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kotlinlang

I have a `sealed interface MyInterface` where every implementor is `MySealedClass()` (why? because `MySealedClass` is a huge class and I need a subset of the subclasses). is there any way to make Kotlin understand this property?
the best I can think of is to give the interface an infallible `fun toMySealedClass(): MySealedClass = when (this) { is MySealedClass -> this }` function which statically validates this property, but ideally I'd like not having to keep using it every time I have something that is `MyInterface` and instead have Kotlin understand that it's a `MySealedClass`.

Does MySealedClass need to be a class? Maybe you can extract an interface out of it, and then have MyInterface implement that

yes, `MySealedClass` is a major, already-existing class. it is unlikely that I'll be allowed to significantly change it.

Maybe some time later the compiler can infer that there's only one subtype for `MyInterface` and automatically cast that into `MySealedClass`, but it may also break the code too bad if even later another subtype for `MyInterface` is needed, as known as "extensibility hurts".