Proof Pearl: Looping Around the Orbit

  • Steven Obua
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4732)


We reexamine the While combinator of higher-order logic (HOL) and introduce the For combinator. We argue that both combinators should be part of the toolbox of any HOL practitioner, not only because they make efficient computations within HOL possible, but also because they facilitate elegant inductive reasoning about loops. We present two examples that support this argument.


Planar Graph Induction Rule Loop Index Oriented Edge Loop State 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Steven Obua
    • 1
  1. 1.Technische Universität München, D-85748 Garching, Boltzmannstr. 3Germany

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