[whatwg] prefilling select

[Olav Junker Kjær]

A few questions to prefilling select elements (Section 6.1):

I understand that when a selected element with a data attribute is 
parsed, the data document should be immediately fetched, and the 
select-element is prefilled before the parser continues. This might give 
a slight pause in page loading, but it's not different form how script 
src elements are loadet. The upside is that it enables us to manipulate 
the data in script immediatly after the element, instead of having to 
wait for some event to fire.

However:
"If a select element has its data attribute manipulated via the DOM, 
then that should immediately begin the prefilling process too. However, 
any currently executing script must be guaranteed to run to completion 
before the changes required by the process take effect."

So in this case, the data document(s) are loaded asynchronously, and 
several data requests might be running at the same time, though the 
resulting documents should be processed in the same order they were 
initiated.

Why the difference in these two cases? In the second case, we need some 
kind of event to notify when all pending requests has been processed, to 
trigger form prefilling and the onload event. Why dont use the same 
mechanism in the first case then, and have the page load faster?

Another question: isn't it a bit confusing to use a property to load 
data into the control, when the effect of loading (may be) cumulative? 
Usually attributes setting is idempotent. Maybe it would be more natural 
to use a method called loadData(uri) or something like that.

Olav Junker Kjær