Dennis Sweeney wrote: -----------------------
It appears that in CPython, self[:] is self is true for base str objects, so I think return self[:] is consistent with (1) the premise that returning self is an implementation detail that is neither mandated nor forbidden, and (2) the premise that the methods should return base str objects even when called on str subclasses.
Ethan Furman wrote: -------------------
The Python interpreter in my head sees self[:] and returns a copy.
Dennis Sweeney wrote: -----------------------
I think I'm still in the camp that ``return self[:]`` more precisely prescribes the desired behavior. It would feel strange to me to write ``return self`` and then say "but you don't actually have to return self, and in fact you shouldn't when working with subclasses".
I don't understand that list bit -- surely, if I'm bothering to implement `removeprefix` and `removesuffix` in my subclass, I would also want to `return self` to keep my subclass? Why would I want to go through the extra overhead of either calling my own `__getitem__` method, or have the `str.__getitem__` method discard my subclass? However, if you are saying that `self[:]` *will* call `self.__class__.__getitem__` so my subclass only has to override `__getitem__` instead of `removeprefix` and `removesuffix`, that I can be happy with. -- ~Ethan~ _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/GTSUGU3CLYGS6R6DPEPNKD4IBN6PESGW/ Code of Conduct: http://python.org/psf/codeofconduct/
