Re: CSS Selector Complexity : Working draft document

Francois Remy wrote:
> - Loop Complexity (or static complexity: time needed to find matching 
> elements at load time)

As I said in my other mail, this is not an interesting metric for a 
rendering engine (unless you're implementing querySelectorAll).  During 
load time the question that's asked (repeatedly) is not "which elements 
match this selector?" but "which selectors match this element, so that I 
can apply the relevant style rules?"

> - Update Complexity (number of times the matched elements can be 
> reevaluated * time it need)

My previous post broke this down in what I think is a more useful way.

>     * I voluntary excluded the optimizations that can be done by the UA 
> because they are probably not the same

But the space of possible optimizations is in fact key...  The question 
is always what the fastest smallest way is to implement something.

-Boris