A TECHNIQUE FOR TRANSFORMING LOGIC PROGRAMS BY FOLD-UNFOLD TRANSFORMATIONS

This paper deals with the logic program transformation using the fold-unfold technique. The major problem in the strategies using fold-unfold transformation is to find a sequence of unfolding that permits the folding. In this paper we propose a technique that solves this problem for a particular class of logic programs. This technique consists in studying the possibility of folding for some simple or basic programs and then to apply these results for some more general logic programs. This technique permits to compute the sequence of unfolding to achieve a folding or to detect the impossibility of a folding, in the latter case the technique permits the invention of new predicates.