src/HOL/Tools/inductive_set.ML

            handle Subscript => error "infer_arities: bad term")
     | _ => fold (infer_arities thy arities) (map (pair NONE) ts)
       (case optf of
          NONE => fs
        | SOME f => AList.update op = (u, the_default f
-           (Option.map (curry (gen_inter (op =)) f) (AList.lookup op = fs u))) fs));
+           (Option.map (curry (inter (op =)) f) (AList.lookup op = fs u))) fs));
 
 
 (**************************************************************)
 (*    derive the to_pred equation from the to_set equation    *)
 (*                                                            *)