Existence and Uniqueness of Normal Forms in Pure Type Systems with βη-conversion

  • Gilles Barthe
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1584)


Pure Type Systems ( PTS β s) provide a parametric framework for typed λ-calculi à la Church [1,2,10,11]. One important aspect of PTS β s is to feature a definitional equality based on β-conversion. In some instances however, one desires a stronger definitional equality based on βη-conversion. The need for such a strengthened definitional equality arises for example when using type theory as a logical framework or in categorical type theory.


Normal Form Type Theory Abstract Syntax Legal Term Induction Principle 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Gilles Barthe
    • 1
    • 2
  1. 1.Institutionen för DatavetenskapChalmers Tekniska HögskolaGöteborgSweden
  2. 2.Departamento de InformáticaUniversidade do MinhoBragaPortugal

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