On 15 September 2016 at 21:11, אלעזר <elaz...@gmail.com> wrote: > Yes the "class A[T]:" syntax requires on the ability to express variance as > an operator, but not the other way around. > > It might be an argument in favor of switching to the + syntax: to make > possible future syntax change in class definition somewhat easier to > swallow.
A future syntax change is very unlikely, as people encountering "class SomeName(Generic[+T]):" for the first time can easily google "python generic class" and hopefully find useful answers in the documentation for typing.Generic. By contrast, "class SomeName[+T]:" would have to be covered directly in the class statement documentation, which runs completely counter to the notion of type hints as executable code annotations (rather than being an unavoidable core part of the language the way they are in statically typed languages). 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/
