[Python-Dev] Re: RFC on Callable Syntax PEP

In most of our discussions of this idea, we've assumed that we'd adopt the same semantics that callback protocols use. If we do that, then only `lambda a: 3` will type check. In order to type check both you'd have to make `a` positional-only: ``` def IntToIntFunc(a: int, /) -> int: ... ``` This is one of the reasons I think functions-as-types could be a great idea but not a good substitute for better callable syntax.