Inheritance hierarchy mechanism in prolog

  • Kiyoshi Akama
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 264)


PAL is an extended prolog to deal with inheritance hierarchy (IH). It adopts new patterns called class bound variables (CBVs). CBVs are different from variables with constraints in existing prolog systems, such as variables with "frozen" goals in prolog-II and term descriptions, in that class constraints of CBVs change in the inference when they are unified with other CBVs. The unification is efficiently executed by using the restriction on the IH structure, such as the exclusiveness among brother classes in IH. CBVs and the fast unification method improve the inferential efficiency greatly by suppressing combinatorial explosions, which might be caused by exhaustive searches in the inference in other systems.


Execution Time Exhaustive Search Term Description Class Constraint Combinatorial Explosion 
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 1987

Authors and Affiliations

  • Kiyoshi Akama
    • 1
  1. 1.Department of Behavioral Science, Faculty of LettersHokkaido UniversitySapporo-shiJapan

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