Supporting Descriptors that override the Implicit Receiver Parameter

Apologies in advance if this sounds more like a bug report than a discussion, however, I was wondering if it would be possible for static type checkers to support descriptors that modify the type passed to the first parameter of a method. For example, in a normal instance method, the type Self@ClassName is passed to the first parameter (which is by convention called self). However, you could decorate that method with a descriptor that changes the type bound to that first parameter. I think it’s...