matita/matita/contribs/lambdadelta/basic_2/etc/ygt/zgt.etc

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  14
  15 include "basic_2/computation/ltprs.ma".
  16 include "basic_2/dynamic/lsubsv.ma".
  17
  18 (* "BIG TREE" PROPER PARALLEL COMPUTATION FOR CLOSURES **********************)
  19
  20 axiom yprs: ∀h. sd h → bi_relation lenv term.
  21
  22 interpretation "'big tree' parallel computation (closure)"
  23    'BTPRedStar h g L1 T1 L2 T2 = (yprs h g L1 T1 L2 T2).
  24
  25 axiom cprs_yprs: ∀h,g,L,T1,T2. L ⊢ T1 ➡* T2 → h ⊢ ⦃L, T1⦄ ≥[g] ⦃L, T2⦄.
  26
  27 axiom sstas_yprs: ∀h,g,L,T1,T2. ⦃h, L⦄ ⊢ T1 •*[g] T2 →
  28                   h ⊢ ⦃L, T1⦄ ≥[g] ⦃L, T2⦄.
  29
  30 axiom lsubsv_yprs: ∀h,g,L1,L2,T. h ⊢ L2 ¡⊑[g] L1 → h ⊢ ⦃L1, T⦄ ≥[g] ⦃L2, T⦄.
  31
  32 axiom ltpr_cprs_yprs: ∀h,g,L1,L2,T1,T2. L1 ➡ L2 → L2 ⊢ T1 ➡* T2 →
  33                       h ⊢ ⦃L1, T1⦄ ≥[g] ⦃L2, T2⦄.
  34
  35 axiom ygt: ∀h. sd h → bi_relation lenv term.
  36
  37 interpretation "'big tree' proper parallel computation (closure)"
  38    'BTPRedStarProper h g L1 T1 L2 T2 = (ygt h g L1 T1 L2 T2).
  39
  40 axiom fw_ygt: ∀h,g,L1,L2,T1,T2. ♯{L2, T2} < ♯{L1, T1} → h ⊢ ⦃L1, T1⦄ >[g] ⦃L2, T2⦄.
  41
  42 axiom ygt_yprs_trans: ∀h,g,L1,L,L2,T1,T,T2. h ⊢ ⦃L1, T1⦄ >[g] ⦃L, T⦄ →
  43                       h ⊢ ⦃L, T⦄ ≥[g] ⦃L2, T2⦄ → h ⊢ ⦃L1, T1⦄ >[g] ⦃L2, T2⦄.