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185
Proving Concurrent Constraint Programs Correct
, 1994
"... We develop a compositional proofsystem for the partial correctness of concurrent constraint programs. Soundness and (relative) completeness of the system are proved with respect to a denotational semantics based on the notion of strongest postcondition. The strongest postcondition semantics provide ..."
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Cited by 59 (14 self)
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We develop a compositional proofsystem for the partial correctness of concurrent constraint programs. Soundness and (relative) completeness of the system are proved with respect to a denotational semantics based on the notion of strongest postcondition. The strongest postcondition semantics provides a justification of the declarative nature of concurrent constraint programs, since it allows to view programs as theories in the specification logic. 1 Introduction Concurrent constraint programming ([24, 25, 26]) (ccp, for short) is a concurrent programming paradigm which derives from replacing the storeasvaluation conception of von Neumann computing by the storeas constraint model. Its computational model is based on a global store, represented by a constraint, which expresses some partial information on the values of the variables involved in the computation. The concurrent execution of different processes, which interact through the common store, refines the partial information of...
Presheaf Models for Concurrency
, 1999
"... In this dissertation we investigate presheaf models for concurrent computation. Our aim is to provide a systematic treatment of bisimulation for a wide range of concurrent process calculi. Bisimilarity is defined abstractly in terms of open maps as in the work of Joyal, Nielsen and Winskel. Their wo ..."
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Cited by 45 (19 self)
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In this dissertation we investigate presheaf models for concurrent computation. Our aim is to provide a systematic treatment of bisimulation for a wide range of concurrent process calculi. Bisimilarity is defined abstractly in terms of open maps as in the work of Joyal, Nielsen and Winskel. Their work inspired this thesis by suggesting that presheaf categories could provide abstract models for concurrency with a builtin notion of bisimulation. We show how
The Semantics of Grammar Formalisms Seen as Computer Languages
, 1984
"... The design, implementation, and use of grammar formalisms for natural language have constituted a major branch of computational linguistics throughout its development. By viewing gramn, ar formalisms as just a special cause of computer languages, we can take advantage of the machinery of dcnoationa ..."
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Cited by 43 (5 self)
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The design, implementation, and use of grammar formalisms for natural language have constituted a major branch of computational linguistics throughout its development. By viewing gramn, ar formalisms as just a special cause of computer languages, we can take advantage of the machinery of dcnoational semantics to provide a pre cise specification of their meaning. Using Dana Scott's domain theory, we elucidate the nature of the feature systems used in augmented phrasestructure grammar formalisms, in particular those of recent versions of generalized phrase structure grammar, lexical functional grammar and PATRI1, and provide a dcnotational semantics for a simple gram mar formalism. We find that the mathematical structures developed for this purpose contain an operation of feature generalization, not available in those grammar formalisms, that can be used to give a partial account of the effect of coordination on syntactic features.
Observable Sequentiality and Full Abstraction
 In Proceedings of POPL ’92
, 1992
"... ion Robert Cartwright Matthias Felleisen Department of Computer Science Rice University Houston, TX 772511892 Abstract One of the major challenges in denotational semantics is the construction of fully abstract models for sequential programming languages. For the past fifteen years, research o ..."
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Cited by 39 (5 self)
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ion Robert Cartwright Matthias Felleisen Department of Computer Science Rice University Houston, TX 772511892 Abstract One of the major challenges in denotational semantics is the construction of fully abstract models for sequential programming languages. For the past fifteen years, research on this problem has focused on developing models for PCF, an idealized functional programming language based on the typed lambda calculus. Unlike most practical languages, PCF has no facilities for observing and exploiting the evaluation order of arguments in procedures. Since we believe that such facilities are crucial for understanding the nature of sequential computation, this paper focuses on a sequential extension of PCF (called SPCF) that includes two classes of control operators: error generators and escape handlers. These new control operators enable us to construct a fully abstract model for SPCF that interprets higher types as sets of errorsensitive functions instead of continuous...
Generalized Semantics and Abstract Interpretation for Constraint Logic Programs
, 1995
"... We present a simple and powerful generalized algebraic semantics for constraint logic programs that is parameterized with respect to the underlying constraint system. The idea is to abstract away from standard semantic objects by focusing on the general properties of any possibly nonstandard ..."
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Cited by 38 (5 self)
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We present a simple and powerful generalized algebraic semantics for constraint logic programs that is parameterized with respect to the underlying constraint system. The idea is to abstract away from standard semantic objects by focusing on the general properties of any possibly nonstandard  semantic definition. In constraint logic programming, this corresponds to a suitable definition of the constraint system supporting the semantic definition. An algebraic structure is introduced to formalize the notion of a constraint system, thus making classical mathematical results applicable. Both topdown and bottomup semantics are considered. Nonstandard semantics for constraint logic programs can then be formally specified using the same techniques used to define standard semantics. Different nonstandard semantics for constraint logic languages can be specified in this ...
Domain Theoretic Models Of Polymorphism
, 1989
"... We give an illustration of a construction useful in producing and describing models of Girard and Reynolds' polymorphic calculus. The key unifying ideas are that of a Grothendieck fibration and the category of continuous sections associated with it, constructions used in indexed category theory; th ..."
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Cited by 34 (2 self)
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We give an illustration of a construction useful in producing and describing models of Girard and Reynolds' polymorphic calculus. The key unifying ideas are that of a Grothendieck fibration and the category of continuous sections associated with it, constructions used in indexed category theory; the universal types of the calculus are interpreted as the category of continuous sections of the fibration. As a major example a new model for the polymorphic calculus is presented. In it a type is interpreted as a Scott domain. In fact, understanding universal types of the polymorphic calculus as categories of continuous sections appears to be useful generally. For example, the technique also applies to the finitary projection model of Bruce and Longo, and a recent model of Girard. (Indeed the work here was inspired by Girard's and arose through trying to extend the construction of his model to Scott domains.) It is hoped that by pinpointing a key construction this paper will help towards...
Feature Logics
 HANDBOOK OF LOGIC AND LANGUAGE, EDITED BY VAN BENTHEM & TER MEULEN
, 1994
"... Feature logics form a class of specialized logics which have proven especially useful in classifying and constraining the linguistic objects known as feature structures. Linguistically, these structures have their origin in the work of the Prague school of linguistics, followed by the work of Chom ..."
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Cited by 33 (0 self)
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Feature logics form a class of specialized logics which have proven especially useful in classifying and constraining the linguistic objects known as feature structures. Linguistically, these structures have their origin in the work of the Prague school of linguistics, followed by the work of Chomsky and Halle in The Sound Pattern of English [16]. Feature structures have been reinvented several times by computer scientists: in the theory of data structures, where they are known as record structures, in artificial intelligence, where they are known as frame or slotvalue structures, in the theory of data bases, where they are called "complex objects", and in computati
A Generalized Semantics for Constraint Logic Programs
, 1992
"... We present a simple and powerful generalized algebraic semantics for constraint logic programs that is parameterized with respect to the underlying constraint system. "Generalized semantics" abstract away from standard semantics objects, by focusing on the general properties of any (possibly nonsta ..."
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Cited by 32 (13 self)
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We present a simple and powerful generalized algebraic semantics for constraint logic programs that is parameterized with respect to the underlying constraint system. "Generalized semantics" abstract away from standard semantics objects, by focusing on the general properties of any (possibly nonstandard) semantics definition. In constraint logic programming, this corresponds to a suitable definition of the constraint system supporting the semantics definition. An algebraic structure is introduced to formalize the constraint system notion, thus making applicable classical mathematical results and both a topdown and bottomup semantics are considered. Nonstandard semantics for CLP can then be formally specified by means of the same techniques used to define standard semantics. Different nonstandard semantics for constraint logic languages can be specified in this framework: e.g. abstract interpretation, machine level traces and any computation based on an instance of the constraint system.
Extensible Denotational Language Specifications
 SYMPOSIUM ON THEORETICAL ASPECTS OF COMPUTER SOFTWARE, NUMBER 789 IN LNCS
, 1994
"... Traditional denotational semantics assigns radically different meanings to one and the same phrase depending on the rest of the programming language. If the language is purely functional, the denotation of a numeral is a function from environments to integers. But, in a functional language with impe ..."
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Cited by 32 (5 self)
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Traditional denotational semantics assigns radically different meanings to one and the same phrase depending on the rest of the programming language. If the language is purely functional, the denotation of a numeral is a function from environments to integers. But, in a functional language with imperative control operators, a numeral denotes a function from environments and continuations to integers. This paper introduces a new format for denotational language specifications, extended direct semantics, that accommodates orthogonal extensions of a language without changing the denotations of existing phrases. An extended direct semantics always maps a numeral to the same denotation: the injection of the corresponding number into the domain of values. In general, the denotation of a phrase in a functional language is always a projection of the denotation of the same phrase in the semantics of an extended languageno matter what the extension is. Based on extended direct semantics, i...