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Intensionality versus extensionality and Primitive Recursion

  • Pierre Valarcher
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1179)

Abstract

The set of primitive recursive functions (pr) accepts many definitions. We study three languages (presented as rewriting rules) that compute pr functions and show that they do not have the same intensional behaviour (a new function associate to algorithm) from an input/output point of view (i.e. they do not compute in the same way): classical Primitive Recursion (PR), Primitive Recursion with Variable parameters (PRV) and Primitive Recursion on Lists of integers (PRL). We use denotational semantics to formally study the behaviour of algorithms. We give a complete characterization of the intensional behaviour of the language PR. We show that all unary increasing pr functions and a large class of stable pr functions may be an intensional behaviour of PRV and PRL.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Pierre Valarcher
    • 1
  1. 1.Faculté des Sciences et de TechniquesLaboratoire d'Informatique de RouenMont-Saint-Aignan Cedex

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