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Re: OMITTAG specifications in element declarations



At 02:50 PM 11/2/96 EST, lee@sq.com wrote:
>Eve asked about the "- -" ommitted tag minimization parameter, and
>adding it in to XML.
>
>It is a red herring to say that putting them in XML would help
>compatibility: if you have OMITTAG YES in your DTD, you need to
>run SPAM or otherwise ensure that there are no omitted tags.
>XML applictions won't handle your text otherwise, so it doesn't
>matter if they wil handle the DTD or not.
>
>It would be like adding SHORTREF parsing to XML so that you can parse
>DTDs with SHORTREF -- if you're using SHORTREF, changing the DTD is
>the least of the work you have to do, and is a necessary step in
>any case.
>
>So no strange and spurious tokens in XML.  They are not needed for
>SGML conformance, they do not add to the expressive power of the
>language, they add slightly to language complexity, and not having them
>will actually _help_ interoperability with SGML.
>
>Lee

I realize it's a bit strange to allow no-op characters, but new XML DTDs 
simply won't use them.  The problem is not so much explaining these tokens 
to new XML users; it's making existing DTDs usable in XML.  I'm not
saying new XML DTDs should *require* this field, just allow it.

The difference between OMITTAG and SHORTREF is that pretty much *every*
DTD today includes the OMITTAG field, even if just "- -", partly because 
the SGML declaration (where OMITTAG is set to YES or NO) is a component of 
SGML documents as a whole, and DTDs technically don't automatically
"come with" their own SGML declaration.

For me, this definitely comes under the heading of deciding whether or
not to punish existing SGML users.

        Eve