The Text Encoding Initiative schemas are maintained using a module
of the TEI called "tagdocs", which allows for describing elements,
attributes,
classes of elements, 'entities', and so on. The whole of the large TEI
Guidelines
are written in the same single document; hence the name of "ODD" for
this system - One Document Does it all.

The ODD format reverts to Relax NG markup for specifing the content
model of elements. From this we derive, as needed,

- documentaton (HTML, PDF, LaTeX, TEI XML etc)
- Relax NG schemas (RNC using trang)
- XSD schemas (using trang)
- DTDs (direct translation)

There is a complex and powerful system for writing customizations
(additions, deletions, changes, internationalization), expressed
in the same language.

Some pointers on http://www.tei-c.org/P5/; or I can describe
in detail as desired.


--
Sebastian Rahtz
Information Manager, Oxford University Computing Services
13 Banbury Road, Oxford OX2 6NN. Phone +44 1865 283431

OSS Watch: JISC Open Source Advisory Service
http://www.oss-watch.ac.uk