matita/matita/contribs/lambda_delta/basic_2/static/aaa_lifts.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
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   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/unfold/ldrops.ma".
  16 include "basic_2/static/aaa_lift.ma".
  17
  18 (* ATONIC ARITY ASSIGNMENT ON TERMS *****************************************)
  19
  20 (* Properties concerning generic relocation *********************************)
  21
  22 lemma aaa_lifts: ∀L1,L2,T2,A,des. ⇩*[des] L2 ≡ L1 → ∀T1. ⇧*[des] T1 ≡ T2 →
  23                                   L1 ⊢ T1 ⁝ A →  L2 ⊢ T2 ⁝ A.
  24 #L1 #L2 #T2 #A #des #H elim H -L1 -L2 -des
  25 [ #L #T1 #H #HT1
  26   <(lifts_inv_nil … H) -H //
  27 | #L1 #L #L2 #des #d #e #_ #HL2 #IHL1 #T1 #H #HT1
  28   elim (lifts_inv_cons … H) -H /3 width=9/
  29 ]
  30 qed.