On Mon, Jul 15, 2013 at 03:34:08PM +1200, Ben Hoyt wrote: > Thanks, Nick -- that's helpful info. Writing such a PEP is a nice idea, but > I think it'd be beyond me (I'm not familiar enough with CPython internals, > protocols, etc). > > Can you explain what you mean by "symmetric protocol rather than the > current only-controlled-by-the-container behaviour"?
Most operators can be controlled by either the left-hand or right-hand operand. For example, x + y can end up calling either x.__add__(y) or y.__radd_(x). The `in` operator is an exception, it only ever calls the container: x in y => y.__contains__(x) but never x.__contained_by__(y) -- Steven _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
