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4 (* ||A|| A project by Andrea Asperti *)
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15 include "basic_2/rt_transition/rpx_lpx.ma".
16 include "basic_2/rt_transition/fpb.ma".
18 (* PARALLEL RST-TRANSITION FOR CLOSURES *************************************)
20 (* Properties with extended rt-transition for full local envs ***************)
22 (* Basic_2A1: uses: fpbq_lpx *)
23 lemma lpx_fpb (G) (T):
24 ∀L1,L2. ❪G,L1❫ ⊢ ⬈ L2 → ❪G,L1,T❫ ≽ ❪G,L2,T❫.
25 /3 width=1 by rpx_fpb, lpx_rpx/ qed.
27 lemma fpb_intro_req (G1) (G2) (L1) (L2) (T1) (T2):
28 ∀L0,L,T. ❪G1,L1,T1❫ ⬂⸮ ❪G2,L,T❫ → ❪G2,L❫ ⊢ T ⬈ T2 →
29 L ≡[T] L0 → ❪G2,L0❫ ⊢ ⬈ L2 → ❪G1,L1,T1❫ ≽ ❪G2,L2,T2❫.
30 /4 width=10 by fpb_intro, lpx_rpx, reqg_rpx_trans/ qed.
32 (* Inversion lemmas with extended rt-transition for full local envs *********)
34 lemma fpb_inv_req (G1) (G2) (L1) (L2) (T1) (T2):
35 ❪G1,L1,T1❫ ≽ ❪G2,L2,T2❫ →
36 ∃∃L0,L,T. ❪G1,L1,T1❫ ⬂⸮ ❪G2,L,T❫ & ❪G2,L❫ ⊢ T ⬈ T2 & L ≡[T] L0 & ❪G2,L0❫ ⊢ ⬈ L2.
37 #G1 #G2 #L1 #L2 #T1 #T2 * #L #T #H1 #HT2 #HL2
38 elim (rpx_inv_req_lpx … HL2) -HL2 #L0 #HL0 #HL02
39 /2 width=7 by ex4_3_intro/
42 (* Forward lemmas with extended rt-transition for full local envs ***********)
44 lemma fpb_fwd_req (G1) (G2) (L1) (L2) (T1) (T2):
45 ❪G1,L1,T1❫ ≽ ❪G2,L2,T2❫ →
46 ∃∃L0,L,T. ❪G1,L1,T1❫ ⬂⸮ ❪G2,L,T❫ & ❪G2,L❫ ⊢ T ⬈ T2 & ❪G2,L❫ ⊢ ⬈ L0 & L0 ≡[T] L2.
47 #G1 #G2 #L1 #L2 #T1 #T2 * #L #T #H1 #HT2 #HL2
48 elim (rpx_fwd_lpx_req … HL2) -HL2 #L0 #HL0 #HL02
49 /2 width=7 by ex4_3_intro/