W3C home > Mailing lists > Public > www-html@w3.org > February 2000

Re: Notations are useful

From: Murray Altheim <altheim@eng.sun.com>
Date: Sat, 05 Feb 2000 03:15:22 -0800
Message-ID: <389C064A.E14CC8E3@eng.sun.com>
To: Arjun Ray <aray@q2.net>
CC: www-html@w3.org
Arjun Ray wrote:
> On Mon, 31 Jan 2000, Russell Steven Shawn O'Connor wrote:
> > I agree that this would be ideal, but I have an itch telling me
> > that the best solution somehow lies with the use of NOTATION.
> Unfortunately, there seems to be a vicious circle between the lack of
> knowledge regarding Notations and their neglect.  Since not many
> people know what they're for, not many people are likely to use them,
> and if they're not used, not many people are likely to find out what
> problems they solve.  In line with this, the HTML DTDs don't use any,
> and it seems they may never.

Well, only because the part we need in XHTML is missing in XML. For now,

> Unfortunately, the XML 1.0 spec missed the boat on a significant
> innovation in the WebSGML TC (besides, of course, severely limiting
> the utility of Notations by disallowing data attributes.)  This is a
> new category of declared value for attributes called DATA.  Its
> purpose is to signify the fact that the attribute value is subject to
> a notation (i.e. a structure or grammar or syntax, defined elsewhere)
> For instance, something like this isn't really meaningful:
>    <!ATTLIST ...
>          href   CDATA    #IMPLIED
>          ... >
> and hiding the CDATA declared value in a suggestively named PE, like
> %URI.datatype; - as in the new xHTML 1.1 DTD [1] - is really just all
> handwaving too, since the *essential* information is inside a comment:

Only because that is our only option. At least now they're regularized.

> It's interesting to note that there is no provision for this facility
> in the XSchema specs (where, if you want a new "datatype", you have to
> go through an elaborate definition procedure - you can't simply
> reference an external spec.)
> Looks like a whole bunch of stuff will have to be reinvented...

As you know, I'm quite interested in use of WebSGML's 'DATA' attributes
feature, and have lobbied within the HTML WG to begin work on figuring
out exactly what all of the data types (ie., notations) currently used
in XHTML are, and come to some determination on how they can be declared
in a way that is the same between XHTML DTDs and Schemas. We're kinda
in uncharted territory here since this would require a change to XML in
order to really use it, but it's nevertheless not wasted activity. We
need to understand better the data types we're using anyway, esp. as
we move into schemas for XHTML. If the 'DATA' attributes feature proves
that valuable, then perhaps we can lobby for its inclusion in a future
version of XML.

In line with a 'me too' comment: write up a proposal, submit it to the 
W3C Core WG. They may ignore you, but I think there's enough expertise
in the group to seriously consider an addition like this, especially as
it cuts across DTD and Schema boundaries when one considers the existence
of the Schema Datatypes WD.
Your input on architectural forms wasn't wasted. (Thanks!) I don't in the
end know what will happen with it, but I gave a short presentation on the 
functionality of AFs at the last F2F meeting, so that's progress in some
people's book.


Murray Altheim                                   <mailto:altheim@sonic.net>
Member of Technical Staff, Tools Development & Support
Sun Microsystems, Inc. MS MPK17-102
1601 Willow Rd., Menlo Park, California 94025  <mailto:altheim@eng.sun.com>

   the honey bee is sad and cross and wicked as a weasel
   and when she perches on you boss she leaves a little measle -- archy
Received on Saturday, 5 February 2000 06:17:07 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 7 January 2015 15:05:52 UTC