src/HOL/WF.ML
changeset 6433 228237ec56e5
parent 5579 32f99ca617b7
child 6814 d96d4977f94e
equal deleted inserted replaced
6432:cdde45202c5c 6433:228237ec56e5
   233 
   233 
   234 Goalw [acyclic_def] "acyclic(r^-1) = acyclic r";
   234 Goalw [acyclic_def] "acyclic(r^-1) = acyclic r";
   235 by (simp_tac (simpset() addsimps [trancl_converse]) 1);
   235 by (simp_tac (simpset() addsimps [trancl_converse]) 1);
   236 qed "acyclic_converse";
   236 qed "acyclic_converse";
   237 
   237 
       
   238 Goalw [acyclic_def] "[| acyclic s; r <= s |] ==> acyclic r";
       
   239 by(blast_tac (claset() addIs [trancl_mono]) 1);
       
   240 qed "acyclic_subset";
       
   241 
   238 (** cut **)
   242 (** cut **)
   239 
   243 
   240 (*This rewrite rule works upon formulae; thus it requires explicit use of
   244 (*This rewrite rule works upon formulae; thus it requires explicit use of
   241   H_cong to expose the equality*)
   245   H_cong to expose the equality*)
   242 Goalw [cut_def]
   246 Goalw [cut_def]