Demonic operators and monotype factors

  title={Demonic operators and monotype factors},
  author={Roland Carl Backhouse and Jaap van der Woude},
  journal={Mathematical Structures in Computer Science},
  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… 

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