- From: David Flanagan <dflanagan@mozilla.com>
- Date: Fri, 01 Jul 2011 15:25:22 -0700
- To: Olli@pettay.fi
- CC: Olli Pettay <Olli.Pettay@helsinki.fi>, Rafael Weinstein <rafaelw@google.com>, Boris Zbarsky <bzbarsky@mit.edu>, public-webapps <public-webapps@w3.org>
On 7/1/11 3:06 PM, Olli Pettay wrote: > On 07/02/2011 12:59 AM, David Flanagan wrote: >> >> But, and I think this is an interesting but, what happens if a node is >> removed from the document, has its attributes or data or children >> changed and is then re-inserted into the document? If the node has no >> parent when it is changed, no mutation events will be generated, will >> they? > Sure they are. If the node has listeners, they will get called. > I'm assuming the listeners are further up the tree. To give a concrete example, to a mutation event listener (under Rafael's proposal, but maybe yours, too?) on the document, these two sequences of operations will be indistinguishable: // Generates one event for removing the title text from the <head> and another for // inserting it into the <body>. (Assume document.head.firstChild.firstChild is the text node inside // the <title> tag. document.body.appendChild(document.head.firstChild.firstChild); // Here we generate the same sequence of mutation events var titletext = document.head.firstChild.firstChild. titletext.parentNode.removeChild(titletext); // Generates a remove event titletext.data = "foobar"; // Generates a mutation event no one sees document.body.appendChild(titletext); // Generates an insert event I claim that it is useful to be able to distinguish these two cases with some sort of move event. If moves are treated as remove/insert pairs, then listeners have to assume that arbitrary changes could have taken place between the two. David
Received on Friday, 1 July 2011 22:26:00 UTC