Selective Backtracking for Logic Programs
نویسندگان
چکیده
We present a selective backtracking method for Horn clause programs, as applied to Prolog (2)[8)(11)[12], a programming language based on first-order predicate calculus (3)(4)~ developed at the university of Marseille (18]. This method is based on the general method expounded in (7] for backtracking intelligently in AND/OR trees. It consists, essentially, in avoiding backtracking to any goal whose alternative solutions cannot possibly prevent the repetition of the failures which caused backtracking. This is a renewed version of an earlier report (8), which was spurred by the work of Bruynooghe (1). In (g] we present an implementation of a selective backtracking interpreter using the methods discussed in this paper.
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