Cameron McCormack wrote:
I wondered that myself, but it would help the case where script authors want to mess about with the prototypes of various objects. Perhaps it doesn’t need to be specified exactly, but with enough fixed down such that you could reliably assign to HTMLElement.prototype.appendChild and expect it to affect your div element.
Agreed. The fact that it doesn't in Gecko is not exactly desirable, and is not a purposeful decision; it's a side-effect of how the general system for reflecting C++ into ECMAScript handles multiple interfaces implemented on a single ECMA object.
How about for Mozilla, assuming something “sensible” was specified that allowed script authors to know in which prototype object methods from a particular interface are to be found so that they can overwrite them?
Basically, the only way this would change in Mozilla is if Mozilla completely changes how C++ objects are reflected into ECMAScript for DOM objects.
On the bright side, there are plans to do just that in the next several years, so I'd say that there's a good chance that a sensible spec here would get implemented in Gecko. I can't commit to that on my own, though. I'll ask the folks who might be able to to chime in.
-Boris
