# Demonic operators and monotype factors

@article{Backhouse1993DemonicOA, title={Demonic operators and monotype factors}, author={Roland Carl Backhouse and Jaap van der Woude}, journal={Mathematical Structures in Computer Science}, year={1993}, volume={3}, pages={417 - 433} }

This paper tackles the problem of constructing a compact, point-free proof of the associativity of demonic composition of binary relations and its distributivity through demonic choice. In order to achieve this goal, a definition of demonic composition is proposed in which angelic composition is restricted by means of a so-called ‘monotype factor’. Monotype factors are characterised by a Galois connection similar to the Galois connection between composition and factorisation of binary relations…

## 70 Citations

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This paper presents a proof of the associativity of demonic composition of relations in Dedekind categories and shows that the demonic composition is monotonic with respect to two demonic orderings…

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In this paper, we show that the operational semantics of a nondeterministic while loop give in previous paper is equal to the denotational one, which is given as the greatest fixed point of the…

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