Clarification of allowed content in <title>

Hello www-html-editor,

This is more a point for clarification than an error in the HTML 4.01
spec, but at 
<URL:http://www.w3.org/TR/html40/struct/global.html#h-7.4.2> the comment
"Titles may contain character entities (for accented characters, special
characters, 
etc.), but may not contain other markup." has been misconstrued by some
as
allowing comments in the title as they are not specifically excluded.
It is not necessarily apparent to the beginning reader of the spec that
HTML commnets *are* markup; to the beginner comments may easily look
like
another category altogether. More experienced readers have misread the
spec
in the same way.

See the "HTML comments in <title> elements - valid or not?" thread at 
<URL:http://lists.w3.org/Archives/Public/www-html/1999Nov/> and the
Mozilla bug 
report at <URL:http://bugzilla.mozilla.org/show_bug.cgi?id=13015> for
background.

A related issue: I know that the spec clearly states, somewhere, that
the DTD does not encompass the entire specification, and that in fact
the spec includes constraints that are inexpresible in the DTD.
I was not able to find it, easily, this evening.  The best I could find,
under
<URL:http://www.w3.org/TR/html40/intro/sgmltut.html#h-3.1>, was
"Each markup language defined in SGML is called an SGML application. An
SGML application is generally characterized by: ...
3. A specification that describes the semantics to be ascribed to the
markup. This specification also imposes syntax restrictions that cannot
be expressed within the 
DTD. ..." - which does not quite get around to saying that this applies
to HTML.
         
Suggested enhancements to the specification:

1. Change the sentence beginning "Titles may contain character entities
(for accented characters, special characters, etc.), but may not contain
other markup." to read
"Titles may contain character entities (for accented characters, special
characters, 
etc.), but may not contain comments or any other markup."  - at 
<URL:http://www.w3.org/TR/html40/struct/global.html#h-7.4.2>

2. Add a sentence, "Comments are HTML markup." or otherwise express this
concept at <URL:http://www.w3.org/TR/html40/intro/sgmltut.html#h-3.2.4>.
The reference Dan Connolly used to support his assertion that comments
are
markup in
<URL:http://lists.w3.org/Archives/Public/www-html/1999Nov/0024.html>,
<URL:http://www.w3.org/MarkUp/SGML/productions.html#prod91>, is
effectively
unreadable (and unreachable) for the bulk of the target audience for the 
HTML 4.01 spec.

3. Make whatever statement exists that the DTD is not the entire
definition
of the HTML spec more visible to those who may not heed it by repeating
it
at the beginning of <URL:http://www.w3.org/TR/html40/sgml/dtd.html>, and
also
possibly by stating it very plainly in the introductory material if it
is
not so already.

Change 1 would make the reality plain to those who are not going to 
read the whole spec. Change 2 would formally state what not everyone
sees
as obvious - that comments are markup. Change 3 would caution readers
against an over-reliance on the DTD as a primary tool for understanding
HTML.

I hope that these comments may be of some use.

~ Sean Richardson   sidr@albedo.net

Received on Tuesday, 16 November 1999 23:37:34 UTC