Modular Rule-Based Promgramming in 2APL

Abstract

Rule markup languages will be the vehicle for using rules on the Web and in other distributed systems. They allow publishing, deploying, executing and communicating rules in a network. They may also play the role of a lingua franca for exchanging rules between different systems and tools. In a narrow sense, a rule markup language is a concrete (XML-based) rule syntax for the Web. In a broader sense, it should have an abstract syntax as a common basis for defining various concrete languages addressing different consumers. The main purposes of a rule markup language are to permit the publication, interchange and reuse of rules. This chapter introduces important requirements and design issues for general Web rule languages to fulfill these tasks. Characteristics of several important general standardization or standards-proposing efforts for (XML-based) rule markup languages including W3C RIF, RuleML, R2ML, SWRL as well as (human-readable) Semantic Web rule languages such as TRIPLE, N3, Jena, and Prova are discussed with respect to these identified issues.