On Wed, Apr 06, 2016 at 11:30:32AM +0200, Petr Viktorin wrote: > Python was in a similar situation with the .next method on iterators, > which changed to __next__ in Python 3. PEP 3114 (which explains this > change) says: > > > Code that nowhere contains an explicit call to a next method can > > nonetheless be silently affected by the presence of such > > a method. Therefore, this PEP proposes that iterators should have > > a __next__ method instead of a next method (with no change in > > semantics). > > How well does that apply to path/__path__?
I think it's potentially the same. Possibly there are fewer existing uses of "obj.path" out there which conflict with this use, but there's at least one in the std lib: sys.path. > That PEP also introduced the next() builtin. This suggests that a > protocol with __path__/__fspath__ would need a corresponding > path()/fspath() builtin. Not necessarily. Take a look at (say) dir(object()) and you'll see a few dunders that don't correspond to built-ins: __reduce__ and __reduce_ex__ are used by pickle; __sizeof__ is used by sys.getsizeof; __subclasshook__ is used by the ABC system; Another example is __trunc__ used by math.trunc(). So any such fspath function should stand on its own as a useful feature, not just because there's a dunder method __fspath__. -- Steve _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
