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15 include "basic_2/dynamic/snv_fpr.ma".
17 (* STRATIFIED NATIVE VALIDITY FOR TERMS *************************************)
19 (* Properties on context-free parallel computation for closures *************)
21 fact ssta_fprs_aux: ∀h,g,n. (
23 ∀T1. L ⊢ T1 ⬌* T2 → ⦃h, L⦄ ⊩ T1 :[g] → ⦃h, L⦄ ⊩ T2 :[g] →
24 ∀U1,l1. ⦃h, L⦄ ⊢ T1 •[g, l1] U1 →
25 ∀U2,l2. ⦃h, L⦄ ⊢ T2 •[g, l2] U2 →
26 L ⊢ U1 ⬌* U2 ∧ l1 = l2
28 ∀L,T. ♯{L,T} < n → ⦃h, L⦄ ⊩ T :[g] →
29 ∀U. ⦃h, L⦄ ⊢ T •*➡*[g] U → ⦃h, L⦄ ⊩ U :[g]
31 ∀L1,T1. ♯{L1,T1} < n →
32 ∀U1,l. ⦃h, L1⦄ ⊢ T1 •[g, l] U1 →
33 ∀L2,T2. ⦃L1, T1⦄ ➡* ⦃L2, T2⦄ → ⦃h, L1⦄ ⊩ T1 :[g] →
34 ∃∃U2. ⦃h, L2⦄ ⊢ T2 •[g, l] U2 & ⦃L1, U1⦄ ⬌* ⦃L2, U2⦄
36 ∀L1,T1. ♯{L1,T1} = n →
37 ∀U1,l. ⦃h, L1⦄ ⊢ T1 •[g, l] U1 →
38 ∀L2,T2. ⦃L1, T1⦄ ➡* ⦃L2, T2⦄ → ⦃h, L1⦄ ⊩ T1 :[g] →
39 ∃∃U2. ⦃h, L2⦄ ⊢ T2 •[g, l] U2 & ⦃L1, U1⦄ ⬌* ⦃L2, U2⦄.
40 #h #g #n #IH3 #IH2 #IH1 #L1 #T1 #Hn #U1 #l #HTU1 #L2 #T2 #H12 #HT1
41 @(fprs_ind … H12) -L2 -T2 [-IH1 /2 width=3/ ] (**) (* auto fails without -IH1 *)
42 #L #L2 #T #T2 #HT1 #HT2 * #U #HTU #HU1
46 elim (ssta_fpr_aux … IH3 … Hn … HTU1 … HT2 HT1)
47 -T1 -IH3 -IH2 -HL1 [2: /3 width=5/ ] -n #U #HTU #HU1