Termination of Constraint Contextual Rewriting
نویسندگان
چکیده
Abstra t. The e e tive integration of de ision pro edures in formula simpli ation is a fundamental problem in me hani al veri ation. The main sour e of diÆ ulty o urs when the de ision pro edure is asked to solve goals ontaining symbols whi h are interpreted for the prover but uninterpreted for the de ision pro edure. To ope with the problem, Boyer & Moore proposed a te hnique, alled augmentation, whi h extends the information available to the de ision pro edure with suitably sele ted fa ts. Constraint Contextual Rewriting (CCR, for short) is an extended form of ontextual rewriting whi h generalizes the Boyer & Moore integration s hema. In this paper we give a detailed a ount of the ontrol issues related to the termination of CCR. These are parti ularly subtle and ompli ated sin e augmentation is mutually dependent from rewriting and it must be prevented from inde nitely extending the set of fa ts available to the de ision pro edure. A proof of termination of CCR is given.
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