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Solving goals in equational languages

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Conditional Term Rewriting Systems (CTRS 1987)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 308))

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Abstract

Solving equations in equational Horn-clause theories is a programming paradigm that combines logic programming and functional programming in a clean manner. Languages like Eqlog, Slog and Rite, express programs as conditional rewrite rules and goals as equations to be solved. Procedures for completion of conditional equational theories, in a manner akin to that of Knuth and Bendix for unconditional theories, also require methods for solving equations appearing in conditions. Rewrite-based logic-programming uses (conditional) narrowing to solve equational goals. Recently a different, topdown equation solving procedure was proposed for unconditional rewrite systems. In this paper, we express equational goal solving using conditional rules. Some refinements are described: the notion of operator derivability is used to prune useless paths in the search tree and our use of oriented goals eliminates some redundant paths leading to non-normalized solutions. Our goal-directed method can also be extended to handle conditional systems.

This research was supported in part by the National Science Foundation under Grant DCR 85-13417.

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Authors and Affiliations

  1. Department of Computer Science, University of Illinois at Urbana-Champaign, 61801, Urbana, Illinois, U.S.A.

    Nachum Dershowitz & G. Sivakumar

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  1. Nachum Dershowitz
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  2. G. Sivakumar
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S. Kaplan J. -P. Jouannaud

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© 1988 Springer-Verlag Berlin Heidelberg

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Dershowitz, N., Sivakumar, G. (1988). Solving goals in equational languages. In: Kaplan, S., Jouannaud, J.P. (eds) Conditional Term Rewriting Systems. CTRS 1987. Lecture Notes in Computer Science, vol 308. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-19242-5_4

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  • DOI: https://doi.org/10.1007/3-540-19242-5_4

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-19242-8

  • Online ISBN: 978-3-540-39166-1

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