On 5/11/06, Mike Krell <[EMAIL PROTECTED]> wrote: > On 5/11/06, Guido van Rossum <[EMAIL PROTECTED]> wrote: > > I think I'm more comfortable with a maximal taxonomy. In a maximal > > taxonomy, I'd describe a large set of invariants, attributes, > > behavior, etc., and say e.g. "this is how a file behaves". A > > particular class can then claim to be a file by explicitly declaring > > this (how that's spelled is a different issue -- it doesn't need to be > > done by inheritance from an abstract base class or interface, it could > > also be an arbitrary property, agreed upon by convention, or an > > external registry of all file types, for example). > > If the route chosen is "agreed upon by convention" what is the > difference between this and duck typing? Are the "claim" and > "convention" anything more than comments in the code?
The claim should be introspectable. *Conformance* to the claimed API may be hard to introspect but IMO the claims should be introspectable, separate from whatever we (think we) know about hasattr(). -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com