On the power of simple diagrams

  • Roberto Di Cosmo
Regular Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1103)


In this paper we focus on a set of abstract lemmas that are easy to apply and turn out to be quite valuable in order to establish confluence and/or normalization modularly, especially when adding rewriting rules for extensional equalities to various calculi. We show the usefulness of the lemmas by applying them to various systems, ranging from simply typed lambda calculus to higher order lambda calculi, for which we can establish systematically confluence and/or normalization (or decidability of equality) in a simple way. Many result are new, but we also discuss systems for which our technique allows to provide a much simpler proof than what can be found in the literature.


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Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • Roberto Di Cosmo
    • 1
  1. 1.Ecole Normale SupérieureDMI-LIENS (CNRS URA 1327)ParisFrance

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