--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* STATO: NON COMPILA: dev'essere aggiornato *)
+
+set "baseuri" "cic:/matita/PREDICATIVE-TOPOLOGY/class_eq".
+
+include "class_defs.ma".
+
+theorem ceq_trans: \forall C. \xforall c1,c2. ceq C c1 c2 \to
+ \xforall c3. ceq ? c2 c3 \to ceq ? c1 c3.
+intros.
+
+(*
+apply ceq_intro; apply cle_trans; [|auto new timeout=100|auto new timeout=100||auto new timeout=100|auto new timeout=100].
+qed.
+
+theorem ceq_sym: \forall C,c1,c2. ceq C c1 c2 \to ceq C c2 c1.
+intros; elim H; clear H.; auto new timeout=100.
+qed.
+*)