Re: Use of tags in header meta statements

On Tue, Jul 22, Dean Tiegs inscribed on the eternal scroll:

[I -ajf- had written, (specifically in regard to the character '<' in
attribute values:]

> > Well, I'm sure that this was legal in HTML: can you cite something
> > in the specifications which rules it out in XHTML? I don't see
> > anything listed in http://www.w3.org/TR/xhtml1/#diffs for example
> > which would rule-out this usage.
>
> The OP had specifically mentioned XHTML, so those were the syntax
> rules I was thinking of. (Actually I wasn't aware this was a
> difference from HTML, so I just learned something.)

And so, it seems, did I. How curious that they didn't seem to
point this up as a difference from HTML.

> Here's the citation:
>
> "The ampersand character (&) and the left angle bracket (<) may appear
> in their literal form only when used as markup delimiters, or within a
> comment, a processing instruction, or a CDATA section. If they are
> needed elsewhere, they must be escaped using either numeric character
> references or the strings '&amp;' and '&lt;' respectively."
>
> <http://www.w3.org/TR/REC-xml#syntax>

So it does, although that's somewhat narrative in nature. But this:

http://www.w3.org/TR/REC-xml#NT-AttValue

appears to clinch the deal, as far as XML is concerned. Does this
restriction carry-over to XHTML, and if so, why isn't it mentioned
here?: http://www.w3.org/TR/xhtml1/#h-4

> Note that attribute values are not listed as an exception. I wonder
> why it wasn't an exception? It causes no ambiguity, at least not for
> "<". The authors probably just wanted to minimize the exceptions and
> make the recommendation clear and simple.

Perhaps we could ask the XML group (x-posted).

[please feel free to narrow f'ups to whichever group you see fit.]

Alan J. Flavell