update in delayed_updating

[helm.git] / matita / matita / contribs / lambdadelta / delayed_updating / unwind / unwind2_path_lift.ma

diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/unwind/unwind2_path_lift.ma b/matita/matita/contribs/lambdadelta/delayed_updating/unwind/unwind2_path_lift.ma
new file mode 100644 (file)
index 0000000..642056c
--- /dev/null
+++ b/matita/matita/contribs/lambdadelta/delayed_updating/unwind/unwind2_path_lift.ma
@@ -0,0 +1,31 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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 "delayed_updating/unwind/unwind2_path_eq.ma".
+include "delayed_updating/substitution/lift_eq.ma".
+include "ground/relocation/tr_uni_compose.ma".
+
+(* UNWIND FOR PATH **********************************************************)
+
+(* Properties with lift_path ************************************************)
+
+lemma unwind2_lift_path_after (p) (f1) (f2):
+      ↑[f2]▼[f1]p = ▼[f2∘f1]p.
+#p @(path_ind_unwind … p) -p // [ #n | #p ] #IH #f1 #f2
+[ <unwind2_path_d_empty <unwind2_path_d_empty
+  <lift_path_d_sn <lift_path_empty //
+| <unwind2_path_L_sn <unwind2_path_L_sn <lift_path_L_sn
+  >tr_compose_push_bi //
+]
+qed.