Priority rewriting: Semantics, confluence, and conditionals

  • Chilukuri K. Mohan
Regular Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 355)


Priority rewrite systems (PRS) are partially ordered finite sets of rewrite rules; in this paper, two possible alternative definitions for rewriting with PRS are examined. A logical semantics for priority rewriting is described, using equational formulas obtained from the rules, and inequations which must be assumed to permit rewriting with rules of lower priority. Towards the goal of using PRS to define data type and function specifications, restrictions are given that ensure confluence and encourage modularity. Finally, the relation between priority and conditional rewriting is studied, and a natural combination of these mechanisms is proposed.


Priority Rule Ground Term Equational Formula Logical Semantic Term Rewrite System 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Chilukuri K. Mohan
    • 1
  1. 1.School of Computer and Information ScienceSyracuse UniversitySyracuse

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