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16 lines
613 B
Text
16 lines
613 B
Text
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A user-defined connective may optionally be marked with a "cut".
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This serves to control backtracking much as in Prolog. MaGIC will
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not generate two models whose most significant difference is in
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a connective with a cut.
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Thus for example, where `A' is a primitive 0-adic connective and
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a rule
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A v ~A /
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has been added, MaGIC will normally generate failures of the law
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of the excluded middle. However, if `A' has been marked with a cut
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then MaGIC will generate models in which that law fails: if it
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fails for more than one element of a model, only the smallest such
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element will be reported.
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