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kotlinlang

Is there a way to tell the Kotlin compiler to treat certain Java methods with a `void` return as `Nothing` instead of `Unit`?

That would break the type system.  `void` is isomorphic to `Unit` - they are both sets with exactly one element - whereas `Nothing` is a set with zero elements.  There would be no way for Java to interoperate with Kotlin if `Nothing` was used in place of `void`.

The type checker needs to be able to understand it and they are fundamentally different types

Eh, my guess is writing something to handle that special case of Java not really having an official Nothing type wasn't a high priority for the Kotlin roadmap

Strangely enough it's possible to express what you want in Kotlin with enough function wrapping, although IJ warns that the call is "unreachable code"

That seems like an easier solution than adding exceptions to the type system