Type reconstruction in Fω is undecidable

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


We investigate the Girard's calculus Fω as a “Curry style” type assignment system for pure lambda terms. We prove that the type-reconstruction problem for Fω is undecidable (even with quantification restricted to constructor variables of rank 1). In addition, we show an example of a strongly normalizable pure lambda term that is untypable in Fω.


Turing Machine Type Inference Lambda Calculus Polymorphic Type Constructor Variable 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Paweł Urzyczyn
    • 1
  1. 1.Institute of InformaticsUniversity of WarsawWarszawaPoland

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