On 23 September 2016 at 15:50, Greg Ewing <greg.ew...@canterbury.ac.nz> wrote: > אלעזר wrote: >> >> it feels like a >> placeholder for this meaning would be better. E.g.: >> >> class A: >> def __add__(self, other: CLS) -> CLS: ... > > > That's fine for a class that refers to itself, but > what about classes that refer to each other? This > only addresses a small part of the problem.
Same answer as with any other circular dependency: the code smell is the circular dependency itself, not the awkwardness of the syntax for spelling it. If the string based "circular reference here!" spelling really bothers you, refactor to eliminate the circularity (e.g. by extracting a base class or an implementation independent interface definition), rather than advocating to make the spelling less obnoxious. The difference between that and the "methods referring to the class they're defined in" case is that it's likely to be pretty normal to want to do the latter, so it may prove worthwhile to provide a cleaner standard spelling for it. The counter-argument is the general circularity one above: do you *really* need instances of the particular class being defined? Or is there a more permissive interface based type signature you could specify instead? Or perhaps no type signature at all, and let ducktyping sort it out implicitly at runtime? Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
