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Re: Couldn't XML allow and ignore omitted tag minimization



Sorry if this has been answered already -- I don't see it in my
mailbox, but am behind... :-(

Jon wrote about allowing - -,
> I am made uneasy by the thought that a legal DTD would then be stating
> specifically something that would not be true in XML, namely that
> certain omissions were allowed when, in fact, they would not be.  But
> I'm willing at least to entertain the argument that this tradeoff
> makes DTD maintenance a lot easier.

I think this is a red herring, an argument based on a false assumption.

Those people using SGML today will need conversion software for both DTD
and instance.  This might be something as simple as a perl script, or
it might use OCLC's FRED, for example.

Some people will use SGML internally, and translate to XML on the fly.

New valid XML files wil be valid SGML files, when you use the right
SGML declaration.

In no case was a promise made that all existing XML files or DTDs
could be used with XML, and we already know that most can't.

So adding - - back makes life no easier.  People can leave them out of
SGML DTDs today and turn OMITTAG off and generate cleaner data anyway.

Next we'll be asked to
* accept "&" in model groups
* accept mixed content with , and #PCDATA
* accept inclusions and exclusions
* add LINK (there's already been a proposal to add LINK to XML)
* add CONCUR, OMITTAG, DATATAG...
* add open-tag-entitie
* ignore the keyword "SDATA"

and so on, until an XML processor will have to include a full
SGML parser simply for the benefit of less than 1,000 people on
this list, and 10,000 people not on this list won't use XML.

So no, there's no need for anything to do with OMITTAG in XML.
And we need not to have things that are there for "SGML legacy
conversion".  Those who need to work with both systems will find
"O O" among the least of their challenges.

Lee


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