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kotlinlang

Hey,
which option do you think is better, or maybe you have another idea?

a) Option A
```class DoSomethingUseCase {

    fun handle(command: DoSomethingCommand) {
        TODO("not yet implemented")
    }
}

data class DoSomethingCommand(
    val someValue: String
) ```
b) Option B
```class DoSomethingUseCase {

    fun handle(command: Command) {
        TODO("not yet implemented")
    }

    data class Command(
        val someValue: String
    )
}```

Where the ’Command` types are used primarily by the use case have generally nested them (your Option B) to reflect that coupling.  There are times where some of those nested types evolved have a slightly wider audience, at which point will move them out as a top level class to stand on their own.

I don't like to nest unless the inner class needs access to the outer object's state (very rare)