Re: [CSS21] Lack of version control for content

On Saturday, August 27, 2005, 9:50:48 PM, Henri wrote:

HS> On Aug 25, 2005, at 16:44, Chris Lilley wrote:

>> Experience with the CSS validator shows that the lack of version
>> identification is a significant problem for managing CSS content; there
>> is no way to indicate to which of the multiple, changing, overlapping
>> versions of CSS the stye sheet is attempting to comply.

HS> Why is it important for a style sheet to tell what it attempts to 
HS> comply with?

So that it can be validated.
So that an author can chose which version to output.

HS>  Isn't it more interesting to ask "Does this style sheet
HS> comply with CSS 2.1?"? In that case, it is the user of the validator 
HS> who should give the desired CSS version as additional input.

HS> Compare this with how DTD validation and RELAX NG validation work. I 
HS> think the RELAX NG model with the validation process taking two 
HS> independent inputs (the schema and the document) answers more useful 
HS> question than the DTD model in which the document provides its own 
HS> schema.

An interesting comparison, but flawed. Removing the link to the actual
schema is a good thing - but CSS has never had such a link. RelaxNG
schemas can hook into a version attribute, for example - but CSS doesn't
have one of those either.

If the CSS WG does not consider that validation of CSS stylesheets is
appropriate, please explain that to the CSS validator folks. Currently,
the W3C CSS validator seems to assume CSS 2.0, so it complains about
orange and fails to complain about properties in CSS2 and not in CSS
2.1, for example.

Similarly, if someone is using CSS MP, the validator woudl fail to warn
about using properties outside that profile. Validation is useful.
Adding an @-rule would be an easy way to indicate to which specification
a given style-sheet conforms.

-- 
 Chris Lilley                    mailto:chris@w3.org
 Chair, W3C SVG Working Group
 W3C Graphics Activity Lead

Received on Tuesday, 30 August 2005 01:26:14 UTC