thys/RegLangs.thy
changeset 314 20a57552d722
parent 311 8b8db9558ecf
child 359 fedc16924b76
equal deleted inserted replaced
313:3b8e3a156200 314:20a57552d722
   191 
   191 
   192 lemma ders_append:
   192 lemma ders_append:
   193   shows "ders (s1 @ s2) r = ders s2 (ders s1 r)"
   193   shows "ders (s1 @ s2) r = ders s2 (ders s1 r)"
   194   by (induct s1 arbitrary: s2 r) (auto)
   194   by (induct s1 arbitrary: s2 r) (auto)
   195 
   195 
   196 
   196 lemma ders_snoc:
       
   197   shows "ders (s @ [c]) r = der c (ders s r)"
       
   198   by (simp add: ders_append)
   197 
   199 
   198 end
   200 end