--- a/src/HOL/IMP/Hoare.thy Mon May 27 07:44:10 2013 +0200
+++ b/src/HOL/IMP/Hoare.thy Mon May 27 09:15:26 2013 +0200
@@ -10,7 +10,7 @@
definition
hoare_valid :: "assn \<Rightarrow> com \<Rightarrow> assn \<Rightarrow> bool" ("\<Turnstile> {(1_)}/ (_)/ {(1_)}" 50) where
-"\<Turnstile> {P}c{Q} = (\<forall>s t. (c,s) \<Rightarrow> t \<longrightarrow> P s \<longrightarrow> Q t)"
+"\<Turnstile> {P}c{Q} = (\<forall>s t. P s \<and> (c,s) \<Rightarrow> t \<longrightarrow> Q t)"
abbreviation state_subst :: "state \<Rightarrow> aexp \<Rightarrow> vname \<Rightarrow> state"
("_[_'/_]" [1000,0,0] 999)