- From: Anne van Kesteren <annevk@opera.com>
- Date: Fri, 12 Feb 2010 14:05:24 +0100
- To: "Maciej Stachowiak" <mjs@apple.com>
- Cc: "Anton Muhin" <antonm@chromium.org>, public-webapps@w3.org
On Fri, 12 Feb 2010 12:51:03 +0100, Maciej Stachowiak <mjs@apple.com> wrote: > On Feb 12, 2010, at 3:47 AM, Maciej Stachowiak wrote: >> On Feb 12, 2010, at 3:19 AM, Anne van Kesteren wrote: >>> On Fri, 22 Jan 2010 14:11:40 +0100, Anton Muhin <antonm@chromium.org> >>> wrote: >>>> Is it possible to allow caching for those cases? Firefox caches those >>>> node lists for a long time (Maciej found the related bug >>>> https://bugzilla.mozilla.org/show_bug.cgi?id=140758). IE8 caches as >>>> well. Opera, Safari and Chrome do not. >>> >>> Sorry for the somewhat late reply. We'd prefer not to change the >>> specification here and keep the requirement. We're afraid of potential >>> hard to detect incompatibility bugs if you sometimes cache and >>> sometimes don't. We're also not convinced that you cannot get the >>> performance win by other means. >> >> Since Firefox and IE both cache, how would it create compatibility bugs >> for other browsers to do so as well? I think we should remove the >> requirement unless Firefox and IE are willing to change their >> implementations. I would hope they fix their bugs in due course, yes. Specifically leaving the behavior undefined seems like a bad idea. We know that from other areas. > In addition, I should mention that likely the only observable difference > is in setting custom ("expando") properties. If you make two equivalent > requests for a NodeList, setting a property on one will show up on the > other only in the case where there was caching. However, I think use of > expando properties on NodeLists is unlikely. Sacrificing a lot of > performance for a marginal hypothetical improvement in predictability of > behavior does not seem like a good tradeoff. Is it really a lot of performance? Our developers are not that convinced. Also it has been suggested to me that just-in-time optimizations might not work well if different users start polluting the same object (if nodelists are shared). -- Anne van Kesteren http://annevankesteren.nl/
Received on Friday, 12 February 2010 13:06:08 UTC