XML complexity, namespaces (was WG)

[Paul Prescod]

Chris Lilley wrote:
> 
> You know what they used to say about SGML; its assymetric. Getting the
> data in just takes a text editor, but getting it out again requires a
> consultant. Well, with XML, the effort to get some benefit from XML is
> reduced because of economy of scale - someone somewhere will have the
> dtd you want to do part of your job. Build what you want from a kit of
> parts that other people wrote; add a little glue, and off you go.

It doesn't work that way.

A DTD is a reflection of an organization's business model. It varies from
organization to organization. You can't directly use some else's UML model
nor their DTD directly. It certainly does help to be able to use someone
else's as a starting point. It is also useful to use industry standard
DTDs for interchange (after some form of mapping or translation).

DTDs can and should be shared, but you should expect to make
customizations for every organization. That in turn requires customization
to all of the software that works with the DTD. Customizations is easier
than starting from scratch but the problem is that it may touch every part
of the system: 

 * document types
 * document type documentation
 * editor customizations
 * metadata query GUIs
 * data entry GUIs
 * navigation GUIs
 * output specifications (all of them!)

That isn't glue anymore. It's a major project (though less major than
starting from scratch). And unfortunately it involves specialized
knowledge which will usually mean consulting. Most technical publications
departments have a very thin technical staff and they aren't going to
become experts in all of these areas.

In other words, XML is as asymmetric as SGML. Actually neither is really
very asymmetric because you can't (well, shouldn't) get data into them
before you have designed your document type. So input and output are both
pretty difficult if you compare them, say, to Microsoft Word which is
usually the benchmark people use to demonstrate how hard SGML systems are
to build.

-- 
 Paul Prescod  - ISOGEN Consulting Engineer speaking for only himself
 http://itrc.uwaterloo.ca/~papresco

"Perpetually obsolescing and thus losing all data and programs every 10
years (the current pattern) is no way to run an information economy or
a civilization." - Stewart Brand, founder of the Whole Earth Catalog
http://www.wired.com/news/news/culture/story/10124.html

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at ic.ac.uk
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on CD-ROM/ISBN 981-02-3594-1
To (un)subscribe, mailto:majordomo at ic.ac.uk the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at ic.ac.uk the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at ic.ac.uk)