On Wed, Jan 13, 2021 at 04:47:06AM +1100, Chris Angelico wrote: > That'd leave open > the option for "foo() if x else foo()" to be optimized down to just > "foo()", although I don't think that particular one is needed.
That would be an unsafe optimization. Not all objets are representable as truthy/falsey values, e.g. numpy arrays. >>> bool(a) Traceback (most recent call last): File "<stdin>", line 1, in <module> ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all() Not even all builtin values. This is in Python 3.9: >>> bool(NotImplemented) <stdin>:1: DeprecationWarning: NotImplemented should not be used in a boolean context True I believe that 3.10 makes it an error. If not 3.10, then it will surely happen soon. But even without the change to NotImplemented, it has never been the case that *every* object is guaranteed to be either truthy or falsey. At least not since the Python 1.x `__nonzero__` dunder was put into the language. -- Steve _______________________________________________ Python-Dev mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/[email protected]/message/7Q76EALFDEI2S6L3NFXSJS4TNNEWMO6L/ Code of Conduct: http://python.org/psf/codeofconduct/