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 
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 1984

Authors and Affiliations

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

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