matita/matita/contribs/lambdadelta/basic_2/dynamic/lsubsv_ssta.ma

   1 (**************************************************************************)
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   3 (*      ||M||                                                             *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
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  14
  15 include "basic_2/equivalence/lsubss_ssta.ma".
  16 include "basic_2/dynamic/lsubsv.ma".
  17
  18 (* LOCAL ENVIRONMENT REFINEMENT FOR STRATIFIED NATIVE VALIDITY **************)
  19
  20 (* Properties on stratified static type assignment **************************)
  21
  22 lemma lsubsv_ssta_trans: ∀h,g,L2,T,U2,l. ⦃h, L2⦄ ⊢ T •[g] ⦃l, U2⦄ →
  23                          ∀L1. h ⊢ L1 ⊩:⊑[g] L2 →
  24                          ∃∃U1. ⦃h, L1⦄ ⊢ T •[g] ⦃l, U1⦄ & L1 ⊢ U1 ⬌* U2.
  25 /3 width=3 by lsubsv_fwd_lsubss, lsubss_ssta_trans/
  26 qed-.