Lisp-based RDF Processor

Abstract

Semantic Web is a promising application area for Lisp programming language as well as Prolog, because basic requirements for semantic web processing such as axiom, entailment, and constraint are also basic vocabularies and infrastructure of inference in AI. Roughly speaking, from the viewpoint of the implementation, semantic web processors fall into a few categories; statement-based (XML-based), graph-based (triple-based), and frame-based or object-based. Despite that there are diverse implements on semantic web processors and toolkits in various programming languages; there is only one implement in Lisp, that is subject-predicate-object triple based. We have developed an object-based RDFS processor on CLOS using the Meta-Object Protocol, with straightforward mapping of RDFS class to CLOS class and RDFS individual to CLOS instance. By this mapping, we have obtained an efficient performance of processing instead of the difficulty of implementation. This paper describes an implementation of the processor on CLOS, and discusses ideas to extend it to OWL. We claim that the ends of Semantic Web processing will be attained through this approach, namely meta-object reflective approach, since CLOS is one of reflective languages and the processor is expected to provide meta-modeling facilities in OWL Full level.