[csswg-drafts] [css-functions] Shouldn't the index of functions include `url()`?

praveenpuglia has just created a new issue for 
https://github.com/w3c/csswg-drafts:

== [css-functions] Shouldn't the index of functions include `url()`? 
==
I am looking at the CSS Indexes, 
[Functions](https://drafts.csswg.org/indexes/#functions) section and I
 realized the `url()` function isn't mentioned there. Is this 
deliberate or am I missing something?

Looking at this 
[example](https://www.w3.org/TR/css3-values/#functional-notations) it 
feels like it should be part of it.


Please view or discuss this issue at 
https://github.com/w3c/csswg-drafts/issues/1014 using your GitHub 
account