- From: <bugzilla@jessica.w3.org>
- Date: Thu, 06 Mar 2014 15:56:27 +0000
- To: public-webapps-bugzilla@w3.org
https://www.w3.org/Bugs/Public/show_bug.cgi?id=24872 --- Comment #5 from Ryosuke Niwa <rniwa@webkit.org> --- (In reply to Hayato Ito from comment #4) > (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 I don't think we should be supporting these pseudo selectors in the level 1 specification when we could easily support the use case by adding a simple imperative API for it given the performance impact. In fact, such an imperative API would support more use cases such as an element that picks a random child element upon click. I'd go as far as to say we wouldn't implement this even if it were in the spec. -- You are receiving this mail because: You are the QA Contact for the bug.
Received on Thursday, 6 March 2014 15:56:31 UTC