Re: Couldn't XML allow and ignore omitted tag minimization
Tim Bray <email@example.com> wrote:
> I must be missing something. If the DTD is to work with XML, it
> *must* have "- - " before all content models of non-empty elements,
> and "- O " before empty elements, if you were to put in OMITTAG YES.
No: The DTD can use whatever tag omissibility declarations
it wants, as long as the _instance_ doesn't omit any tags.
> So you might as well put in OMITTAG NO. So you might as well lose
> the -'s and O's.
> Can you outline a scenario where you'd want to have OMITTAG YES and
> still be working with XML? - Tim
You might want to create documents in "full SGML",
then run them through a normalizer before publishing
them as XML. Converting an SGML document instance to
XML-compatible syntax is fairly straightforward, but
rewriting an SGML DTD to be XML-compliant is quite
complicated; there are many, many subtle differences
This might not be an issue though: there are so many other
restrictions in XML that writing a DTD that is simultaneously
legal XML and useful SGML might not be possible even
if XML did allow "[-o] [-o]" in ELEMENT declarations.