On Feb 11, 2008 10:40 PM, Neil Toronto <[EMAIL PROTECTED]> wrote: > The problem is that, like all the binary operators, "orderable" is only > defined for pairs of types. A single declaration of orderable-ness > necessarily lacks information needed for type safety.
Actually, lots of languages have ways to express that the values of a given type are orderable. E.g. in C++ you can create a template that takes a single type argument which must define a total ordering using '<'. > Besides probably not being "worth it" (as you say), forcing the classes > into an inheritance hierarchy doesn't seem Pythonic. (I may not have the > Python-fu to make such declarations, but I'll call 'em as I see 'em.) You're forgetting about virtual inheritance. > Also, x objects and y objects may be orderable homogeneously, but not > heterogeneously. I could impose a total order on sets of circles and > another on sets of squares without imposing an order on sets of both > circles and squares, and not be able to spell this under the inheritance > approach. Yes, that was what I explained at length. -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ 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
