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(* Title: HOL/UNITY/Common
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ID: $Id$
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Author: Lawrence C Paulson, Cambridge University Computer Laboratory
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Copyright 1998 University of Cambridge
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Common Meeting Time example from Misra (1994)
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The state is identified with the one variable in existence.
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From Misra, "A Logic for Concurrent Programming" (1994), sections 5.1 and 13.1.
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*)
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7537
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Common = Union +
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4776
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consts
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ftime,gtime :: nat=>nat
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rules
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fmono "m <= n ==> ftime m <= ftime n"
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gmono "m <= n ==> gtime m <= gtime n"
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fasc "m <= ftime n"
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gasc "m <= gtime n"
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constdefs
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common :: nat set
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"common == {n. ftime n = n & gtime n = n}"
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maxfg :: nat => nat set
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"maxfg m == {t. t <= max (ftime m) (gtime m)}"
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end
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