[whatwg] Proposal: Adding methods like getElementById and getElementsByTagName to DocumentFragments

[Boris Zbarsky]

On 10/22/13 7:00 AM, Anne van Kesteren wrote:
> So do you think we should add getElementById() to ParentNode in DOM?

I actually do, yes.

> It seems the advantages are that we can optimize it better than
> querySelector() because there is no selector parsing.

This, in my mind, is a somewhat minor advantage.

> And because there is no selector parsing, you can simply pass the value of an
> element's id attribute rather than escaping said value using CSS
> escape rules.

Right.  More importantly, you don't have to even understand that there 
are CSS escaping rules involved, which is a bigger hurdle than doing the 
escaping once you've understood that part....

> What it seems we lack is a clear need for either

Where by "either" you mean lack of a need for passing without escaping 
first?  See above.

> but if the cost of
> implementing it is low, maybe it's worth it?

The way I see it, UAs already have to implement 
SVGSVGElement.prototype.getElementById.  I suspect that in practice the 
same implementation can be used for any Element or DocumentFragment, so 
the cost of implementing is in fact quite low.

-Boris