On Sun, Nov 28, 2021 at 09:33:17PM -0800, Paul Bryan wrote: > 1. Noted: Python's for statement will happily iterate over an object > that only implements __next__.
That is not correct. >>> class C(object): ... def __next__(self): ... return 1 ... >>> for i in C(): ... print(i) ... Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'C' object is not iterable > 2. The documentation is pretty clear on what is expected of an > iterator: implement __next__ and __iter__. That goes back to the PEP introducing the iterator protocol in version 2.1. This is not something new. > 3. It is perfectly reasonable for __iter__ to return something other > than self; the documentation already reflects this. Right. Your object can return anything it likes from `__iter__`. But then the object isn't an iterator itself, it is an iterable. That is perfectly fine, many wonderful objects that are iterable aren't iterators (e.g. lists, strings, dicts, sets, etc). -- Steve _______________________________________________ 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/F36FF6LBAZ4L2BV7WGPWFSIHGHGHBA33/ Code of Conduct: http://python.org/psf/codeofconduct/
