1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 include "static_2/syntax/teq.ma".
17 (* SYNTACTIC EQUIVALENCE ON TERMS *******************************************)
19 (* Main forward properties **************************************************)
23 /2 width=3 by teq_repl_1/ qed-.
25 theorem teq_repl_2 (R):
26 replace_2 … R teq teq.
27 #R #T1 #U1 #HTU1 #T2 #HT12 #U2 #HU12
28 <(teq_inv_eq … HT12) -T2 <(teq_inv_eq … HU12) -U2 //