src/FOL/ex/Miniscope.thy
changeset 60770 240563fbf41d
parent 59498 50b60f501b05
child 61489 b8d375aee0df
--- a/src/FOL/ex/Miniscope.thy	Thu Jul 23 14:20:51 2015 +0200
+++ b/src/FOL/ex/Miniscope.thy	Thu Jul 23 14:25:05 2015 +0200
@@ -14,9 +14,9 @@
 
 lemmas ccontr = FalseE [THEN classical]
 
-subsection {* Negation Normal Form *}
+subsection \<open>Negation Normal Form\<close>
 
-subsubsection {* de Morgan laws *}
+subsubsection \<open>de Morgan laws\<close>
 
 lemma demorgans:
   "~(P&Q) <-> ~P | ~Q"
@@ -38,7 +38,7 @@
 
 (* BEWARE: rewrite rules for <-> can confuse the simplifier!! *)
 
-subsubsection {* Pushing in the existential quantifiers *}
+subsubsection \<open>Pushing in the existential quantifiers\<close>
 
 lemma ex_simps:
   "(EX x. P) <-> P"
@@ -50,7 +50,7 @@
   by blast+
 
 
-subsubsection {* Pushing in the universal quantifiers *}
+subsubsection \<open>Pushing in the universal quantifiers\<close>
 
 lemma all_simps:
   "(ALL x. P) <-> P"
@@ -63,10 +63,10 @@
 
 lemmas mini_simps = demorgans nnf_simps ex_simps all_simps
 
-ML {*
+ML \<open>
 val mini_ss = simpset_of (@{context} addsimps @{thms mini_simps});
 fun mini_tac ctxt =
   resolve_tac ctxt @{thms ccontr} THEN' asm_full_simp_tac (put_simpset mini_ss ctxt);
-*}
+\<close>
 
 end