+++ /dev/null
-(**************************************************************************)
-(* ___ *)
-(* ||M|| *)
-(* ||A|| A project by Andrea Asperti *)
-(* ||T|| *)
-(* ||I|| Developers: *)
-(* ||T|| The HELM team. *)
-(* ||A|| http://helm.cs.unibo.it *)
-(* \ / *)
-(* \ / This file is distributed under the terms of the *)
-(* v GNU General Public License Version 2 *)
-(* *)
-(**************************************************************************)
-
-include "basic_2/substitution/llneq_alt.ma".
-include "basic_2/computation/lpxs_ldrop.ma".
-include "basic_2/computation/lpxs_cpxs.ma".
-
-(* SN EXTENDED PARALLEL COMPUTATION FOR LOCAL ENVIRONMENTS ******************)
-
-(* Forward lemmas on negated lazy equivalence for local environments ********)
-
-lemma lpxs_llneq_fwd_cpxs: ∀h,g,G,L1,L2,T,d. L1 ⧣⧣[T, d] L2 → ⦃G, L1⦄ ⊢ ➡*[h, g] L2 →
- ∃∃T1,T2. ⦃G, L1⦄ ⊢ T ▶*[d, ∞] T1 & ⦃G, L2⦄ ⊢ T ▶*[d, ∞] T2 &
- ⦃G, L1⦄ ⊢ T1 ➡*[h, g] T2 & (T1 = T2 → ⊥).
-#h #g #G #L1 #L2 #T #d #H elim H -L1 -L2 -T -d
-[ #I1 #I2 #L1 #L2 #K1 #K2 #V1 #V2 #d #i #Hdi #HLK1 #HLK2 #_ #HnV12 #HL12
- elim (lpxs_ldrop_conf … HLK1 … HL12) -HL12 #Y #H #HY
- elim (lpxs_inv_pair1 … H) -H #Z #X #_ #HV12 #H destruct
- lapply (ldrop_mono … HY … HLK2) -HY #H destruct
- lapply (ldrop_fwd_drop2 … HLK1) #H2LK1
- elim (lift_total V1 0 (i+1)) #T1 #HVT1
- elim (lift_total V2 0 (i+1)) #T2 #HVT2
- @(ex4_2_intro … T1 T2) /3 width=10 by cpxs_lift, cpys_subst, lift_inj/ (**) (* explicit constructor *)
-| #I1 #I2 #L1 #L2 #K1 #K2 #V #d #i #Hdi #HLK1 #HLK2 #_ #IHK12 #HL12
- elim (lpxs_ldrop_conf … HLK1 … HL12) -HL12 #Y #H #HY
- elim (lpxs_inv_pair1 … H) -H #Z #X #HK12 #_ #H destruct
- lapply (ldrop_mono … HY … HLK2) -HY #H destruct
- elim (IHK12 HK12) -IHK12 -HK12 #V1 #V2 #HV1 #HV2 #HV12 #HnV12
- lapply (ldrop_fwd_drop2 … HLK1) #H2LK1
- elim (lift_total V1 0 (i+1)) #T1 #HVT1
- elim (lift_total V2 0 (i+1)) #T2 #HVT2
- @(ex4_2_intro … T1 T2) /3 width=10 by cpxs_lift, cpys_subst_Y2, lift_inj/ (**) (* explicit constructor *)
-| #a #I #L1 #L2 #V #T #d #_ #IHV #HL12 elim (IHV HL12) -IHV -HL12
- #V1 #V2 #HV1 #HV2 #HV12 #HnV12
- @(ex4_2_intro … (ⓑ{a,I}V1.T) (ⓑ{a,I}V2.T)) /2 width=1 by cpys_bind, cpxs_pair_sn/
- #H destruct /2 width=1 by/
-| #a #I #L1 #L2 #V #T #d #_ #IHT #HL12 elim (IHT ?) /2 width=1 by lpxs_pair_refl/ -IHT -HL12
- #T1 #T2 #HT1 #HT2 #HT12 #HnT12
- @(ex4_2_intro … (ⓑ{a,I}V.T1) (ⓑ{a,I}V.T2)) /2 width=1 by cpys_bind, cpxs_bind_dx/
- #H destruct /2 width=1 by/
-| #I #L1 #L2 #V #T #d #_ #IHV #HL12 elim (IHV HL12) -IHV -HL12
- #V1 #V2 #HV1 #HV2 #HV12 #HnV12
- @(ex4_2_intro … (ⓕ{I}V1.T) (ⓕ{I}V2.T)) /2 width=1 by cpys_flat, cpxs_pair_sn/
- #H destruct /2 width=1 by/
-| #I #L1 #L2 #V #T #d #_ #IHT #HL12 elim (IHT HL12) -IHT -HL12
- #T1 #T2 #HT1 #HT2 #HT12 #HnT12
- @(ex4_2_intro … (ⓕ{I}V.T1) (ⓕ{I}V.T2)) /2 width=1 by cpys_flat, cpxs_flat_dx/
- #H destruct /2 width=1 by/
-]
-qed-.
-
-lemma lpxs_nlleq_fwd_cpxs: ∀h,g,G,L1,L2,T,d. ⦃G, L1⦄ ⊢ ➡*[h, g] L2 →
- (L1 ⋕[T, d] L2 → ⊥) →
- ∃∃T1,T2. ⦃G, L1⦄ ⊢ T ▶*[d, ∞] T1 & ⦃G, L2⦄ ⊢ T ▶*[d, ∞] T2 &
- ⦃G, L1⦄ ⊢ T1 ➡*[h, g] T2 & (T1 = T2 → ⊥).
-/5 width=4 by lpxs_llneq_fwd_cpxs, lpxs_fwd_length, llneq_llneqa, conj/ qed-.