This paper introduces the Schematron language and the available implementations.An overview of the architecture, with a view to producing customised versions is also provided.
The Schematron conformance language for custom implementation is also introduced.
The paper completes with some suggestions of possible future extensions.
Schematron is a useful and accessible supplement to other schema languages.
The open-source XSLT implementation is based around a core framework which is open for extension and customisation.
Yet the fundamental approach adopted by these languages does not diverge greatly from the DTD paradigm: the definition of schemas using regular grammars.
Less formally, schemas are constructed by defining parent-child and sibling relationships [Jelliffe1999a]. However this means that DTDs, and similar derivatives, are unable to define (and hence constrain) the other kinds of relationships that exist amongst markup elements within a document.
This paper provides an introduction to Schematron; an innovative XML validation language developed by Rick Jelliffe.
This innovation stems from selecting an alternative approach to validation than existing schema languages: Schematron uses a tree pattern based paradigm, rather than the regular grammars used in DTDs and XML schemas.
A trivial XML vocabulary is introduced for the purposes of generating examples.
The later sections in this paper provides an overview of the open source XSLT framework used to implement the Schematron language.
As the XPath specification [XPath] shows, there are many possible kinds of relationship, known as 'axes'.