K I N F O R M a T I K Im Stadtwald W 6600 Saarbr Ucken Germany Authors' Addresses Publication Notes
نویسندگان
چکیده
We extend previous work on di erence identi cation and reduction as a technique for automated reasoning. We generalize uni cation so that terms are made equal not only by nding substitutions for variables but also by hiding term structure. This annotation of structural di erences serves to direct rippling, a kind of rewriting designed to remove structural di erences in a controlled way. On the technical side, we give a rule-based algorithm for di erence uni cation, and analyze its correctness, completeness, and complexity. On the practical side, we present a novel search strategy (called leftrst search) for applying these rules in an e cient way. Finally, we show how this algorithm can be used in new ways to direct rippling and how it can play an important role in theorem proving and other kinds of automated reasoning.
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