Fairness in term rewriting systems

  • Sara Porat
  • Nissim Francez
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 202)


The notion of fair derivation in a term-rewriting system is introduced, whereby every rewrite rule enabled infinitely often along a derivation is infinitely-often applied. A term-rewriting system is fairly-terminating iff all its fair derivations are finite. The paper presents the following question: is it decidable, for an arbitrary ground term rewriting system, whether it fairly terminates or not? A positive answer is given for several subcases. The general case remains open.


Function Symbol Fair Termination Ground Term Rewrite Rule Global Finiteness 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • Sara Porat
    • 1
  • Nissim Francez
    • 1
  1. 1.Computer Science Dept. TechnionHaifaIsrael

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