On 4/30/07, Bill Janssen <[EMAIL PROTECTED]> wrote: > > [Collin Winter] > > +100 I'm very interested in seeing a lighter weight alternative to abc.py > > that: > > > > 1) is dynamic > > There's no reason ABC's can't be dynamic. > > > 2) doesn't require inheritance to work > > 3) doesn't require mucking with isinstance or other existing mechansims > > Using existing mechanisms that work for the issue is always preferable > to adding new ones that *also* work for the issue.
No existing mechanism would allow PEP 3141 to be distributed as a third-party module and still impact the built-in types; that's what this whole business of __isinstance__ and __issubclass__ is about. In order to achieve dynamic composition, we're having to monkey with fundamental, bedrock properties of inheritance-based object orientation. The definition of "subclass" and "instance" is no longer objective; the answer to "is X an instance of Y?" becomes, "I dunno, ask Y". Collin Winter _______________________________________________ Python-3000 mailing list [email protected] http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
