On Fri, Sep 27, 2019 at 5:21 PM Guido van Rossum <guido@python.org> wrote:
On Fri, Sep 27, 2019 at 11:18 AM Serhiy Storchaka <storchaka@gmail.com> wrote:
I think it needs an explicit support in the type creation machinery (as __slots__ itself has) to support descriptors and slots with the same name.
That would be tough, since __slots__ is currently implemented by creating a separate descriptor for each slot.
I do think that it would be nice to have a way to automatically create __slots__ from annotations. It would be even nicer if that could be done without copying the class object (as the current state of the art requires: https://github.com/ericvsmith/dataclasses/blob/master/dataclass_tools.py#L23 ).
Thinking aloud, perhaps this could be done by setting __slots__ to a magical value, e.g.
class Point: __slots__ = "__auto__" x: float y: float
This would be independent from the @dataclass decorator (though the decorator may have to be aware of the magic value).
If that's too wacky, we could also use a class keyword argument:
class Point(slots=True): x: float y: float
(Though arguably that's just as wacky. :-)
An argument is less wacky than assigning a magic value to a magic dunder. -gps