The undecidability of typability in the Lambda-Pi-calculus

  • Gilles Dowek
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 664)


The set of pure terms which are typable in the λII-calculus in a given context is not recursive. So there is no general type inference algorithm for the programming language Elf and, in some cases, some type information has to be mentioned by the programmer.


Normal Form Letter Alphabet Post Problem Unification Problem Order Match 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Gilles Dowek
    • 1
  1. 1.School of Computer ScienceCarnegie Mellon UniversityPittsburghUSA

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