Logic program semantics for programming with equations

  • Joxan Jaffar
  • Peter J. Stuckey
Session 3b: Theory And Semantics
Part of the Lecture Notes in Computer Science book series (LNCS, volume 225)


We consider logic programming-like systems which are based on solving equations in a given structure as opposed to obtaining unifiers. While such systems are elegant from an operational point of view, a logical interpretation of the programs is not always apparent. In this paper, we restrict ourselves to the class of structures ℜ satisfying the eliminable variable property: we can construct an explicit definition, in the form of one system of equations, of the set of solutions to any ℜ-solvable system of equations. Correspondingly, we consider only the class of equality theories E such that every E-unifiable system of equations has an E-mgu. We then state three properties which provide basic relationships between E and ℜ. We prove that their satisfaction establishes an equivalence between a program considered as an equation solving engine (with respect to a structure) and the program considered as a logic program (with respect to a corresponding equality theory). A logical basis for these programs is thus given.


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6. References

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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Joxan Jaffar
    • 1
  • Peter J. Stuckey
    • 1
  1. 1.Department of Computer ScienceMonash UniversityVictoriaAustralia

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