matita/matita/contribs/lambdadelta/basic_2/dynamic/cnv_cpme.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 "basic_2/rt_computation/cprs_cnr.ma".
  16 include "basic_2/rt_computation/cpre.ma".
  17 include "basic_2/dynamic/cnv_preserve.ma".
  18
  19 (* CONTEXT-SENSITIVE NATIVE VALIDITY FOR TERMS ******************************)
  20
  21 (* Properties with evaluation for t-bound rt-transition on terms ************)
  22
  23 lemma cnv_cpme_cpms_conf (a) (h) (n) (G) (L):
  24       ∀T. ⦃G,L⦄ ⊢ T ![a,h] → ∀T1. ⦃G,L⦄ ⊢ T ➡*[n,h] T1 →
  25       ∀T2. ⦃G,L⦄ ⊢ T ➡*[h,n] 𝐍⦃T2⦄ → ⦃G,L⦄ ⊢ T1 ➡*[h] 𝐍⦃T2⦄.
  26 #a #h #n #G #L #T0 #HT0 #T1 #HT01 #T2 * #HT02 #HT2
  27 elim (cnv_cpms_conf … HT0 … HT01 … HT02) -T0 <minus_n_n #T0 #HT10 #HT20
  28 lapply (cprs_inv_cnr_sn … HT20 HT2) -HT20 #H destruct
  29 /2 width=1 by conj/
  30 qed-.