src/HOL/UNITY/Common.thy
changeset 4776 1f9362e769c1
child 5277 e4297d03e5d2
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/HOL/UNITY/Common.thy	Fri Apr 03 12:34:33 1998 +0200
     1.3 @@ -0,0 +1,32 @@
     1.4 +(*  Title:      HOL/UNITY/Common
     1.5 +    ID:         $Id$
     1.6 +    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
     1.7 +    Copyright   1998  University of Cambridge
     1.8 +
     1.9 +Common Meeting Time example from Misra (1994)
    1.10 +
    1.11 +The state is identified with the one variable in existence.
    1.12 +
    1.13 +From Misra, "A Logic for Concurrent Programming" (1994), sections 5.1 and 13.1.
    1.14 +*)
    1.15 +
    1.16 +Common = WFair +
    1.17 +
    1.18 +consts
    1.19 +  ftime,gtime :: nat=>nat
    1.20 +
    1.21 +rules
    1.22 +  fmono "m <= n ==> ftime m <= ftime n"
    1.23 +  gmono "m <= n ==> gtime m <= gtime n"
    1.24 +
    1.25 +  fasc  "m <= ftime n"
    1.26 +  gasc  "m <= gtime n"
    1.27 +
    1.28 +constdefs
    1.29 +  common :: nat set
    1.30 +    "common == {n. ftime n = n & gtime n = n}"
    1.31 +
    1.32 +  maxfg :: nat => nat set
    1.33 +    "maxfg m == {t. t <= max (ftime m) (gtime m)}"
    1.34 +
    1.35 +end