On 3/12/14 9:32 AM, Jake Archibald wrote:
You're right, I was short on detail for that case.
img.src = foo;
var promise1 = img.loaded();
img.src = bar;
I expect promise1 to reject with an AbortError.
No, the case I'm worried about is when the first load has already
finished, you call loaded(), get a promise (already resolved), and then
a new load starts, and maybe finishes, before the promise has notified
things. So more like this:
var promise1;
img.onload = function() {
promise1 = img.loaded();
img.onload = null;
img.src = bar;
};
img.src = foo;
I realize no one would write actual code like this; the real-life use
case I'm worried about would be more like this:
// img is already loaded sometimes
// Would like to observe a new load
var promise1 = img.loaded(); // oops! This will be pre-resolved if
// we were already loaded, but otherwise
// will resolve with the new load we're
// about to start.
img.src = bar;
Is my concern making sense?
Images are particularly pernicious here because "img.src = bar" might
synchronously finish the load, even if it fires the load event async.
-Boris
