On Wed, Apr 3, 2019 at 5:34 AM MRAB <[email protected]> wrote: > > The code above contains a subtle bug. > If suffix == '', then word.endswith(suffix) == True, and > word[:-len(suffix)] == word[:-0] == ''. > > Each time I see someone do that, I see more evidence in support of > adding the method.
Either that, or it's evidence that negative indexing is only part of the story, and we need a real way to express "zero from the end" other than negative zero. For instance, word[:<0] might mean "zero from the end", and word[:<1] would be "one from the end". As a syntactic element rather than an arithmetic one, it would be safe against accidentally slicing from the front instead of the back. But that's an idea for another day. ChrisA _______________________________________________ Python-ideas mailing list [email protected] https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
