The OP was asking for good examples of using sealed classes in multiplatform. The article linked seems like it would work with multiplatform as-is. I was confused about the basis of the question.

Oh for sure, I missed that myself. It seems like it would in fact work

So <@U01G13W294G> why doesn’t it work? Or more precisely, how doesn’t it work?

Hey <@U0232TDAA02> great explanation. As you see in the link, there is function called `fetchResult` inside that code is checking every time `response.code()` and route according to domain specific `Success` or `Error` body. Is there any better way it will automatically route on specific domain rather than checking every time.

Well that’s dependent on what you use to make HTTP calls

The example you linked looks like it uses Retrofit?

<@U0232TDAA02> <@U45FB8RNK> I am using Ktor for api call.

So the implementation will be different then.

I do not have an example using Ktor. For my KMP I use Retrofit on Android and another library for iOS