kotlin-result VS Arrow Meta

Sealed classes in combination with a library like https://github.com/michaelbull/kotlin-result will get you what you need. Essentially at that point you'll be doing error handling the way you would in Rust, where a 1-level deep sealed class containing data classes as children act as the root error type and each of its variants. If you have errors coming from two different domains you just create a wrapper error type for each domain.

This is a great result lib: https://github.com/michaelbull/kotlin-result

Lastly I do not like kotlin's Result and we use the kotlin-result library which is more expressive and not tied to Throwable (similar to Arrow's Either).

In my own code, I started to use explicit error handling. I'm currently experimenting with Result (from https://github.com/michaelbull/kotlin-result) and Raise (from https://arrow-kt.io/).

un-related to multiplatform i've found it extremely helpful to wrap things in a Result type. If something can throw an error, it get's a Result return type. It sounds like that would help your use case too. The built in Result may be useful too

This is a better impl.

Using a result type can help to differentiate quite nicely. https://github.com/michaelbull/kotlin-result

kotlin-result

As of right now, Arrow Meta is the only library I am aware of with which you can productively write compiler plugins.

Thanks for the example, that's interesting.

Note that Kotlin has union types through this compiler plugin: https://github.com/arrow-kt/arrow-meta/issues/570