Re: [docbook-tc] XML Policy?

[Michael Smith <smith@xml-doc.org>]

Norman Walsh <ndw@nwalsh.com> writes:

> At one time, we decided to abandon SGML. Later, in Philadelphia I
> think, we reversed that decision and decided we'd keep SGML support as
> a customization layer on the XML DTD. In the last few weeks, I've been
> asked about a number of practical issues that really make me uneasy.
> 
> Consider:
> 
> - xml:lang
> - xml:space
> - XML Base
> - XML Include
> 
> Supporting these in XML DTDs is hard, and it's going to start to look
> ugly in SGML. And we really need to consider moving to another schema
> language, I think.
> 
> Comments?

Given the problems, I'd be inclined to vote for re-reversing the
decision and dropping SGML support in 5.0 as was originally announced,
if that's still possible.

As far as moving to another schema language, now that the RELAX NG
official committee spec has been released, I'd be happy if we were to
start discussing the idea of a RELAX NG normative schema for DocBook.

To jump up on the soapbox for a minute, I think as users start to get
familiar with RELAX NG, they'll understand James Clark's description
of it as an "evolutionary refinement of well-proven ideas from SGML
and XML DTDs". I really believe most people will find it relatively
easy to learn, especially if they start out by looking at and using
James' non-XML syntax[1], which is very much like DTD syntax, but even
clearer and easier to read and write.

Getting back to the SGML issue, I guess we could poll the list and ask
what SGML-specific features people are actually using and relying on.
If a lot of the responses are just about markup minimization, then I'd
say it really doesn't seem worth the time and trouble to maintain
support just because of that. The only other DTD-specific thing I can
think of is exclusions. Most other SGML features-- like marked
sections in doc instances -- have nothing to do with the DTD, right?


[1] http://thaiopensource.com/relaxng/nonxml/