On 26 April 2017 at 02:56, Guido van Rossum <gvanros...@gmail.com> wrote: > In the end I agree with the OP that we should fix this. I don't see a reason > to require a PEP or require updating whatever PEP described this behavior > originally -- PEPs generally describe what should be done to a specific > version of Python, they don't prevent future alterations, and they > essentially represent the historical record, not current documentation. > > I'm a little worried about breaking existing code, but only a little bit, > and this is clearly a gray area, so I think it's okay to change in 3.7 > without deprecations. (But I've been overruled on such matters before, so if > you disagree, speak up now and show us your code!)
This is really obscure behaviour to be relying on, so a porting note + the 3.7 pre-release testing cycles seems like sufficient notice to me. It's potentially also worth checking how PyPy handles these cases - for the only other similar case I'm aware of (the quirks with the relative priority of the nb_* and sq_* slots at the C layer), enough projects relied on the CPython behaviour for them to decide to replicate it, so if they *haven't* replicated the quirk described in the OP, it's a solid data point suggesting there aren't a lot of major projects relying on it. Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
