Posted by David Dorward on 05/31/06 21:31

Toby Inkster wrote:

> It says no such thing. Section 5.1 states that documents meeting
> appendix C may be served as "text/html", but it does not state the
> converse: that documents not meeting appendic C guidelines must
> not be served as "text/html".

RFC 2854 says:

In addition, XHTML 1 defines a profile of use of XHTML which is compatible
with HTML 4.01 and which may also be labeled as text/html.

XHTML 1.0 5.1 says:

XHTML Documents which follow the guidelines set forth in Appendix C,
"HTML Compatibility Guidelines" may be labeled with the Internet Media
Type "text/html" [RFC2854], as they are compatible with most HTML
browsers.

So Appendix C documents may be served as text/html.

It also says:

Those documents, and any other document conforming to this specification,
may also be labeled with the Internet Media Type "application/xhtml+xml"
as defined in [RFC3236].

So Appendix C and non-Appendix C documents may be served as
application/xhtml+xml.

It also says:

For further information on using media types with XHTML, see the
informative note [XHTMLMIME].

Which says:

XHTML 1.0 (other) SHOULD NOT [be served as] text/html.

OK, so "SHOULD NOT" isn't as strong as "must not" and means that there "may
exist valid reasons in particular circumstances when the particular
behavior is acceptable or even useful, but the full implications should be
understood and the case carefully weighed before implementing any behavior
described with this label", but I have a hard time spotting any
circumstance where "breaking in IE" would be desirable, and the RFC and
XHTML Recommendation themselves don't at any point allow it.

Of course, for even more fun you can throw in the introduction to Appendix C
which says:

Note that this recommendation does not ... define the meaning of the
Internet Media Type text/html. For these definitions, see ... [RFC2854].

Which means that XHTML 1.0 says to see Appendix C, Appendix C says to see
RFC 2854, and RFC 2854 says to see XHTML 1.0, and you end up going around
in an infinite loop which never ends up at a point where you find out any
circumstances under which XHTML 1.0 is allowed to be served as text/html.

Just one more reason to stick to HTML 4.01 on the client side if you are
writing text/html webpages.

--
David Dorward <http://blog.dorward.me.uk/> <http://dorward.me.uk/>
Home is where the ~/.bashrc is

[Back to original message]