To appear in Theory and Practice of Logic Programming (TPLP). Tabling is a
commonly used technique in logic programming for avoiding cyclic behavior of
logic programs and enabling more declarative program definitions. Furthermore,
tabling often improves computational performance. Rational term are terms with
one or more infinite sub-terms but with a finite representation. Rational terms
can be generated in Prolog by omitting the occurs check when unifying two
terms. Applications of rational terms include definite clause grammars,
constraint handling systems, and coinduction. In this paper, we report our
extension of YAP's Prolog tabling mechanism to support rational terms. We
describe the internal representation of rational terms within the table space
and prove its correctness. We then use this extension to implement a tabling
based approach to coinduction. We compare our approach with current coinductive
transformations and describe the implementation. In addition, we present an
algorithm that ensures a canonical representation for rational terms.Comment: To appear in Theory and Practice of Logic Programming (TPLP