A Situation Calculus Semantics for the Prolog Cut Operator 1
نویسنده
چکیده
Given a deenite logic program with cut, we proceed in two steps to give it a semantics. First, we delete cut from the program, and construct the basic action theory for the resulting cut-free program in the situation calculus according to (Lin and Reiter 3]). We then formalize the eeects of cut by adding to the basic action theory a situation calculus sentence that characterizes the set of situations (derivations) that are not eliminated by cut. We show that our semantics is well-behaved when the logic program is properly stratiied. We also show that according to this semantics, the usual implementation of the negation-as-failure operator using cut is prov-ably correct. Abstract. Given a deenite logic program with cut, we proceed in two steps to give it a semantics. First, we delete cut from the program, and construct the basic action theory for the resulting cut-free program in the situation calculus according to (Lin and Reiter 3]). We then formalize the eeects of cut by adding to the basic action theory a situation calculus sentence that characterizes the set of situations (derivations) that are not eliminated by cut. We show that our semantics is well-behaved when the logic program is properly stratiied. We also show that according to this semantics, the usual implementation of the negation-as-failure operator using cut is prov-ably correct.
منابع مشابه
Applications of the Situation Calculus To Formalizing Control and Strategy Information: The Prolog Cut Operator
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