International Conference on Rewriting Techniques and Applications

RTA 2014: Rewriting and Typed Lambda Calculi pp 46-60 | Cite as

Proving Confluence of Term Rewriting Systems via Persistency and Decreasing Diagrams

  • Takahito Aoto
  • Yoshihito Toyama
  • Kazumasa Uchida
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8560)


The decreasing diagrams technique (van Oostrom, 1994) has been successfully used to prove confluence of rewrite systems in various ways; using rule-labelling (van Oostrom, 2008), it can also be applied directly to prove confluence of some linear term rewriting systems (TRSs) automatically. Some efforts for extending the rule-labelling are known, but non-left-linear TRSs are left beyond the scope. Two methods for automatically proving confluence of non-(left-)linear TRSs with the rule-labelling are given. The key idea of our methods is to combine the decreasing diagrams technique with persistency of confluence (Aoto & Toyama, 1997).


Confluence Persistency Decreasing Diagrams Rule- Labelling Non-Linear Term Rewriting Systems 


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Takahito Aoto
    • 1
  • Yoshihito Toyama
    • 1
  • Kazumasa Uchida
    • 1
  1. 1.RIECTohoku UniversityAoba-ku, SendaiJapan

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