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15 include "basic_2/multiple/fleq.ma".
16 include "basic_2/reduction/fpb_lleq.ma".
18 (* "RST" PROPER PARALLEL COMPUTATION FOR CLOSURES ***************************)
20 (* Properties on lazy equivalence for closures ******************************)
22 lemma fleq_fpb_trans: ∀h,o,F1,F2,K1,K2,T1,T2. ⦃F1, K1, T1⦄ ≡[0] ⦃F2, K2, T2⦄ →
23 ∀G2,L2,U2. ⦃F2, K2, T2⦄ ≻[h, o] ⦃G2, L2, U2⦄ →
24 ∃∃G1,L1,U1. ⦃F1, K1, T1⦄ ≻[h, o] ⦃G1, L1, U1⦄ & ⦃G1, L1, U1⦄ ≡[0] ⦃G2, L2, U2⦄.
25 #h #o #F1 #F2 #K1 #K2 #T1 #T2 * -F2 -K2 -T2
26 #K2 #HK12 #G2 #L2 #U2 #H12 elim (lleq_fpb_trans … HK12 … H12) -K2
27 /3 width=5 by fleq_intro, ex2_3_intro/
30 (* Inversion lemmas on lazy equivalence for closures ************************)
32 lemma fpb_inv_fleq: ∀h,o,G1,G2,L1,L2,T1,T2. ⦃G1, L1, T1⦄ ≻[h, o] ⦃G2, L2, T2⦄ →
33 ⦃G1, L1, T1⦄ ≡[0] ⦃G2, L2, T2⦄ → ⊥.
34 #h #o #G1 #G2 #L1 #L2 #T1 #T2 * -G2 -L2 -T2
35 [ #G2 #L2 #T2 #H12 #H elim (fleq_inv_gen … H) -H
36 /3 width=8 by lleq_fwd_length, fqu_inv_eq/
37 | #T2 #_ #HnT #H elim (fleq_inv_gen … H) -H /2 width=1 by/
38 | #L2 #_ #HnL #H elim (fleq_inv_gen … H) -H /2 width=1 by/