W. Chen. A theory of modules based on second-order logic. In Proc. 4th IEEE Internat. Symposium on Logic Programming, pages 24-33, San Francisco, 1987.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....in Proc. 1993 ACM Symposium on Principles of Programming Languages. This research was supported in part by CEC DGIII EC Israel collaborative activity, ISC IL 90 PARFORCE 1 the entire program. Semantic treatments of modules in logic programs have been given by a number of authors (e.g. see [5, 29]) typically based on nontrivial extensions to Horn clause logic that lead to complex semantics; it appears to us that the development of abstract interpretations based on such semantics is not entirely straightforward. The semantics we consider here as a basis for abstract interpretations is a ....

....with program modules. Gaifmann et al. propose to adopt clauses as semantic objects in order to characterize partial computations (from the head to the body) and to enable different notions of composition. Logical semantics for modules in logic programs have been proposed by a number of authors [5, 29]. These are typically based on various extensions to Horn logic: for example, Chen s treatment of modules [5] is based on secondorder logic, while Miller s [29] uses implication goals in clause bodies. In [12] Comini et al. define 11 a taxonomy of semantics that can be derived by abstracting SLD ....

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W. Chen. A Theory of Modules Based on Second-Order Logic. In Proc. Fourth IEEE Int'l Symp. on Logic Programming, pages 24--33. IEEE Comp. Soc. Press, 1987.

....in [2] and [3] In [22] an elaborated ML style module system for Prolog is presented. As opposed to our language, in [22] the configuration of modules is strictly separated from the logic language itself. Another approach uses higher order features to incorporate modules into a logic language ([4], 5] The main contributions of this paper can be characterized as follows. We propose a first order deductive database language allowing to mix embedded implications and negation as failure. It has a simple iterated fixpoint semantics and can serve as a basis for incorporating generic ....

Chen W.: A theory of modules based on second-order logic. Proc. IEEE Symp. on Log. Progr., 1987, p. 24-33

....they are declared. Other methods may be exported to some specific classes, but not to all classes. While the idea of encapsulation is simple, its logical rendition is not. In [79] Miller suggested a way to represent modules in logic programming via the intuitionistic embedded implication. Chen [32] defines modules as second order objects, where data encapsulation inside modules is represented using existential quantifiers. In their present form, these approaches are not sufficiently general for use in F logic. It would be interesting to see, though, if these approaches can be extended to ....

....logic. We should also mention the recent work by Bugliesi and Jamil [26] While their language and the notion of encapsulation are more limited than ours, encapsulation is made part of the syntax, semantics, and the proof theory, which could be a promising direction in this area. In contrast to [32, 79, 26], we view various encapsulation mechanisms as no more than type correctness policies, albeit somewhat more elaborate than usual. This approach is quite general and it can model a wide variety of encapsulation mechanisms. Its other advantage is that it does not require extensions to the logic. ....

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W. Chen. A theory of modules based on second-order logic. In IEEE Symposium on Logic Programming (SLP), pages 24--33, September 1987.

....development. Two orthogonal directions of structuring can be observed in logic programming: modularization (structuring of programs) and sorting (structuring of data, i.e. grouping of individuals; sort type) As examples of research in the direction of modularization, we mention [Mil86] and [Che87]. In a number of studies, modules are viewed as worlds, with more or less explicit parallels drawn to the possible worlds semantics of modal logics. From among the merger systems, mentioned in Section 2.1, Prolog KR, Mandala and CPU take this approach. From proper modal extensions of Prolog, we ....

W. Chen. A theory of modules based on second-order logic. In Proc. 1987 Symp. on Logic Programming, San Fransisco, Aug/Sept 1987, pp 24-33. Washington, DC: IEEE Comp. Soc. Press, 1987.

....facilities to enhance modularity, readability and reusability of logic programs. This problem has been addressed in the literature using many different approaches (like the metalevel approach [6, 8] the algebraic approach [42, 30, 9] and the approach based on use of higher order logic [39, 12]) and, in particular, it has been tackled by extending the language of Horn clauses with implications embedded in goals, as proposed in [36, 38, 26, 25] see [11] for a survey of the different approaches) Languages with embedded implications have been extensively studied [22, 19, 34, 32] These ....

W. Chen. A theory of modules based on second order logic. In Proc. Symp. on Logic Programming, pages 24--33, S. Francisco, 1987.

....may be composed to yield flow analysis results for the entire program. We demonstrate this approach by giving a compositional ground dependencies analysis for modular logic programs. Semantic treatments of modules in logic programs have been given by a number of authors (see, for example, [7, 22]) typically based on nontrivial extensions to Horn clause logic that lead to complex semantics; it appears to us that the development of abstract interpretations based on such semantics is not entirely straightforward. The semantics we consider here as a basis for abstract interpretations is a ....

....to enable different notions of composition. Bossi et al. also consider clauses as semantic objects. They propose a bottom up approach providing a semantics that resembles the non ground TP operator of [14] Logical semantics for modules in logic programs have been proposed by a number of authors [7, 22]. These are typically based on various extensions to Horn logic: for example, Chen s treatment of modules [7] is based on second order logic, while Miller s [22] uses implication goals in clause bodies. In either case, the semantics appears to be somewhat more complicated than that considered in ....

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W. Chen. A Theory of Modules Based on SecondOrder Logic. In Proc. Fourth IEEE Int'l Symp. on Logic Programming, pp. 24--33. IEEE Comp. Soc. Press, 1987.

....of [14] per s e, 14] does present a calculus for incorporating functional abstraction, parameterization, etc. using program valued functions. The structural enhancements we presented also incorporate functional abstraction and parameterization, but using second order program constructs. Chen in [3] gives a theory of modules based on second order logic, but unlike his research, we don t give semantics for the second order representation of structural enhancement because eventually when structural enhancements are referred in program units, they are instantiated to first order constructs. 6 ....

Weidong Chen. A theory of modules based on second-order logic. In Proceedings of the Symposium on Logic Programming, pages 24--33. IEEE, IEEE Computer Society Press, 1987.

....As opposed to our language, the configuration of modules is strictly separated from the logic language itself. Context extension and the composition of logic theories have also been studied in [1] and [2] A third approach uses higher order features to incorporate modules into a logic language ([3], 4] The main contributions of this paper can be summarized as follows. ffl We define a deductive database language with modules and static scoping. A dynamic scoping rule can be invoked whenever desired, thus making a form of hypothetical reasoning possible. ffl Negation as Failure is ....

.... condition(X) oddint(X) lookup(NE,E) lookup(NO,O) evenint(X) integer(X) even(X) oddint(X) integer(X) odd(X) Count : countif( 0) countif( X L] s(N) condition(X) countif(L,N) countif( X L] N) not condition(X) countif(L,N) Sample Query : evenodd([1,2,3,4,5],E,O) Analyze, Table) Answer relation: f evenodd( 1,2,3,4,5] 2,3) g Figure 2: Sample programs Count and Analyze and sample query in basic syntax Let us assume for the moment, that we use a normal deductive database system, i.e. without embedded implications. At the top level, we can load the ....

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Chen W.: A theory of modules based on second-order logic, Proc. IEEE Symp. on Logic Programming, 1987

....may be composed to yield flow analysis results for the entire program. We demonstrate this approach by giving a compositional ground dependencies analysis for modular logic programs. Semantic treatments of modules in logic programs have been given by a number of authors (see, for example, [7,22]) typically based on nontrivial extensions to Horn clause logic that lead to complex semantics; it appears to us that the development of abstract interpretations based on such semantics is not entirely straightforward. The semantics we consider here as a basis for abstract interpretations is a ....

....to enable different notions of composition. Bossi et al. also consider clauses as semantic objects. They propose a bottom up approach providing a semantics that resembles the non ground TP operator of [14] Logical semantics for modules in logic programs have been proposed by a number of authors [7,22]. These are typically based on various extensions to Horn logic: for example, Chen s treatment of modules [7] is based on second order logic, while Miller s [22] uses implication goals in clause bodies. In either case, the semantics appears to be somewhat more complicated than that considered in ....

[Article contains additional citation context not shown here]

W. Chen. A Theory of Modules Based on SecondOrder Logic. In Proc. Fourth IEEE Int'l Symp. on Logic Programming, pp. 24--33. IEEE Comp. Soc. Press, 1987.

....programming. For example, Prolog combines predicate calculus, higher order and meta level programming in one working system, allowing programmers routine use of generic predicate definitions (e.g. transitive closure, sorting) where predicates can be passed as parameters and returned as values [7]. Another well known useful feature is the call meta predicate of Prolog. Applications of higher order constructs in the database context have been pointed out in many works, including [24, 29, 41] Although predicate calculus provides the basis for Prolog, it does not have the wherewithal to ....

....We propose a novel logic, called HiLog, which provides a clean declarative semantics to much of this higher order logic programming. From the outset, even the terminology of higher orderness seems ill defined. A number of works have proposed various higher order constructs in the logic framework [1, 5, 13, 7, 23, 24, 30, 31, 42, 45] but with such a diversity of syntax and semantics, it is not always clear what kind of higher orderness is being claimed. In our opinion, there are at least two different facets to the issue: a higher order This paper is an expanded version of the work previously reported in [10, 11] y ....

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Chen, W. [1987] A Theory of Modules Based on Second-Order Logic, in Proceedings of IEEE 1987 Symposium on Logic Programming, San Francisco, September, pp. 24--33.

....is to avoid name clashes between predicates used in different modules. The other is to represent a module definition as a logic formula. The latter requires a higher order framework since predicates can be passed as parameters and returned as results. The development, below, follows the outline of [3]. A program now consists of a finite set of clauses and a finite set of basic module definitions. Each basic module definition consists of a module interface and a body that contains a finite number of clauses. The concrete syntax of a module definition may be the following: closure(In; Out) f ....

....module definition may be the following: closure(In; Out) f Out(X; Y) Gamma In(X; Y) Out(X; Y) Gamma In(X; Z) Out(Z; Y) g Here, In is the input predicate variable, and Out is the variable exported by the module; it is instantiated to the transitive closure of In computed by the module. In [3], the above abstract syntax is given meaning using the following formula: 8In 9Out ( closure(In; Out) 8X8Y(Out(X; Y) Gamma In(Y; Y) 8X8Y8Z(Out(X; Y) Gamma In(X; Z) Out(Z; Y) 7) Notice that encapsulated predicates are represented by existential variables since only variables have ....

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W. Chen. A theory of modules based on second-order logic. In IEEE Symposium on Logic Programming (SLP), pages 24--33, September 1987.

No context found.

W. Chen. A theory of modules based on second-order logic. In Proc. 4th IEEE Internat. Symposium on Logic Programming, pages 24-33, San Francisco, 1987.

No context found.

W. Chen. A theory of modules based on second-order logic. In Proc. 4th IEEE Internat. Symposium on Logic Programming, pages 24-33, San Francisco, 1987.

No context found.

W. Chen. A Theory of Modules based on Second Order Logic. In Proc. of the Intenational Symposium on Logic Programming, ILPS'87, pages 24--33, S. Francisco, 1987.

No context found.

W. Chen. A theory of modules based on second-order logic. In Proceedings of the 1987 Symposium on Logic Programming, pages 24--33, San Francisco, September 1987.

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