Sebastian Berg <sebast...@sipsolutions.net> added the comment:
Fully, agree! In the end, `PyType_FromSpec` replaces `type.__new__()` (and init I guess) when working in C. In Python, we would call `type.__new__` (maybe via super) from the `metatype.__new__`, but right now, in C, the metatype cannot reliably use `PyType_FromSpec` in its own `metatype.__new__` to do the same. I agree with the scenarios: * If we do not have a custom `metatype.__new__` (init?) then `PyType_FromSpec` should have no reason to refuse doing the work, because nothing can go wrong. * If we do have a custom `tp_new` the user has to provide C API to create the metaclass instance. But they still need a way to call `type.__new__` in C (i.e. get what `PyType_FromSpec` does, and promising to do the rest). `PyType_ApplySpec` would provide that way to create a custom `metatype.__new__` in C when `PyType_FromSpec()` would otherwise reject it to make the first scenario safe. A flag probably can do the same. I have no preference, `ApplySpec` seems great to me. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue45383> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
