Properties of Input-Consuming Derivations

TL;DR

This paper investigates the properties of input-consuming derivations in moded logic programs, demonstrating a weak switching lemma and providing algebraic conditions for termination, relevant for dynamic scheduling and delay constructs.

Contribution

It introduces a weak switching lemma for input-consuming derivations in nicely-moded programs and offers algebraic criteria for their termination, advancing understanding of dynamic scheduling.

Findings

Weak switching lemma holds for nicely-moded programs

Algebraic characterization of termination exists under certain conditions

Input-consuming derivations can model dynamic scheduling behaviors

Abstract

We study the properties of input-consuming derivations of moded logic programs. Input-consuming derivations can be used to model the behavior of logic programs using dynamic scheduling and employing constructs such as delay declarations. We consider the class of nicely-moded programs and queries. We show that for these programs a weak version of the well-known switching lemma holds also for input-consuming derivations. Furthermore, we show that, under suitable conditions, there exists an algebraic characterization of termination of input-consuming derivations.