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Re: text/html for html and xhtml

From: William F Hammond <hammond@csc.albany.edu>
Date: Mon, 21 Apr 2008 19:25:11 -0400
To: public-html@w3.org, www-math@w3.org, www-svg@w3.org
Message-ID: <i7ve2avlig.fsf@hilbert.math.albany.edu>

Boris Zbarsky <bzbarsky@MIT.EDU> writes:

> William F Hammond wrote:
>>>> 1.  Many search engines appear not to look at application/xhtml+xml.
>>> That seems like a much simpler thing to fix in search engines than in
>>> the specification and UAs, to be honest.
>> Technically yes, but politically no.
>
> Why, exactly?

I already explained that.

> Have you actually brought this up with any search engine providers?

It was mentioned in the parent of this cross-posted thread;
see http://lists.w3.org/Archives/Public/www-math/2008Mar/0042.html

> Uh... We're talking about a tradeoff between complexity in all
> shipping HTML parsers and complexity in search engines.  Content
> providers don't even enter the picture here.

Yes they do; it's been a consistent theme over the years since 2001
in www-math@w3.org.

> Not to mention that you never answered my concerns about ambiguous
> doctype detection.

But I did; and I said in the worst case new specs could provide
an easy-for-browsers method, going forward, to flag the distinction.

>> Long term those
>> mimetypes might better be handled by XML triage agents than by web
>> browsers.
>
> I'm not sure where the conclusion follows from, since right now
> browsers handle those types just fine if the content is something they
> know what to do with.

The world of xml has two parts: (1) documents for human reading
and (2) electronic data.  Not every xml instance is suitable for
browsers.

> ...
> My point is that the application/xhtml+xml vs application/xml
> distinction is useful in providing extra information (that the XML
> document is in fact expected to be XHTML), 

to be XHTML and not be random EDI stuff largely unsuitable for
display

> but by no means necessary to render XHTML.
> Further, as things stand an application/xhtml+xml
> document that contains MathML is actually invalid (per the rules about
> what content you can label as application/xhtml+xml).

David Carlisle has referred you to RFC 3236 for this.
There are also these items from W3C:
http://www.w3.org/TR/xhtml-media-types/
http://www.w3.org/MarkUp/2004/xhtml-faq
And see the hooks
<XHTML_1.1_MathML_2> and <XHTML_1.1_MathML_2_SVG_1.1>
in
http://dev.w3.org/cvsweb/validator/htdocs/config/types.conf?rev=1.12

Within the last few years the IE+Mathplayer folk have indicated
a preference for application/xhtml+xml.  As David Carlisle explained,
when such content is suitably served, it's not necessary for the
xslt object known as UMSS to be involved so long as the only mathml
is presentation mathml.  Moreover, it is also the case that somebody
from the Opera community indicated that the presence of the UMSS was
a problem for their work with math and css.

Currently application/xhtml+xml is the unique mimetype where
inter-operability exists for xhtml+mathml.

                                    -- Bill
Received on Monday, 21 April 2008 23:26:01 GMT

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