Modular higher-order E-unification

  • Tobias Nipkow
  • Zhenyu Qian
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 488)


The combination of higher-order and first-order unification algorithms is studied. We present algorithms to compute a complete set of unifiers of two simply typed λ-terms w.r.t. the union of α, β and η conversion and a first-order equational theory E. The algorithms are extensions of Huet's work and assume that a complete unification algorithm for E is given. Our completeness proofs require E to be at least regular.


Normal Form Function Constant Logic Programming Free Variable Equational Theory 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • Tobias Nipkow
    • 1
  • Zhenyu Qian
    • 2
  1. 1.Computer LaboratoryUniversity of CambridgeCambridgeEngland
  2. 2.FB InformatikUniversität BremenBremen 33Germany

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