For what is worth, that level of differences already exists on pypy and it's really hard to get the *exact* same semantics if things are implemented in python vs C or the other way around.
Example list of differences (which I think OrderedDict already breaks if moved to C): * do methods like items call special methods like __getitem__ (I think it's undecided anyway) * what happens if you take a method and rebind it to another subclass, does it automatically become a method (there are differences between built in and pure python) * atomicity of operations. Some operations used to be non-atomic in Python will be atomic now. I personally think those (and the __class__ issue) are unavoidable On Mon, Oct 19, 2015 at 11:47 PM, Serhiy Storchaka <storch...@gmail.com> wrote: > On 20.10.15 00:00, Guido van Rossum wrote: >> >> Apart from Serhiy's detraction of the 3.5 bug report there wasn't any >> discussion in this thread. I also don't really see any specific >> questions, so maybe you don't have any. Are you just asking whether it's >> okay to merge your code? Or are you asking for more code review? > > > I think Eric ask whether it's okay to have some incompatibility between > Python and C implementations. > > 1. Is it okay to have a difference in effect of __class__ assignment. Pure > Python and extension classes have different restrictions. For example > (tested example this time) following code works with Python implementation > in 3.4, but fails with C implementation in 3.5: > > from collections import OrderedDict > od = OrderedDict() > class D(dict): pass > > od.__class__ = D > > 2. Is it okay to use obj.__class__ in Python implementation and type(obj) in > C implementation for the sake of code simplification? Can we ignore subtle > differences? > > 3. In general, is it okay to have some incompatibility between Python and C > implementations for the sake of code simplification, and where the border > line lies? > > > _______________________________________________ > Python-Dev mailing list > Python-Dev@python.org > https://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: > https://mail.python.org/mailman/options/python-dev/fijall%40gmail.com _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
