- From: Dave Raggett <dsr@w3.org>
- Date: Mon, 04 Jul 2011 19:01:36 +0100
- To: Olli@pettay.fi
- CC: Olli Pettay <Olli.Pettay@helsinki.fi>, Ojan Vafai <ojan@chromium.org>, Boris Zbarsky <bzbarsky@mit.edu>, public-webapps@w3.org
On 04/07/11 17:57, Olli Pettay wrote: > Mutation listener could easily > implement old/new value handling itself, especially if it knows which > attributes it is interested in. How exactly would the listener know the previous state? For a concurrent editing app, it is important to be able to describe changes reversibly so that you can revert the DOM when a given local edit isn't accepted, or you need to revert before applying accepted changes from other clients. I have been able to get this to work fine with the existing mutation events. Of course, I avoid changing the DOM within a mutation event listener, but it is easy to defer such changes by a call to setTimeout, e.g. with a time of zero. I would be quite happy for the browser to throw an exception when a mutation event listener tries to call an unsafe API, as this way developers would rapidly learn of their mistake and switch to better practices. -- Dave Raggett<dsr@w3.org> http://www.w3.org/People/Raggett
Received on Monday, 4 July 2011 18:02:16 UTC