(* *)
(**************************************************************************)
+include "ground_2/relocation/rtmap_basic.ma".
include "basic_2/relocation/lifts.ma".
include "apps_2/models/veq.ma".
(* EVALUATION EQUIVALENCE **************************************************)
-lemma pippo (M) (gv): is_model M → is_extensional M →
- ∀f,T1,T2. ⬆*[f] T1 ≘ T2 → ∀n. ⫯*[n] 𝐔❴1❵ = f →
- ∀lv,d. ⟦T1⟧[gv, lv] ≗{M} ⟦T2⟧[gv, ⫯[n←d]lv].
+(* Forward lemmas with generic relocation ***********************************)
+
+fact lifts_fwd_vlift_aux (M) (gv): is_model M → is_extensional M →
+ ∀f,T1,T2. ⬆*[f] T1 ≘ T2 → ∀m. 𝐁❴m,1❵ = f →
+ ∀lv,d. ⟦T1⟧[gv, lv] ≗{M} ⟦T2⟧[gv, ⫯[m←d]lv].
#M #gv #H1M #H2M #f #T1 #T2 #H elim H -f -T1 -T2
[ /4 width=3 by seq_trans, seq_sym, ms/
-| #f #i1 #i2 #Hi12 #n #Hn #lv #d
+| #f #i1 #i2 #Hi12 #m #Hm #lv #d destruct
@(mr … H1M) [4,5: @(seq_sym … H1M) @(ml … H1M) |1,2: skip ]
+ elim (lt_or_ge i1 m) #Hi1
+ [ lapply (at_basic_inv_lt … Hi12) -Hi12 // #H destruct
+ >vlift_lt /2 width=1 by mq/
+ | lapply (at_basic_inv_ge … Hi12) -Hi12 // #H destruct
+ >vlift_gt /2 width=1 by mq, le_S_S/
+ ]
| /4 width=3 by seq_trans, seq_sym, mg/
-| #f #p * #V1 #V2 #T1 #T2 #_ #_ #IHV #IHT #n #Hn #lv #d
+| #f #p * #V1 #V2 #T1 #T2 #_ #_ #IHV #IHT #m #Hm #lv #d destruct
[ @(mr … H1M) [4,5: @(seq_sym … H1M) @(md … H1M) |1,2: skip ]
@(seq_trans … H1M)
[2: @(ti_comp_l … H1M) | skip ]
[2: @(vlift_comp … lv lv) | skip ]
[3: /2 width=1 by veq_refl/ ]
[2: @(IHV … d) // | skip ]
- @(seq_trans … H1M) [2: @(IHT … d) // | skip ]
+ @(seq_trans … H1M) [2: @(IHT (↑m) … d) // | skip ]
/4 width=1 by seq_sym, ti_ext_l, vlift_swap/
| @mx /2 width=1 by/ #d0 @(seq_trans … H1M)
[3: @(seq_sym … H1M) @(ti_ext_l … H1M) | skip ]
[2: @vlift_swap // | skip ]
/2 width=1 by/
]
-| #f * #V1 #v2 #T1 #T2 #_ #_ #IHV #IHT #n #Hn #lv #d
+| #f * #V1 #v2 #T1 #T2 #_ #_ #IHV #IHT #m #Hm #lv #d
[ /4 width=5 by seq_sym, ma, mc, mr/
| /4 width=5 by seq_sym, me, mr/
]
-]
+]
+qed-.
+
+lemma lifts_SO_fwd_vlift (M) (gv): is_model M → is_extensional M →
+ ∀T1,T2. ⬆*[1] T1 ≘ T2 →
+ ∀lv,d. ⟦T1⟧[gv, lv] ≗{M} ⟦T2⟧[gv, ⫯[d]lv].
+/2 width=3 by lifts_fwd_vlift_aux/ qed-.