Re: CSS and XSL properties - relationship

Christopher R. Maden writes:
> [Simon St. Laurent]
> >I'd love to see a clear statement of how exactly the relationship between
> >CSS and XSL is supposed to work.  Are both still independent ventures?
> >It seems like it might be easier to develop a core formatting model group,
> >which then gets expressed through CSS and XSL processing, than to have two
> >groups working independently, but you never know.

Everything we (i.e., W3C, these two mailing lists, and everybody else
who helps develop technology for the Web) do is based on our best
guesses about the future of the Web. Our expectations change all the
time and projects get retargeted or abandoned as a result, but let me
try to put in words what I currently think about the roles XSL and CSS
should or can play. This is not an official statement, just my
personal assessment of the current situation. I have above all tried
to be clear, as Simon St. Laurent requested.

I think the relationship between XSL(FO) and CSS is best expressed by
their respective goals. If we leave XSLT apart for the moment (since
it can be used with CSS as well as with XSL Formatting Objects), then
CSS is the 80% solution, XSL(FO) the high-end tool for the next 15%.
The remaining 5% needs real programming.

On the scale between capabilities, usability, and ease of
implementation, CSS stresses usability, then implementation, and is
willing to limit its powers. XSL is the reverse. In other words: CSS
should be accessible to everybody, XSL should be able to do almost

A corrollary of that is that XSL should in principle be able to do
everything CSS can, but it is not a requirement that translating a CSS
stylesheet to an XSL one must be "easy" in some sense of the word.

So the result is that they are largely independent. We try to avoid
unnecessary differences (in property names, e.g.), but the two
languages are sufficiently different and targeted at sufficiently
different audiences that the bulk of the work for each is better done
in separate working groups.

> There is a core formatting group, and there has been since mid- to late '98
> at least (I don't remember when exactly it started).  Bert Bos, Martin
> Dürst, Steve Zilles, and Stephen Deach are among the members.

That's not quite right. There is no core formatting group. We would
have announced it on otherwise. I
assume you refer to the shared mailing list to which all members of
the CSS&FP WG and the XSL WG are ex-officio subscribed. That mailing
list is used for matters that affect both groups. It's just a way to
manage e-mail streams and avoid cross-postings, not a separate group.

The two groups have in fact discussed several times whether
reorganizing the work in more, fewer or different working groups would
make the development of CSS and XSL easier, but the conclusion is
still that one working group each is best. Every other organization,
except a single working group, would lead to more rather than less
traffic between the groups. And for a single working group the work is
just too big and too diverse.

  Bert Bos                                ( W 3 C )                              W3C/INRIA                             2004 Rt des Lucioles / BP 93
  +33 (0)4 92 38 76 92            06902 Sophia Antipolis Cedex, France

Received on Tuesday, 19 October 1999 14:38:38 UTC