Semantics of Quasi-Boolean Expressions

  • A. Bijlsma
Part of the Texts and Monographs in Computer Science book series (MCS)


In deriving programs, it is often useful to consider certain expressions as well-defined although they contain subexpressions to which no value can reasonably be attributed. For instance, one wishes to consider the expression
$$ 0 \leqslant i < n and a\left[ i \right] = 0 $$
as false when i = n, without worrying whether or not n is in the subscript range of array a. Expressions like these are called quasi-boolean in [3]. Traditionally, they are treated by introducing the conditional connectives cand and cor [2, chapter 4] [4, §4.1].




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Copyright information

© Springer-Verlag New York, Inc. 1990

Authors and Affiliations

  • A. Bijlsma
    • 1
  1. 1.Department of Mathematics and Computing ScienceEindhoven University of TechnologyEindhovenThe Netherlands

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