Veri cation of Logic Programs with Delay Declarations

Logic programs augmented with delay declarations form a higly expressive programming language in which dynamic networks of processes that communicate asynchronously by means of multiparty channels can be easily created. In this paper we study correctness these programs. In particular, we propose proof methods allowing us to deal with occur check freedom, absence of deadlock, absence of errors in presence of arithmetic relations, and termination. These methods turn out to be simple modiications of the corresponding methods dealing with Prolog programs. This allows us to derive correct delay declarations by analyzing Prolog programs. Finally, we point out diiculties concerning proofs of termination.