Temporal Contextual Logic Programming

The importance of temporal representation and reasoning is well known not only in the database community but also in the artificial intelligence one. Contextual Logic Programming [António Porto and Luís Monteiro. Contextual logic programming. In Giorgio Levi and Maurizio Martelli, editors, Proceedings 6th Intl. Conference on Logic Programming, Lisbon, Portugal, 19–23 June 1989, pages 284–299. The MIT Press, Cambridge, MA, 1989] (CxLP) is a simple and powerful language that extends logic programming with mechanisms for modularity. Recent work not only presented a revised specification of CxLP together with a new implementation for it but also explained how this language could be seen as a shift into the Object-Oriented Programming paradigm [Salvador Abreu and Daniel Diaz. Objective: In minimum context. In Catuscia Palamidessi, editor, ICLP, volume 2916 of Lecture Notes in Computer Science, pages 128–147. Springer, 2003]. In this paper we propose a temporal extension of such language called Temporal Contextual Logic Programming. Such extension follows a reified approach to the temporal qualification, that besides the acknowledge increased expressiveness of reification allows us to capture the notion of time of the context. Together with the syntax of this language we also present its operational semantics and an application to the management of workflows.