On 12/23/14 8:49 PM, Brendan Eich wrote:
On the DOM quirks point
Here's the thing. Ignoring for the moment the classes situation, it seems to me that for "DOM" stuff specifically we have three options:
1) Have all "DOM" prototype stuff be enumerable. This leaves us in a Conway's Law situation where whether stuff is enumerable or not depends on whether the spec is written by the W3C/WhatWG or TC39. That's where we've been for going on two decades now, but it still sucks.
2) Have some "DOM" stuff (whatever is currently shipping?) enumerable but new stuff not enumerable (basically introduce a [LegacyEnumerableProperties] or whatnot in Web IDL and sprinkle it on everything currently shipping). This still means we have inconsistent behavior, but now it's inconsistent in time as opposed to organizational structure. And it relies on UAs being able to make this change quickly for new APIs they add. Gecko can do that, but I can't speak for others.
3) Try to make all "DOM" stuff non-enumerable, dealing with compat issues by adding [LegacyEnumerableProperties] in the few cases where they arise. This risks landing us in the same place as #2 depending on how many interfaces need the annotation, plus compat fallout as we discover which interfaces need it. But it would maybe get us to the point where we don't have the Conway's Law problems, and it may well turn out that very few interfaces need the [LegacyEnumerableProperties] thing.
If I were doing green-field implementation of the DOM, of course, option 3 it would be, to match ES builtins....
Apart from all that, we've generally been aiming at converging Web IDL behavior on the behavior of ES6 classes as much as we can, and continue to do so. So if classes end up with stuff non-enumerable by default that would militate in favor of option 3 above. Which is great except for the possible compat fallout. I'm game for trying it, though, if other UAs are.
-Boris _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
