Solving a unification problem under constrained substitutions using tree automata

  • Yuichi Kaji
  • Toru Kasami
  • Tom Fujiwara
Part of the Lecture Notes in Computer Science book series (LNCS, volume 880)


A generalization of a unification problem for term rewriting systems, named a unification problem under constrained substitutions is investigated, and a procedure to solve the problem with the help of tree automata is presented. Since the problem is undecidable in general, there are rewriting systems for which our procedure does not terminate. We clarify a sufficient condition undet which the procedure always terminates, and review some classes of rewriting systems that satisfy the condition. These classes include a known decidable class introduced in [6].


term rewriting systems unification problems constrained substitutions tree automata 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Yuichi Kaji
    • 1
  • Toru Kasami
    • 1
  • Tom Fujiwara
    • 2
  1. 1.Graduate School of Information ScienceNara Institute of Science and TechnologyNaraJapan
  2. 2.Department of Information and Computer SciencesOsaka UniversityOsakaJapan

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