On Sun, Aug 21, 2016 at 3:06 PM, Brendan Barnwell <brenb...@brenbarn.net> wrote: > On 2016-08-20 21:10, Chris Angelico wrote: >>> >>> >I think that while the suggestion does bring some benefit, the benefit >>> >isn't enough to make up for the code churn and disruption it would >>> >cause. But I encourage the OP to go through the standard library, pick a >>> >couple of modules, and re-write them to see how they would look using >>> >this proposal. >> >> Python still has a rule that you can iterate over anything that has >> __getitem__, and it'll be called with 0, 1, 2, 3... until it raises >> IndexError. So you have two options: Remove that rule, and require >> that all iterable objects actually define __iter__; or make strings >> non-subscriptable, which means you need to do something like >> "asdf".char_at(0) instead of "asdf"[0]. > > > Isn't the rule that that __getitem__ iteration is available only if > __iter__ is not explicitly defined? So there is a third option: retain > __getitem__ but give this new modified string type an explicit __iter__ that > raises TypeError.
Hmm. It would somehow need to be recognized as "not iterable". I'm not sure how this detection is done; is it based on the presence/absence of __iter__, or is it by calling that method and seeing what comes back? If the latter, then sure, an __iter__ that raises would cover that. ChrisA _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
