Extensionality of Simply Typed Logic Programs
نویسنده
چکیده
We set up a framework for the study of extensionality in the context of higher-order logic programming. For simply typed logic programs we propose a novel declarative semantics, consisting of a model class with a semicomputable initial model, and a notion of extensionality. We show that the initial model of a simply typed logic program, in case the program is extensional, collapses into a simple, set-theoretic representation. Given the undecidability of extensionality in general, we develop a decidable, syntactic criterion which is sufficient for extensionality. Some typical examples of higher-order logic programs are shown to be extensional. 1991 Mathematics Subject Classification: 68N05, 68N17, 68Q6
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