WANDA - a Higher Order Termination Tool (System Description)

Author Cynthia Kop

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Cynthia Kop
  • Radboud University, The Netherlands


Thanks go to Carsten Fuhs both for proof-reading and for creating a customised version of AProVE which gives an explicit example term for non-termination; to Julian Nagele for using CSIasciicircum ho to translate the pattern HRSs in COPS to AFSMs; and to the anonymous reviewers of FSCD 2020 whose thorough feedback helped to improve the paper.

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Cynthia Kop. WANDA - a Higher Order Termination Tool (System Description). In 5th International Conference on Formal Structures for Computation and Deduction (FSCD 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 167, pp. 36:1-36:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


Wanda is a fully automatic termination analysis tool for higher-order term rewriting. In this paper, we will discuss the methodology used in Wanda. Most pertinently, this includes a higher-order dependency pair framework and a variation of the higher-order recursive path ordering, as well as some non-termination analysis techniques and delegation to a first-order tool. Additionally, we will discuss Wanda’s internal rewriting formalism, and how to use Wanda in practice for systems in two different formalisms. We also present experimental results that consider both formalisms.

Subject Classification

ACM Subject Classification
  • Theory of computation → Equational logic and rewriting
  • higher-order term rewriting
  • termination
  • automatic analysis
  • dependency pair framework
  • higher-order recursive path ordering


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