Limits of ML-definability

  • Stefan Kahrs
Typing and Structuring Systems
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1140)


It is well-known that the type system of ML is overly restrictive in its handling of recursion: certain intuitively sound terms do not pass ML's type-check. We formalise this intuition and show that the restriction is semantical: there are computable (semantical) functions which cannot be expressed by well-typed (syntactical) terms.


definability polymorphism recursion ML completeness 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Stefan Kahrs
    • 1
  1. 1.Laboratory for Foundations of Computer ScienceUniversity of EdinburghEdinburghUK

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