text/html for XHTML+Math (Was Re: Mimetype: application/xhtml+xml -- add to validator?)

(For www-html, copy to www-math, follow-up to www-html)

On Tue, 29 May 2001 10:39:05 -0400 (EDT) I wrote to www-html@w3.org:
(see  http://lists.w3.org/Archives/Public/www-html/2001May/0088.html )

> The HTML WG could help here by tightening what needs to be at
> the top of an XHTML document when served as text/html.  (However,
> section 5 should still say "may", and Appendix C should remain
> informative, directed toward authors.)
> 
> For example, the *first non-blank line* should match one of the
> following regular expressions:
> 
> A)  '^ *<\?xml version='
> 
> B)  '<!DOCTYPE html .*//DTD XHTML'
> 
> C)  '<html xmlns='
> 
> For text/html if the first line does not match one of these, the user
> agent should assume classical HTML.  If the first line does match one
> of these, and the document is not conforming XML that makes sense as
> XHTML, the user agent should refuse it.

One might want to add another restriction for XHTML served as text/html:

When an XML document with root namespace http://www.w3.org/1999/xhtml
is served as text/html, there should be no internal declaration subset.
("Should" is not "must".)

Comments:

This restriction would be at variance with the markup I have seen in a
number of extant examples.  But most of these examples could be made
to meet this restriction (and be valid) after easy changes.  My
validation standard is Murray Altheim's "DTD XHTML 1.1 plus MathML 2.0",
available as
     http://www.w3.org/TR/MathML2/dtd/xhtml-math11-f.dtd .

Amaya appears to handle well documents correctly marked up for the
Altheim DTD whether served as text/html or as text/xml.  I am
impressed with the current Amaya as an XHTML+MathML navigator
and analyzer in regard to the flagging of errors.

William F. Hammond                   Dept. of Mathematics & Statistics
518-442-4625                                  The University at Albany
hammond@math.albany.edu                      Albany, NY 12222 (U.S.A.)
http://www.albany.edu/~hammond/                Dept. FAX: 518-442-4731

Never trust an SGML/XML vendor whose web page is not valid HTML.
And always support affirmative action on behalf of the finite places.

Received on Friday, 1 June 2001 21:37:11 UTC