An Australian expert in [[XML (Extensible Markup Language)]] and a prominent figure in the development of web and data standards. He is best known as the creator of [[Schematron]], a rule-based validation language for XML.
Career and Contributions
Jelliffe has significantly influenced the XML community through his technical innovations, authorship, and active involvement in standards bodies.Schematron
His most notable contribution is the creation of Schematron, an XML schema language that uses [[XPath]] expressions to define constraints on the structure and content of XML documents. Unlike traditional XML schema languages like [[XML Schema Definition (XSD)]], which primarily focus on defining what is allowed, Schematron emphasizes asserting what is true or false about the document. This approach allows for more flexible, contextual, and human-readable validation rules, often used for enforcing business rules, ensuring data quality, and checking against complex patterns difficult to express in grammar-based schemas. Schematron has been standardized by [[ISO (International Organization for Standardization)]] as ISO/IEC 19757-3.Standards Development
Jelliffe has been actively involved in the development of numerous international standards, particularly within the [[World Wide Web Consortium (W3C)]] and ISO. His work includes contributions to:- [[XSLT (Extensible Stylesheet Language Transformations)]]
- [[XPath (XML Path Language)]]
- [[XML Schema (W3C XML Schema)]] (as a contributor to discussions and specifications)
- Various other XML-related specifications.
He is known for advocating for practical, implementable standards and for offering critical perspectives on the complexity of some specifications.
Authorship and Consulting
Jelliffe is the author of "The XML & SGML Cookbook," a widely referenced resource for developers working with XML and its predecessor, [[SGML (Standard Generalized Markup Language)]]. He also maintains a personal blog where he discusses topics related to XML, web standards, typography, and computing.Throughout his career, he has worked as a consultant, advising organizations on XML strategy, implementation, and best practices. He has held positions at various institutions, including the Academia Sinica Computing Centre in Taiwan, where he contributed to significant computing projects.
Philosophy and Influence
Jelliffe's work often emphasizes the importance of clear, human-readable rules and the practical application of technology. His creation of Schematron reflects a philosophy that validation should be extensible and adaptable to complex business logic, complementing rather than replacing grammar-based schemas. He has influenced many developers and architects to adopt more robust and flexible XML validation strategies.See Also
- [[Schematron]]
- [[XML]]
- [[XPath]]
- [[W3C]]
External Links
- (A real encyclopedia entry would include links to Rick Jelliffe's blog, professional profiles, and official Schematron resources.)