Re: min-font-size

>On further thought, I guess that under constrained stylesheets won't be a
>problem - a default value for the value triplet is always well defined in
>CSS (but are they meaningful?). On the other hand, I can't tell off the top
>of my head whether allowing each numeric attribute to have a minimal/maximal
>value means that stylesheets can become over constrained. Maybe someone who
>knows the specs better can comment on this? Is there already a coherent way
>to deal with conflicting attributes?

   My gut feeling is that this won't be a major problem.  Fortunately,
there's more than just my gut to go on here:

     http://www.utoronto.ca/ian/www8/ccss-uwtr.pdf

This is the PDF version of a talk given at WWW8 in Toronto, titled
"Constraint Cascading Style Sheets."  The syntax presented is frankly
pretty ugly, but I spoke with the presenter (Greg Badros) after his talk
and he said, in effect, "I don't care two figs about the syntax.  CSS just
needs constraints.  This is a well-defined problem, and there's no reason
not to add constraints."
   That's paraphrased, of course, but it's basically where he's coming
from.  According to Greg, there is an entire field of study (although I
don't know how big) devoted to studying constraint systems, and to
developing algorithms which can express/solve any constraint situation.
Greg claims that adding this sort of thing is not an issue, becuase the
theoretical work's been done already.  The CSS WG just needs to agree that
it should be added to CSS, work out the syntax, and go from there.
   Just a few weeks before hearing Greg's talk, actually, I proposed a
system which works something like this:

     P {font-size: 8pt+ 9pt 12pt-}

That translates to, "set paragraph 'font-size' to be 8pt or greater, and
12pt or less, with 9pt the preferred size."
   I didn't use the word "constraint" in my proposal, but the same idea is
there.  I intend to rewrite my proposal using a slightly more formal
approach (and a new title), and submit it to the WG for consideration in
the near future.  I hope the above paper will shed some light on the
inheritance conflict resolution issues, or at least fuel a spirited
discussion.

--
Eric A. Meyer  -  eam3@po.cwru.edu  -  http://www.cwru.edu/home/eam3.html
 Editor, Style Sheets Reference Guide  http://style.webreview.com/
 Coordinator, CSS1 Test Suite          http://www.w3.org/Style/CSS/Test/
 Member, WSP CSS Technical Committee   http://www.webstandards.org/

Received on Monday, 19 July 1999 12:27:06 UTC