Le 12/12/2011 16:40, Tom Van Cutsem a écrit : > (...) > > So in short I would prefer sensible defaults over error-throwing > missing fundamental traps. > I'd be interested in hearing others' thoughts about this. In how they are defined and used, virtual handlers are very much like the previous proxy design (hence the easy implementation of the previous design with them). The reason why one wants to get back to the fundamental/derived distinction is because she wants to define her own fundamental traps and that derived traps use her fundamental traps. It seems natural that derived traps fail if the fundamental trap they relied on has not been defined/does not exist. That's what happened in the previous design.
I don't think that the default you propose are a good idea, because it will make bugs harder to track. Object.getOwnPropertyDescriptor returning 'undefined' for any property does not sound like a good idea. Likewise for Object.getOwnPropertyNames returning [] systematically. Another idea would be to have no default for virtual handler fundamental trap and that the fundamental traps are the default direct proxies traps (forwarding to the target). For instance, if I want that all enumeration-related derived traps pass through my getOwnPropertyNames traps, I just define this trap in my handler which has all derived traps implemented on the VirtualHandler prototype. The object acts normally except when it comes to enumerating properties where my Object.getOwnPropertyNames is in control (as per the default virtual handler derived traps definitions). David _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
