> But doesn't CLASS have enforced values in the case of the <NOTE>
> element? Unless I misunderstand (this from [1]), NOTE has some
> predefined CLASSes with suggested renderings, i.e. WARNING, NOTE,
> and CAUTION.
>
> [1] http://www.ing.unipi.it/Html/html3_ietf_draft/notes.html
The pertinent text is:
CLASS
This a space separated list of SGML NAME tokens and is used to
subclass tag names. By convention, the class names are interpreted
hierarchically, with the most general class on the left and the most
specific on the right, where classes are separated by a period. The
CLASS attribute is most commonly used to attach a different style to
some element, but it is recommended that where practical class
names should be picked on the basis of the element's semantics, as
this will permit other uses, such as restricting search through
documents by matching on element class names. Apart from the
values suggested above, the conventions for choosing class names
are outside the scope of this specification.
So, no, they are not enforced. They (WARNING, CAUTION and NOTE)
are "suggested values", and as indicated, the means by which other
values are chosen are outside the scope of the specification. Most of
the element tags have this caveat at the end of the CLASS attribute
description. I wouldn't be suprised to eventually see something along
these lines being made possible by the stylesheets specification, for NOTE
NOTE.warning : image.src = some_url
NOTE.warning : image.glyph = predefined_glyph_image
To allow the exact image which is displayed to be suggested by the
document author.
Also bear in mind, that the mechanism by which the stylesheets allow
you to identify individual instances of elements is by using the CLASS
attribute. So, if you wanted CLASS="2dpie" to represent a 2D Pie chart,
I could certainly set certain style options for /all/ the <TABLE
CLASS="2dpie"> in a given document, but if I wanted to have, say, one 2d pie
chart with red, green and yellow sections, and in the same document,
another 2d pie chart, with blue, orange, mauve and yellow sections
and to have the third segment "exploded", I couldn't (unless the
colour and other information was fudged into the markup, which is
precisely what we've been trying to avoid!)
Ciao,
Chris
-- Chris.Tilbury@estate.warwick.ac.uk; MIME Mail Welcome Tel: +44 1203 523523x2665, Fax: +44 1203 524444