Proof pearl: defining functions over finite sets

  • Authors:
  • Tobias Nipkow;Lawrence C. Paulson

  • Affiliations:
  • Institut für Informatik, Technische Universität München, Germany;Computer Laboratory, University of Cambridge, England

  • Venue:
  • TPHOLs'05 Proceedings of the 18th international conference on Theorem Proving in Higher Order Logics
  • Year:
  • 2005

Quantified Score

Hi-index 0.00

Visualization

Abstract

Structural recursion over sets is meaningful only if the result is independent of the order in which the set's elements are enumerated. This paper outlines a theory of function definition for finite sets, based on the fold functionals often used with lists. The fold functional is introduced as a relation, which is then shown to denote a function under certain conditions. Applications include summation and maximum. The theory has been formalized using Isabelle/HOL .