update in basic_2

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / static / ffdeq_lfeq.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/static/ffdeq_lfeq.ma b/matita/matita/contribs/lambdadelta/basic_2/static/ffdeq_lfeq.ma
new file mode 100644 (file)
index 0000000..e0453bf
--- /dev/null
+++ b/matita/matita/contribs/lambdadelta/basic_2/static/ffdeq_lfeq.ma
@@ -0,0 +1,27 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+include "basic_2/static/lfdeq_lfeq.ma".
+include "basic_2/static/ffdeq.ma".
+
+(* DEGREE-BASED EQUIVALENCE FOR CLOSURES ON REFERRED ENTRIES ****************)
+
+(* Properties with syntactic equivalence on referred entries ****************)
+
+lemma lfeq_lfdeq_trans: ∀h,o,L1,L,T1. L1 ≐[T1] L →
+                        ∀G1,G2,L2,T2. ⦃G1, L, T1⦄ ≛[h, o] ⦃G2, L2, T2⦄ → ⦃G1, L1, T1⦄ ≛[h, o] ⦃G2, L2, T2⦄.
+#h #o #L1 #L #T1 #HL1 #G1 #G2 #L2 #T2 #H
+elim (ffdeq_inv_gen_sn … H) -H #H #HL2 #T12 destruct
+/3 width=3 by ffdeq_intro_sn, lfeq_lfdeq_trans/
+qed-.