update in lambdadelta

[helm.git] / matita / matita / contribs / lambdadelta / basic_2A / reduction / fpb_lift.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2A/reduction/fpb_lift.ma b/matita/matita/contribs/lambdadelta/basic_2A/reduction/fpb_lift.ma
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+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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_2A/unfold/lstas_da.ma".
+include "basic_2A/reduction/cpx_lift.ma".
+include "basic_2A/reduction/fpb.ma".
+
+(* "RST" PROPER PARALLEL COMPUTATION FOR CLOSURES ***************************)
+
+(* Advanced properties ******************************************************)
+
+lemma sta_fpb: ∀h,g,G,L,T1,T2,d. ⦃G, L⦄ ⊢ T1 ▪[h, g] d+1 →
+               ⦃G, L⦄ ⊢ T1 •*[h, 1] T2 → ⦃G, L, T1⦄ ≻[h, g] ⦃G, L, T2⦄.
+#h #g #G #L #T1 #T2 #d #HT1 #HT12 elim (eq_term_dec T1 T2)
+/3 width=2 by fpb_cpx, sta_cpx/ #H destruct
+elim (lstas_inv_refl_pos h G L T2 0) //
+qed.