Oriented equational clauses as a programming language

  • L. Fribourg
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 172)


In the Prolog language, Horn clauses of first-order logic are regarded as programs, and the resolution procedure is used as an interpreter.

In this paper, we present the formalism of Horn oriented equational clauses (Horn clauses with a rewrite rule as the head part, and a list of equations as the body part). We show that such a formalism can be interpreted as a logic language with built-in equality, and that a procedure, based on clausal superposition, can be used as an interpreter.

We define, the operational, model-theoretic and fixpoint semantics of the language, and prove their equivalence.

Then we point out the advantages of such a programming language:
  • embodying Prolog,

  • mixing functional and relational features,

  • handling the equality relation

Lastly, we present experiments performed with an implemented interpreter.


Predicate Logic Horn Clause Equational Logic Prolog Program Empty Clause 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • L. Fribourg
    • 1
  1. 1.Laboratoires de Marcoussis - C.G.E.MarcoussisFrance

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