For many years the Text Encoding Initiative (TEI) has used a specialised high-level XML vocabulary known as ODD in the "literate programming" paradigm to define its influential Guidelines, from which schemas or DTDs in other schema languages are derived. This paper describes a minor but significant modification to the TEI ODD language and explores some of its implications. In the current ODD language, the detailed content model of an element is expressed in RELAX NG, embedded inside TEI markup. We define a set of additional elements which permit the ODD language to cut its ties with existing schema languages, making it an integrated and independent whole rather than an uneasy hybrid restricted in its features to the intersection of the three current schema languages. This may pave the way for future developments in the management of structured text beyond the XML paradigm. We describe the additional features, and discuss the problems of both implementing them, and of migrating existing TEI definitions.
Lou Burnard and Sebastian Rahtz. "A complete schema definition language for the Text Encoding Initiative"
Presented at XML London 2013, June 15-16th, 2013.