--- /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 "static_2/relocation/scl.ma".
+include "basic_2/rt_computation/rdsx_drops.ma".
+include "basic_2/rt_computation/rdsx_lpxs.ma".
+include "basic_2/rt_computation/sdsx.ma".
+
+axiom pippo (h) (f) (G) (V:term):
+ āL1. G ā¢ ā¬*[h,V] šā¦L1ā¦ ā
+ āL2. L1 āā§[f] L2 ā G ā¢ ā¬*[h,V] šā¦L2ā¦.
+
+
+(* STRONGLY NORMALIZING SELECTED LOCAL ENV.S FOR UNBOUND RT-TRANSITION ******)
+
+(* Properties with strongly normalizing referred local environments *********)
+
+(* Basic_2A1: uses: lsx_cpx_trans_lcosx *)
+lemma rdsx_cpx_trans_sdsx (h):
+ āG,L0,T1,T2. ā¦G,L0ā¦ ā¢ T1 ā¬[h] T2 ā
+ āf. G ā¢ ā¬*[h,f] šā¦L0ā¦ ā āL. L0 āā§[f] L ā
+ G ā¢ ā¬*[h,T1] šā¦Lā¦ ā G ā¢ ā¬*[h,T2] šā¦Lā¦.
+#h #G #L0 #T1 #T2 #H @(cpx_ind ā¦ H) -G -L0 -T1 -T2
+[ //
+| //
+| #I #G #K0 #V1 #V2 #W2 #_ #IH #HVW2 #g #H1 #Y #H2 #H3
+ elim (sdsx_inv_pair_gen ā¦ H1) -H1 *
+ [ #f #HK0 #H destruct
+ elim (scl_inv_push_sn ā¦ H2) -H2 #K #HK #H destruct
+ /4 width=8 by rdsx_lifts, rdsx_fwd_pair, drops_refl, drops_drop/
+ | #f #HV1 #HK0 #H destruct
+ elim (scl_inv_next_sn ā¦ H2) -H2 #K #HK #H destruct
+ /4 width=8 by pippo, rdsx_lifts, drops_refl, drops_drop/
+ ]
+| #I0 #G #K0 #T #U #i #_ #IH #HTU #g #H1 #Y #H2 #H3
+ lapply (sdsx_fwd_bind ā¦ H1) -H1 #HK0
+ elim (scl_fwd_bind_sn ā¦ H2) -H2 #I #K #HK #H destruct
+ /6 width=8 by rdsx_inv_lifts, rdsx_lifts, drops_refl, drops_drop/
+| #p #I #G #L0 #V1 #V2 #T1 #T2 #_ #_ #IHV12 #IHT12 #f #H1 #L #H2 #H3
+ elim (rdsx_inv_bind_void ā¦ H3) -H3 #HV1 #HT1
+ @rdsx_bind_void
+ [ /2 width=3 by/
+ | @(IHT12 (āf) ā¦ HT1)
+ [ @(sdsx_pair ā¦ H1)
+ | /2 width=1 by scl_next/
+
+ /4 width=2 by lsubsx_pair, rdsx_bind_void/
+| #I0 #G #L0 #V1 #V2 #T1 #T2 #_ #_ #IHV12 #IHT12 #f #L #HL0 #HL
+ elim (rdsx_inv_flat ā¦ HL) -HL /3 width=2 by rdsx_flat/
+| #G #L0 #V #U1 #T1 #T2 #HTU1 #_ #IHT12 #f #L #HL0 #HL
+ elim (rdsx_inv_bind ā¦ HL) -HL #HV #HU1
+ /5 width=8 by rdsx_inv_lifts, drops_refl, drops_drop/
+| #G #L0 #V #T1 #T2 #_ #IHT12 #f #L #HL0 #HL
+ elim (rdsx_inv_flat ā¦ HL) -HL /2 width=2 by/
+| #G #L0 #V1 #V2 #T #_ #IHV12 #f #L #HL0 #HL
+ elim (rdsx_inv_flat ā¦ HL) -HL /2 width=2 by/
+| #p #G #L0 #V1 #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #IHV12 #IHW12 #IHT12 #f #L #HL0 #HL
+ elim (rdsx_inv_flat ā¦ HL) -HL #HV1 #HL
+ elim (rdsx_inv_bind ā¦ HL) -HL #HW1 #HT1
+ /4 width=2 by lsubsx_pair, rdsx_bind_void, rdsx_flat/
+| #p #G #L0 #V1 #V2 #U2 #W1 #W2 #T1 #T2 #_ #_ #_ #IHV12 #IHW12 #IHT12 #HVU2 #f #L #HL0 #HL
+ elim (rdsx_inv_flat ā¦ HL) -HL #HV1 #HL
+ elim (rdsx_inv_bind ā¦ HL) -HL #HW1 #HT1
+ /6 width=8 by lsubsx_pair, rdsx_lifts, rdsx_bind_void, rdsx_flat, drops_refl, drops_drop/
+]
+qed-.
+
+(* Advanced properties of strongly normalizing referred local environments **)
+
+(* Basic_2A1: uses: lsx_cpx_trans_O *)
+lemma rdsx_cpx_trans (h):
+ āG,L,T1,T2. ā¦G,Lā¦ ā¢ T1 ā¬[h] T2 ā
+ G ā¢ ā¬*[h,T1] šā¦Lā¦ ā G ā¢ ā¬*[h,T2] šā¦Lā¦.
+/3 width=6 by rdsx_cpx_trans_lsubsx, lsubsx_refl/ qed-.
+
+lemma rdsx_cpxs_trans (h):
+ āG,L,T1,T2. ā¦G,Lā¦ ā¢ T1 ā¬*[h] T2 ā
+ G ā¢ ā¬*[h,T1] šā¦Lā¦ ā G ā¢ ā¬*[h,T2] šā¦Lā¦.
+#h #G #L #T1 #T2 #H
+@(cpxs_ind_dx ???????? H) -T1 //
+/3 width=3 by rdsx_cpx_trans/
+qed-.
+*)