Completion with history-dependent complexities for generated equations

  • Harald Ganzinger
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 332)


The paper presents a new system of inference rules for the completion of conditional equations. Conditional equations that are generated during completion can either be eliminated, oriented into reductive rewrite rules or considered as nonoperational. Rewrite rules are, as usual, subject to critical pair computation. Nonoperational equations are superposed by the rewrite rules on one of their conditions. A conditional equation can be eliminated if there is also a proof of the equation which is simpler than the equation itself. The purpose of this paper is to present a technique in which the origin of an equation defines the complexity bound which alternative proofs must respect. This technique is shown to be particularly useful in the conditional case, making the completion process terminate on a number of nontrivial specifications which it would fail to terminate otherwise.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • Harald Ganzinger
    • 1
  1. 1.Fachbereich InformatikUniversität DortmundDortmund 50W. Germany

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