matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpm_tdeq.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 "static_2/syntax/tdeq.ma".
  16 include "basic_2/rt_transition/cpm_drops.ma".
  17
  18 (* T-BOUND CONTEXT-SENSITIVE PARALLEL RT-TRANSITION FOR TERMS ***************)
  19
  20 (* Inversion lemmas with degree-based equivalence for terms *****************)
  21
  22 lemma cpm_tdeq_inv_lref (n) (h) (o) (G) (L) (i):
  23                         ∀X.  ⦃G, L⦄ ⊢ #i ➡[n,h] X → #i ≛[h,o] X →
  24                         ∧∧ X = #i & n = 0.
  25 #n #h #o #G #L #i #X #H1 #H2
  26 lapply (tdeq_inv_lref1 … H2) -H2 #H destruct
  27 elim (cpm_inv_lref1_drops … H1) -H1 // * [| #m ]
  28 #K #V1 #V2 #_ #_ #H -V1
  29 elim (lifts_inv_lref2_uni_lt … H) -H //
  30 qed-.