The W3C CSS validator has a long story. A long, happy and sometimes sad story. Long because it represents MANY years of work for many people. Happy because zillions of people are using the W3C Validators, including the CSS one. Sad because the Consortium never really acknowledged the value, intellectual and potentially financial, of these tools. A while ago, my friends Yves Lafon, Karl Dubost and Olivier Théreaux all W3C staff complained about the complexity of the CSS Validator induced by CSS "levels". Because CSS has levels and not versions, the validator is in fact multiple validators in one single app and determining the "level" of a single CSS instance at parse time is difficult, very difficult.

Olivier is now leaving the World Wide Web Consortium for other skies and I was the first one (outside of W3C staff) to express real and repeated concerns about the fate of the CSS Validator. We discussed it during last W3C TPAC in Mandelieu. Elika Etemad did great gathering important people around one single table for a BOF session and we hope we secured a fate for the CSS Validator. I suggested myself a few areas of change for a "new" version of the CSS Validator:

  • first, whatever the zealots think of CSS "levels", my Microsoft friends (top of list here is Markus Mielke) are perfectly right saying we have here CSS versions and not levels. We should not care about CSS 1 any more. Granted, the froward-compatible grammar of CSS helps BUT what really matters is the grammar of CSS 1, CSS 2 and CSS 3. Implementing and maintaining all parsers is hard, time-consuming, and pretty useless for desktop and mobile browsers that never implement two different levels of CSS in the same engine.
  • the current validator's code is written in Java. I think that if a new validator is built, it should create a community of maintainers and be integrable easily in third-party apps. The speed of JavaScript improved so vastly and so many people are experts of that language that I think a validator written in JS now makes total sense.

So please, make sure to read Olivier's article about it, take some time to think about it, and leave a comment. Thanks.