On Thu, Jul 9, 2020, at 15:32, Dominik Vilsmeier wrote: > On 09.07.20 21:04, Ethan Furman wrote: > > I'm having a hard time understanding this line: > > > > if lower == upper is not None: > > > > As near as I can tell, `upper is not None` will be either True or > > False, meaning the condition will only ever be True if `lower` is also > > either True or False, and since I would not expect `lower` to ever be > > True or False, I expect this condition to always fail. Am I missing > > something? > > > It's operator chaining and shorthand notation for > (https://docs.python.org/3/reference/expressions.html#comparisons) > > if (lower == upper) and upper is not None:
If PEP-8 does not currently forbid using the shorthand notation in cases other than relational/equality operators in the same general direction [e.g. A > B == C >= D] or like equivalence operators [E is F is G; H == I == J], I think it should. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/JDNR63FOM2O6AKCKEW6SMSDI5VQNHMBX/ Code of Conduct: http://python.org/psf/codeofconduct/
