src/ZF/ex/Acc.ML

   Otherwise acc(r) would be a proper class!    *)
 
 (*The intended introduction rule*)
 val prems = goal Acc.thy
     "[| !!b. <b,a>:r ==> b: acc(r);  a: field(r) |] ==> a: acc(r)";
-by (fast_tac (ZF_cs addIs ([e-mail])) 1);
+by (fast_tac (!claset addIs ([e-mail])) 1);
 qed "accI";
 
 goal Acc.thy "!!a b r. [| b: acc(r);  <a,b>: r |] ==> a: acc(r)";
 by (etac acc.elim 1);
-by (fast_tac ZF_cs 1);
+by (Fast_tac 1);
 qed "acc_downward";
 
 val [major,indhyp] = goal Acc.thy
     "[| a : acc(r);                                             \
 \       !!x. [| x: acc(r);  ALL y. <y,x>:r --> P(y) |] ==> P(x) \
 \    |] ==> P(a)";
 by (rtac (major RS acc.induct) 1);
 by (rtac indhyp 1);
-by (fast_tac ZF_cs 2);
+by (Fast_tac 2);
 by (resolve_tac acc.intrs 1);
 by (assume_tac 2);
 by (etac (Collect_subset RS Pow_mono RS subsetD) 1);
 qed "acc_induct";
 
 goal Acc.thy "wf[acc(r)](r)";
 by (rtac wf_onI2 1);
 by (etac acc_induct 1);
-by (fast_tac ZF_cs 1);
+by (Fast_tac 1);
 qed "wf_on_acc";
 
 (* field(r) <= acc(r) ==> wf(r) *)
 val acc_wfI = wf_on_acc RS wf_on_subset_A RS wf_on_field_imp_wf;
 

 by (rtac subsetI 1);
 by (etac (major RS wf_induct2) 1);
 by (rtac subset_refl 1);
 by (rtac accI 1);
 by (assume_tac 2);
-by (fast_tac ZF_cs 1);
+by (Fast_tac 1);
 qed "acc_wfD";
 
 goal Acc.thy "wf(r) <-> field(r) <= acc(r)";
 by (EVERY1 [rtac iffI, etac acc_wfD, etac acc_wfI]);
 qed "wf_acc_iff";