X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fstatic%2Flfdeq_length.ma;h=8221e2ed86e2c128430ccf7fdae7e20dff5a8b87;hb=c879284b576409cec07e96c1f08510d9d9ac14f3;hp=aafc792212195f92d80d600f689478cc581976fd;hpb=e11ce46390f264e9010157dd36c0b9e71a58ba4b;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_length.ma b/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_length.ma
index aafc79221..8221e2ed8 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_length.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/static/lfdeq_length.ma
@@ -12,6 +12,7 @@
 (*                                                                        *)
 (**************************************************************************)
 
+include "basic_2/relocation/lifts_tdeq.ma".
 include "basic_2/static/lfxs_length.ma".
 include "basic_2/static/lfdeq.ma".
 
@@ -22,3 +23,11 @@ include "basic_2/static/lfdeq.ma".
 (* Basic_2A1: lleq_fwd_length *)
 lemma lfdeq_fwd_length: ∀h,o,L1,L2. ∀T:term. L1 ≡[h, o, T] L2 → |L1| = |L2|.
 /2 width=3 by lfxs_fwd_length/ qed-.
+
+(* Properties with length for local environments ****************************)
+
+(* Basic_2A1: uses: lleq_lift_le lleq_lift_ge *)
+lemma lfdeq_lifts_bi: ∀L1,L2. |L1| = |L2| → ∀h,o,K1,K2,T. K1 ≡[h, o, T] K2 →
+                      ∀b,f. ⬇*[b, f] L1 ≡ K1 → ⬇*[b, f] L2 ≡ K2 →
+                      ∀U. ⬆*[f] T ≡ U → L1 ≡[h, o, U] L2.
+/3 width=9 by lfxs_lifts_bi, tdeq_lifts_sn/ qed-.