Strategy-controlled reduction and narrowing

  • Peter Padawitz
Unification By Narrowing
Part of the Lecture Notes in Computer Science book series (LNCS, volume 256)


The inference rules "reduction" and "narrowing" are generalized from terms resp equations to arbitrary atomic formulas. Both rules are parameterized by strategies to control the selection of redices. Church-Rosser properties of the underlying Horn clause specification are shown to ensure both completeness and strategy independence of reduction. "Uniformity" turns out as the crucial property of those reduction strategies which serve as complete narrowing strategies. A characterization of uniformity (and hence completeness) of leftmost-outermost narrowing is presented.


Partial Function Predicate Symbol Horn Clause Operation Symbol Conditional Equation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • Peter Padawitz
    • 1
  1. 1.Fakultät für Mathematik und Informatik Universität PassauGermany

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