On Thu, Aug 27, 2020 at 3:37 PM M.-A. Lemburg <m...@egenix.com> wrote:
> If I'm not mistaken, all those listed cases fall under the second case > I mentioned (branching on length). > > If your API allows for optional list entries, then it's better to > branch on length (e.g. as in the pytest case). If this happens only in > exceptional cases, use try-except (most other cases you listed). > All but the first example, i.e. all the uses of try-except, were found by grepping for `except IndexError`. That was just the easiest method I found to find examples. The fact that try-except was used in those cases does not necessarily mean that the index is missing "only in exceptional cases". Perhaps because you like to emphasise intent when you're coding you assume that "exceptional" is the intent when you see the keyword "except". It's not how I interpret these examples. I think truly exceptional cases would have a change in behaviour like showing a warning. All that's happening here is getting a default value, and using try-except is the easiest available syntax. Often the use case is that the list may be empty or you're at the edge of the list and you need to go one beyond. That's normal and expected, not exceptional. If list.get existed then probably it would have been used in many of these examples. But of course it didn't exist and I don't have a way of searching for custom get functions so nearly all the examples use except which you take to mean exceptional.
_______________________________________________ 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/FPQUJVFKXEEBZBHK5GBCEKPU7IJIZZCS/ Code of Conduct: http://python.org/psf/codeofconduct/
