A Logic Programming Language with Lambda-Abstraction, Function Variables, and Simple Unification
نویسنده
چکیده
It has been argued elsewhere that a logic programming language with function variables and λ-abstractions within terms makes a good meta-programming language, especially when an object-language contains notions of bound variables and scope. The λProlog logic programming language and the related Elf and Isabelle systems provide meta-programs with both function .variables and λ-abstractions by containing implementations of higher-order unification. This paper presents a logic programming language, called Lλ, that also contains both function variables and λ-abstractions, although certain restrictions are placed on occurrences of function variables. As a result of these restrictions, an implementation of Lλ does not need to implement full higher order unification. Instead, an extension to first-order unification that respects bound variable names and scopes is all that is required. Such unification problems are shown to be decidable and to possess most general unifiers when unifiers exist. A unification algorithm and logic programming interpreter are described and proved correct. Several examples of using Lλ as a meta-programming language are presented. Comments University of Pennsylvania Department of Computer and Information Science Technical Report No. MSCIS-90-54. This technical report is available at ScholarlyCommons: http://repository.upenn.edu/cis_reports/576 A Logic Programming Language with Lambda Abstraction, Function Variables and Simple Unification MS-CIS-90-54 LINC LAB 182
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A Logic Programming Language with Lambda - Abstraction , Function Variables , and Simple Uni cationDale
It has been argued elsewhere that a logic programming language with function variables and-abstractions within terms makes a good meta-programming language, especially when an object-language contains notions of bound variables and scope. The Prolog logic programming language and the related Elf and Isabelle systems provide meta-programs with both function variables and-abstractions by containi...
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