| author | wenzelm |
| Tue, 05 Jun 2018 00:06:23 +0200 | |
| changeset 68378 | 22680a3f8346 |
| parent 42154 | 478bdcea240a |
| child 72990 | db8f94656024 |
| permissions | -rw-r--r-- |
| 13857 | 1 |
(* Title: HOL/Hoare/ExamplesAbort.thy |
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Author: Tobias Nipkow |
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Copyright 1998 TUM |
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Some small examples for programs that may abort. |
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*) |
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35316
870dfea4f9c0
dropped axclass; dropped Id; session theory Hoare.thy
haftmann
parents:
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changeset
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theory ExamplesAbort imports Hoare_Logic_Abort begin |
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lemma "VARS x y z::nat |
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{y = z & z \<noteq> 0} z \<noteq> 0 \<rightarrow> x := y div z {x = 1}"
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by vcg_simp |
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lemma |
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"VARS a i j |
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{k <= length a & i < k & j < k} j < length a \<rightarrow> a[i] := a!j {True}"
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by vcg_simp |
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lemma "VARS (a::int list) i |
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{True}
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i := 0; |
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WHILE i < length a |
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INV {i <= length a}
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DO a[i] := 7; i := i+1 OD |
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{True}"
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by vcg_simp |
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end |