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- Date: Thu, 06 Mar 2014 07:31:20 +0000
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https://www.w3.org/Bugs/Public/show_bug.cgi?id=24872 Hayato Ito <hayato@chromium.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |hayato@chromium.org --- Comment #4 from Hayato Ito <hayato@chromium.org> --- (In reply to Jonas Sicking from comment #1) > My concern with this is that it means that anytime that a node is inserted > anywhere, we need to recheck the insertion-point for all of its siblings. > > Adding William who can comment more on the performance implications of this. That is not specific to the ':first-of-type'. We have to recalculate distributions whenever a node is inserted whether matching criteria has ':first-of-type' or not. (In reply to Ryosuke Niwa from comment #3) > (In reply to Jonas Sicking from comment #1) > > My concern with this is that it means that anytime that a node is inserted > > anywhere, we need to recheck the insertion-point for all of its siblings. > > Same concern here. The problem with :first-of-type is that it involves > walking previous siblings to check this condition when multiple children are > inserted via document fragments. Right. I guess this is one of the pseudo classes which is difficult to implement without performance impact. In general, we need *virtual siblings traversal* for Tree-Structural pseudo-classes. http://dev.w3.org/csswg/selectors4/#structural-pseudos For reference: Chromium side bug is here: https://code.google.com/p/chromium/issues/detail?id=343332 In blink, we already supported some of pseudo classes. To implement these in blink, we (especially shinyak@chromium.org) had to use a technique of C++'s template so that we could overcome perf concern. There is a technical difficulty. > > (In reply to Domenic Denicola from comment #2) > > I would really much prefer if there was an imperative way to add content; > > the <content> element is un-ergonomic and very hard to use in a sensible > > way. I am hearing this feedback from multiple developers as I try to show > > them shadow DOM. > > > > I know there is already an open issue for this (bug 18429) but I thought it > > was relevant since this bug seems to be about putting lipstick on the > > <content> pig, whereas we could instead try to create something non-pig-like. > > Yes. In fact, we (Apple) would argue that we should implement the imperative > API first. -- You are receiving this mail because: You are the QA Contact for the bug.
Received on Thursday, 6 March 2014 07:31:25 UTC