Partiality, State and Dependent Types

  • Kasper Svendsen
  • Lars Birkedal
  • Aleksandar Nanevski
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6690)


Partial type theories allow reasoning about recursively- defined computations using fixed-point induction. However, fixed-point induction is only sound for admissible types and not all types are admissible in sufficiently expressive dependent type theories.

Previous solutions have either introduced explicit admissibility conditions on the use of fixed points, or limited the underlying type theory. In this paper we propose a third approach, which supports Hoare-style partial correctness reasoning, without admissibility conditions, but at a tradeoff that one cannot reason equationally about effectful computations. The resulting system is still quite expressive and useful in practice, which we confirm by an implementation as an extension of Coq.


Type Theory Partial Type Dependent Type Inductive Type Separation Logic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Kasper Svendsen
    • 1
  • Lars Birkedal
    • 1
  • Aleksandar Nanevski
    • 2
  1. 1.IT University of CopenhagenDenmark
  2. 2.IMDEA SoftwareSpain

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