[css3-cascade] Editorial comments

Hi,

Here are a few comments on the 2013-06-08 ED:


When listing "The precedence of the various origins", §4.2 should link 
to §4.2.1 and §4.2.2 to define origins and '!important', respectively.


§4.2.1. Cascading Origins should define that imported stylesheets have 
the same origin as the stylesheet that imported them.


Thorough the document, the word "origin" (especially when preceded by 
"same") should be disambiguated by linking either to §4.2.1 when it 
refers to cascading, and some other definition (maybe the WHATWG Fetch 
spec?) for the same-origin policy.

Similarly, "imported stylesheet" should link to the section defining 
'@import'.


With inheritance, the *computed* value of the parent becomes the 
*specified* value. This requires one of two things to keep the whole 
thing well-defined, although this is probably not a problem in practice:

1. The process of resolving a specified value into a computed value 
(which is specific to every property) must be idempotent.
2. Or §5.2 should say that the specified value becomes the computed 
value as-is if it was inherited from a computed value.

I’d prefer 2, as 1 is a burden for every other CSS spec.


In §5:

     Finally, the computed value is transformed to the actual value
     based on constraints of local environment.

s/computed/used/


The first two paragraphs of §5.2. "Finding the computed value" should be 
a non-normative design principle, since the process for finding the 
computed value is normatively defined by every property. Considerations 
of absolute vs. relative value can not always be generalized (an 
unitless number is absolute in 'opacity' but relative in 'line-height') 
and some relative values are not resolved until layout as used values.


Similarly in §5.3: the used value can differ from computed value more 
than just resolving remaining relative values. This process is specific 
to each property, and this spec should not generalize too much.


Cheers,
-- 
Simon Sapin

Received on Sunday, 9 June 2013 04:30:13 UTC