- From: Brad Kemper <brkemper@comcast.net>
- Date: Wed, 23 Jul 2008 10:58:58 -0700
- To: Boris Zbarsky <bzbarsky@MIT.EDU>
- Cc: www-style list <www-style@w3.org>
On Jul 23, 2008, at 10:43 AM, Boris Zbarsky <bzbarsky@MIT.EDU> wrote: > Brad Kemper wrote: >> In fact, I do have an example of that, and it does not seem slow at >> all > > "slow" is a relative concept. Handling DOM mutations in this > document is slower than if the '+' combinator were not used. It's > still fast compared to human reaction times. > > Of course your page is two orders of magnitude smaller than typical > "commercial" webpages, and about 4 orders of magnitude smaller than > typical "big" webpages where algorithmic complexity issues _really_ > start to kick in. > > Seriously, users want arbitrarily sized HTML documents handled in a > "non-laggy" way. In practice that means that nothing should ever > take longer than 200ms, and continuous updates need to happen every > 20ms or more often. If it takes you longer than 20ms to respond to > arbitrary DOM changes for an arbitrary HTML document, you will be > perceived as "slow". > > -Boris And yet implementors impletent adjacency selectors but not ":has- child", even though the issues seem to the same.
Received on Wednesday, 23 July 2008 17:59:59 UTC