Extensions of pure type systems

  • Gilles Barthe
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 902)


We extend pure type systems with quotient types and subset types and establish an equivalence between four strong normalisation problems: subset types, quotient types, definitions and the so-called K-rules. As a corollary, we get strong normalisation of ECC with definitions, subset and quotient types.


Type Theory Reduction Rule Elimination Rule Type Constructor Strong Normalisation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Gilles Barthe
    • 1
  1. 1.Faculty of Mathematics and InformaticsUniversity of NijmegenThe Netherlands

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