src/HOL/IMP/Natural.ML
author nipkow
Tue Apr 08 10:48:42 1997 +0200 (1997-04-08)
changeset 2919 953a47dc0519
parent 1973 8c94c9a5be10
child 4089 96fba19bcbe2
permissions -rw-r--r--
Dep. on Provers/nat_transitive
     1 (*  Title:      HOL/IMP/Natural.ML
     2     ID:         $Id$
     3     Author:     Tobias Nipkow & Larry Paulson, TUM
     4     Copyright   1996 TUM
     5 *)
     6 
     7 open Natural;
     8 
     9 AddIs evalc.intrs;
    10 
    11 val evalc_elim_cases = map (evalc.mk_cases com.simps)
    12    ["<SKIP,s> -c-> t", "<x:=a,s> -c-> t", "<c1;c2, s> -c-> t",
    13     "<IF b THEN c1 ELSE c2, s> -c-> t"];
    14 
    15 val evalc_WHILE_case = evalc.mk_cases com.simps "<WHILE b DO c,s> -c-> t";
    16 
    17 AddSEs evalc_elim_cases;
    18 
    19 (* evaluation of com is deterministic *)
    20 goal Natural.thy "!!c s t. <c,s> -c-> t ==> (!u. <c,s> -c-> u --> u=t)";
    21 by (etac evalc.induct 1);
    22 by (thin_tac "<?c,s2> -c-> s1" 7);
    23 by (ALLGOALS (deepen_tac (!claset addEs [evalc_WHILE_case]) 4));
    24 qed_spec_mp "com_det";