matita/matita/contribs/lambdadelta/basic_2A/reduction/fpb_lift.ma

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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_2A/unfold/lstas_da.ma".
  16 include "basic_2A/reduction/cpx_lift.ma".
  17 include "basic_2A/reduction/fpb.ma".
  18
  19 (* "RST" PROPER PARALLEL COMPUTATION FOR CLOSURES ***************************)
  20
  21 (* Advanced properties ******************************************************)
  22
  23 lemma sta_fpb: ∀h,g,G,L,T1,T2,d. ⦃G, L⦄ ⊢ T1 ▪[h, g] d+1 →
  24                ⦃G, L⦄ ⊢ T1 •*[h, 1] T2 → ⦃G, L, T1⦄ ≻[h, g] ⦃G, L, T2⦄.
  25 #h #g #G #L #T1 #T2 #d #HT1 #HT12 elim (eq_term_dec T1 T2)
  26 /3 width=2 by fpb_cpx, sta_cpx/ #H destruct
  27 elim (lstas_inv_refl_pos h G L T2 0) //
  28 qed.