Marco Sulla <launchpad....@marco.sulla.e4ward.com> added the comment:
I asked why on StackOverflow, and an user seemed to find the reason. The problem for him/her is in `update_one_slot()`. `dict` implements directly `__contains__()` and `__getitem__()`. Usually, `sq_contains` and `mp_subscript` are wrapped to implement `__contains__()` and `__getitem__()`, but this way `dict` is a little faster. The problem is that `update_one_slot()` searches for the wrappers. If it does not find them, it does not inherit the `__contains__()` and `__getitem__()` of the class, but create a `__contains__()` and `__getitem__()` functions that do an MRO search and call the superclass method. This is why `__contains__()` and `__getitem__()` of `dict` subclasses are slower. Is it possible to modify `update_one_slot()` so that, if no wrapper is found, the explicit implementation is inherited? SO answer: https://stackoverflow.com/a/59914459/1763602 ---------- components: +C API -Interpreter Core nosy: +Marco Sulla versions: +Python 3.9 -Python 3.8 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue34396> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
