Termination of Simply Moded Logic Programs with Dynamic Scheduling

Abstract

In logic programming, dynamic scheduling indicates the feature by means of which the choice of the atom to be selected at each resolution step is done at runtime and does not follow a fixed selection rule such as the left-to-right one of Prolog. Input consuming derivations were introduced to model dynamic sched­uling while abstracting from the technical details. In this article, we provide a sufficient and necessary criterion for termination of input consuming derivations of simply moded logic programs. The termination criterion we propose is based on a denotational semantics for partial derivations which is defined in the spirit of model-theoretic semantics previously proposed for left-to-right derivations.