alt Hacker NewsNo you don’t need coercion. You only need polymorphism. The type of `panic!()` could be an arbitrary U, which unifies just fine with the type T here.
Generally languages with such polymorphism have a never type only because they don’t also support impredicative polymorphism.
And then once you have `fn foo<T>() -> T`, what do you write in the body that allows it to typecheck?