A simple abstract model of Eiffel is introduced, and its denotational seman-tics is defined using VDM style. A static analysis approach is presented to treatmultiple inheritance and renaming mechanism. Within the fram...A simple abstract model of Eiffel is introduced, and its denotational seman-tics is defined using VDM style. A static analysis approach is presented to treatmultiple inheritance and renaming mechanism. Within the framework of deno-tational semantics iatroduced in this paper, the key features of Eiffel, such asidentification, classification, multiple inheritance, polymorphism and dynamicbinding, can be adequately characterized.展开更多
Several extensions of the logic programming language Prolog to non Horn clauses use case analysis to handle non-Horn clauses. In this paper, analytical and empirical evidences are presented to show that, by making a ...Several extensions of the logic programming language Prolog to non Horn clauses use case analysis to handle non-Horn clauses. In this paper, analytical and empirical evidences are presented to show that, by making a set of clauses less 'non-Horn' using predicate renaming, the performance of these case-analysis based procedures can be improved significantly. In addition, the paper also investigated the problem of efficiently constructing a predicate renaming that reduces the degree of 'non-Hornness' of a clause set maximally. It is shown that this problem of finding a predicate renaming to achieve minimal 'non-Hornness' is NP-complete.展开更多
文摘A simple abstract model of Eiffel is introduced, and its denotational seman-tics is defined using VDM style. A static analysis approach is presented to treatmultiple inheritance and renaming mechanism. Within the framework of deno-tational semantics iatroduced in this paper, the key features of Eiffel, such asidentification, classification, multiple inheritance, polymorphism and dynamicbinding, can be adequately characterized.
文摘Several extensions of the logic programming language Prolog to non Horn clauses use case analysis to handle non-Horn clauses. In this paper, analytical and empirical evidences are presented to show that, by making a set of clauses less 'non-Horn' using predicate renaming, the performance of these case-analysis based procedures can be improved significantly. In addition, the paper also investigated the problem of efficiently constructing a predicate renaming that reduces the degree of 'non-Hornness' of a clause set maximally. It is shown that this problem of finding a predicate renaming to achieve minimal 'non-Hornness' is NP-complete.
