matita/matita/contribs/lambdadelta/static_2/syntax/teq_teq.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
   7 (*      ||T||         The HELM team.                                      *)
   8 (*      ||A||         http://helm.cs.unibo.it                             *)
   9 (*      \   /                                                             *)
  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
  12 (*                                                                        *)
  13 (**************************************************************************)
  14
  15 include "static_2/syntax/teq.ma".
  16
  17 (* SYNTACTIC EQUIVALENCE ON TERMS *******************************************)
  18
  19 (* Main forward properties **************************************************)
  20
  21 theorem teq_trans:
  22         Transitive … teq.
  23 /2 width=3 by teq_repl_1/ qed-.
  24 (*
  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 //
  29 qed-.
  30 *)