| author | nipkow | 
| Thu, 26 Nov 1998 12:18:08 +0100 | |
| changeset 5974 | 6acf3ff0f486 | 
| parent 4833 | 2e53109d4bc8 | 
| permissions | -rw-r--r-- | 
| 3664 | 1  | 
(* Title: HOLCF/IMP/HoareEx.ML  | 
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ID: $Id$  | 
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Author: Tobias Nipkow  | 
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Copyright 1997 TUM  | 
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Correctness of while-loop.  | 
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*)  | 
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val prems = goalw thy [hoare_valid_def]  | 
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"|= {A} c {A} ==> |= {A} WHILE b DO c {%s. A s & ~b s}";
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by (cut_facts_tac prems 1);  | 
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by (Simp_tac 1);  | 
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by (rtac fix_ind 1);  | 
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(* simplifier with enhanced adm-tactic: *)  | 
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by (Simp_tac 1);  | 
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by (Simp_tac 1);  | 
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by (Simp_tac 1);  | 
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by (Blast_tac 1);  | 
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qed "WHILE_rule_sound";  |