A new declarative semantics for logic languages. In R. Optimizations of bottom-up evaluation with non-ground terms. In Miller 15], pages 557{574. 19 orthogonal to the type of program to which memoing is applied. With some care, they can be used in the context of full Prolog, speciied as we have suggested by a programmer controlled directive. The practicality of the special case of ground, multi...