منابع مشابه
Inductive Data Types for Predicate Transformers
Modern functional programming languages 5, 6] and speciication formalisms 3] are built around the notion of inductive data types and homomorphisms on these data types. Such homomorphisms, which correspond to the familiar fold or reduce operators in functional programming, are called catamorphisms. In this note, it is shown how catamorphisms can be generalised from functions to relations, and fr...
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We study the underapproximation of the predicate transformers used to give semantics to the modalities in dynamic and temporal logic. Because predicate transformers operate on state sets, we define appropriate powerdomains for sound approximation. We study four such domains — two are based on “set inclusion” approximation, and two are based on “quantification” approximation — and we apply the d...
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We investigate laws for predicate transformers for the combination of nondeterministic choice and (extended) probabilistic choice, where predicates are taken to be functions to the extended nonnegative reals, or to closed intervals of such reals. These predicate transformers correspond to state transformers, which are functions to convex powerdomains, the appropriate powerdomains for the combin...
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The behavior of a program can be modeled by describing how it transforms input states to output states, the state transformer semantics. Alternatively, for verification purposes one is interested in a ’predicate transformer semantics’ which, for every condition on the output, yields the weakest precondition on the input that guarantees the desired property for the output. In the presence of com...
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The calculus of predicate transformers has proved fruitful for the derivation of state-transformation programs in conventional languages with general recursion and demonic nondeterminacy [8, 10, 11]. Derivations involving direct manipulation of predicates can be unwieldy, so it is hoped that the algebraic, program-level style [5] that has proved so successful in the simpler calculus of function...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1991
ISSN: 0304-3975
DOI: 10.1016/0304-3975(91)90029-2