Compatibility of XML language versions

Abstract

Individual organisations as well as industry consortia are currently defining application and domain-specific languages using the extended Markup Language (XML) standard of the World Wide Web Consortium (W3C). The paper shows that XML languages differ in significant aspects from generic software engineering artifacts and that they therefore require a specific approach to version and configuration management. When an XML language evolves, consistency between the language and its instance documents needs to be preserved in addition to the internal consistency of the language itself. We propose a definition for compatibility between versions of XML languages that takes this additional need into account. Compatibility between XML languages in general is undecidable. We argue that the problem can become tractable using heuristic methods if the two languages are related in a version history. We propose to evaluate the method by using different versions of the Financial products Markup Language (FpML), in the definition of which we participate. © Springer-Verlag Berlin Heidelberg 2003.