Chorus Angelorum

  • Steve Dunne
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4355)


We extend B’s GSL by introducing new operators for angelic choice, thus widening its application from its original domain of conjunctive computations to that of monotonic ones in general. We explore the impact of this on our theory of substitutions [6], discovering two dual new normal forms for our new substitutions which we exploit to formulate two new first-order tests of refinement between them.


Normal Form Generalise Substitution Predicate Transformer Conjunctive Computation Frame Enlargement 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Steve Dunne
    • 1
  1. 1.School of ComputingUniversity of TeessideMiddlesbroughUK

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