On Oct 18, 2009, at 4:14 AM, Jonas Sicking wrote:
On Sun, Oct 18, 2009 at 12:12 AM, Doug Schepers <schep...@w3.org>
wrote:
So, rather than dwell on an admittedly imperfect spec, I personally
suggest
that we urge WebKit developers to implement .children
and .children.length,
in the anticipation that this will be in a future spec but can be
useful to
authors today.
They already do. Which casts some amount of doubt on Maciejs argument
that it was too performance heavy to implement in WebKit. :)
What I said way back in the day (about childElements) was this:
"I suggest leaving this out, because it's not possible to implement
both next/previous and indexed access in a way that is efficient for
all cases (it's possible to make it fast for most cases but pretty
challenging to make it efficient for all). This is especially bad with
a live list and an element whose contents may be changing while you
are iterating. If all you care about is looping through once, writing
the loop with nextElementSibling is not significantly harder than
indexing a list."
I stand by that remark. It is indeed hard to get both indexed and
previous/next access efficient in all cases. Of course, we are not
going to let that stop us from interoperating with de facto standards,
and we do our best (as for other kinds of NodeLists and
HTMLCollections), but I'd rather not have new APIs follow this pattern.
In this particular case, I think anything that's implemented in all of
the major browser engines should be an official standard, not just de
facto.
Regards,
Maciej
