Combinatorial problems, combinator equations and normal forms

  • Corrado Böhm
  • Mariangiola Dezani-Ciancaglini
Tuesday Morning
Part of the Lecture Notes in Computer Science book series (LNCS, volume 14)


Some cases of solvability of the convertibility equation MX=N, where M,N and X are normal forms of the λ-K-β-calculus are considered and their relationship to pattern-matching problems is discussed. In particular, the solvability of such an equation is decided in the cases:
  1. i)

    N ≡ I and M = BF

  2. ii)

    N ≡ I and M = CBF where F is a normal form

  3. iii)

    N is an arbitrary normal form.


For this purpose, a polynomial representation and subsequently a tree representation of normal forms are introduced.


Normal Form Free Variable Terminal Node Tree Representation Current Path 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1974

Authors and Affiliations

  • Corrado Böhm
    • 1
  • Mariangiola Dezani-Ciancaglini
    • 1
  1. 1.Istituto di Scienza dell'Informazione dell'Università di TorinoTorino

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