- From: Adam Klein <adamk@chromium.org>
- Date: Fri, 15 Jun 2012 16:36:29 -0700
- To: WebApps WG <public-webapps@w3.org>
- Cc: Olli@pettay.fi, Rafael Weinstein <rafaelw@chromium.org>
Received on Friday, 15 June 2012 23:36:58 UTC
Re-sending from correct address: On Fri, Jun 15, 2012 at 4:35 PM, Adam Klein <adamk@google.com> wrote: > This code alerts in Firefox but not in Chrome: > > <!DOCTYPE html> > <body> > <script> > var observer = new MutationObserver(function(r) { > alert(r); > }); > observer.observe(document.body, {childList: true, subtree: true}); > </script> > <p>Hello, World</p> > </body> > > In WebKit's implementation, we had assumed that MutationObservers were > meant to observe changes after page load (and I personally thought that > we'd specced it that way, by putting it in DOM4, not HTML). But it seems > the Mozilla implementors made a different assumption. But what should > happen? > > IMHO, it may not be worth the gain may not be worth the possible > performance degradation. If script wants to find out what the parser put on > the page, it should wait for DOMContentLoaded. But I can imagine a use case > where script might want to find out about the parser's work during load. > > In any case, we should try to come to a decision about this, since this > seems to be the one major divergence between the existent implementations > of MutationObservers. > > Thoughts? > > - Adam >
Received on Friday, 15 June 2012 23:36:58 UTC