On Thu, Dec 23, 2021 at 3:24 PM Steven D'Aprano <steve@pearwood.info> wrote:
On Thu, Dec 23, 2021 at 02:09:50PM -0800, Guido van Rossum wrote:
Without decorator too (that was Lukasz’ idea). Why bother with the decorator (*if* we were to go there)?
So that
def func(params): pass
creates a function object, and
def func(params)
makes a Callable type object?
No, no, no. That syntax has already been discredited. Mark's proposal was ``` @Callable def func(params): pass ``` My question is, why does it need `@Callable`? Lukasz proposed just using any (undecorated) function, with the convention being that the body is `...` (to which I would add the convention that the function *name* be capitalized, since it is a type). My question (for Mark, or for anyone who supports `@Callable`) is why bother with the decorator. It should be easy to teach a type checker about this: ``` def SomeFn(x: float) -> int: ... def twice(f: SomeFn) -> SomeFn: return lambda x: f(f(x)) ``` -- --Guido van Rossum (python.org/~guido) *Pronouns: he/him **(why is my pronoun here?)* <http://feministing.com/2015/02/03/how-using-they-as-a-singular-pronoun-can-c...>