SAS 1997: Static Analysis pp 265-277 | Cite as

Satisfying subtype inequalities in polynomial space

  • Alexandre Frey
Functional Programming II
First Online:
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1302)

Abstract

This paper studies the complexity of type inference in λ-calculus with subtyping. Type inference is equivalent to solving systems of subtype inequalities. We consider simple types ordered structurally from an arbitrary set of base subtype assumptions. In this case, we give a PSPACE upper bound. Together with the known lower bound, this result settles completely the complexity of type inference over simple types, which is PSPACE-complete. We use a technique of independent theoretical interest that simplifies existing methods developed in the literature. Finally the algorithm, although mainly theoretical, can lead to a slight practical improvement of existing implementations.

Keywords

Finite Type Simple Type Type Inference Polynomial Space Conference Record 
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 1997

Authors and Affiliations

  • Alexandre Frey
    • 1
  1. 1.Centre de Mathématiques Appliquées, École des Mines de ParisParis

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