On 7/5/11 4:25 PM, Aryeh Gregor wrote:
Maybe we don't want to give authors the ability to suspend mutation
events at all, though, sure.
Indeed.
It would also be a good way to deoptimize jits (e.g. you have to actually
_have_ the function around to detect when it "exits", so if your jit does
inlining you have to turn that off or instrument it for functions that
contain that call) without realizing it.
You'd have to add some extra instructions at every exit point of the
function when you inline it, yes. You'd have to do the same if you
don't inline it, too.
Not necessarily; in the non-inlining case, removing the stack frame can
just automatically do the work.
Unless you tail-recurse, in which case you don't remove the stackframe,
of course....
This doesn't seem prohibitive by itself, particularly given that functions
where you'd use this will be doing
multiple DOM modifications.
Maybe. Maybe not.
As far as I can see, the page can get repainted (meaning visually
updated in response to DOM changes, not sure if my terminology is
correct) in most browsers even when regular old scripts are running.
When I write tests in JavaScript that do many seconds of DOM
manipulation and add results to a table as they go, IE/Firefox/Opera
all visibly start displaying results long before the tests are done
running.
Unless your tests are explicitly yielding via setTimeout, that's quite
odd in at least the Firefox case.
But they probably don't want to do this in the middle of
execCommand() execution, when the DOM is in some transient state that
will display oddly for a moment and then flicker away.
It's not "a moment" if something happens in the middle of the
execCommand that takes a while to complete and hits the network in the
process.
The goal would be to not have such things happening in the middle of
execCommand.
So if halfway through the mutation listeners for an execCommand one of the
listeners does a showModalDialog(), should the page the dialog comes from
stop painting until that dialog is dismissed?
I wouldn't say so, no. HTML5 seems to say that things like that
should cause the UA to "pause", and the definition of that includes
updating the rendering:
http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#pause
OK, that much I agree on. But then I can't tell what you're proposing.
-Boris
