include "delayed_updating/substitution/lift_eq.ma".
include "delayed_updating/syntax/path_structure.ma".
include "delayed_updating/syntax/path_proper.ma".
+include "ground/xoa/ex_4_2.ma".
+include "ground/xoa/ex_3_2.ma".
(* LIFT FOR PATH ***********************************************************)
#p @(path_ind_lift … p) -p //
qed.
-(* Properties with proper condition for path ********************************)
+(* Destructions with structure **********************************************)
+
+lemma lift_des_structure (q) (p) (f):
+ ⊗q = ↑[f]p → ⊗q = ⊗p.
+// qed-.
+
+(* Constructions with proper condition for path *****************************)
lemma lift_append_proper_dx (p2) (p1) (f): Ꝕp2 →
(⊗p1)●(↑[↑[p1]f]p2) = ↑[f](p1●p2).
lemma lift_d_empty_dx (n) (p) (f):
(⊗p)◖𝗱((↑[p]f)@❨n❩) = ↑[f](p◖𝗱n).
-/3 width=3 by ppc_lcons, lift_append_proper_dx/
+#n #p #f <lift_append_proper_dx //
qed.
lemma lift_L_dx (p) (f):
(⊗p)◖𝗟 = ↑[f](p◖𝗟).
-/3 width=3 by ppc_lcons, lift_append_proper_dx/
+#p #f <lift_append_proper_dx //
qed.
lemma lift_A_dx (p) (f):
(⊗p)◖𝗔 = ↑[f](p◖𝗔).
-/3 width=3 by ppc_lcons, lift_append_proper_dx/
+#p #f <lift_append_proper_dx //
qed.
lemma lift_S_dx (p) (f):
(⊗p)◖𝗦 = ↑[f](p◖𝗦).
-/3 width=3 by ppc_lcons, lift_append_proper_dx/
+#p #f <lift_append_proper_dx //
qed.
+
+(* Advanced inversions with proj_path ***************************************)
+
+lemma lift_path_inv_d_sn (k) (q) (p) (f):
+ (𝗱k◗q) = ↑[f]p →
+ ∃∃r,h. 𝐞 = ⊗r & (↑[r]f)@❨h❩ = k & 𝐞 = q & r◖𝗱h = p.
+#k #q #p @(path_ind_lift … p) -p
+[| #n | #n #l #p |*: #p ] [|*: #IH ] #f
+[ <lift_path_empty #H destruct
+| <lift_path_d_empty_sn #H destruct -IH
+ /2 width=5 by ex4_2_intro/
+| <lift_path_d_lcons_sn #H
+ elim (IH … H) -IH -H #r #h #Hr #Hh #Hq #Hp destruct
+ /2 width=5 by ex4_2_intro/
+| <lift_path_L_sn #H destruct
+| <lift_path_A_sn #H destruct
+| <lift_path_S_sn #H destruct
+]
+qed-.
+
+lemma lift_path_inv_L_sn (q) (p) (f):
+ (𝗟◗q) = ↑[f]p →
+ ∃∃r1,r2. 𝐞 = ⊗r1 & q = ↑[⫯↑[r1]f]r2 & r1●𝗟◗r2 = p.
+#q #p @(path_ind_lift … p) -p
+[| #n | #n #l #p |*: #p ] [|*: #IH ] #f
+[ <lift_path_empty #H destruct
+| <lift_path_d_empty_sn #H destruct
+| <lift_path_d_lcons_sn #H
+ elim (IH … H) -IH -H #r1 #r2 #Hr1 #Hq #Hp destruct
+ /2 width=5 by ex3_2_intro/
+| <lift_path_L_sn #H destruct -IH
+ /2 width=5 by ex3_2_intro/
+| <lift_path_A_sn #H destruct
+| <lift_path_S_sn #H destruct
+]
+qed-.
+
+lemma lift_path_inv_A_sn (q) (p) (f):
+ (𝗔◗q) = ↑[f]p →
+ ∃∃r1,r2. 𝐞 = ⊗r1 & q = ↑[↑[r1]f]r2 & r1●𝗔◗r2 = p.
+#q #p @(path_ind_lift … p) -p
+[| #n | #n #l #p |*: #p ] [|*: #IH ] #f
+[ <lift_path_empty #H destruct
+| <lift_path_d_empty_sn #H destruct
+| <lift_path_d_lcons_sn #H
+ elim (IH … H) -IH -H #r1 #r2 #Hr1 #Hq #Hp destruct
+ /2 width=5 by ex3_2_intro/
+| <lift_path_L_sn #H destruct
+| <lift_path_A_sn #H destruct -IH
+ /2 width=5 by ex3_2_intro/
+| <lift_path_S_sn #H destruct
+]
+qed-.
+
+lemma lift_path_inv_S_sn (q) (p) (f):
+ (𝗦◗q) = ↑[f]p →
+ ∃∃r1,r2. 𝐞 = ⊗r1 & q = ↑[↑[r1]f]r2 & r1●𝗦◗r2 = p.
+#q #p @(path_ind_lift … p) -p
+[| #n | #n #l #p |*: #p ] [|*: #IH ] #f
+[ <lift_path_empty #H destruct
+| <lift_path_d_empty_sn #H destruct
+| <lift_path_d_lcons_sn #H
+ elim (IH … H) -IH -H #r1 #r2 #Hr1 #Hq #Hp destruct
+ /2 width=5 by ex3_2_intro/
+| <lift_path_L_sn #H destruct
+| <lift_path_A_sn #H destruct
+| <lift_path_S_sn #H destruct -IH
+ /2 width=5 by ex3_2_intro/
+]
+qed-.
+
+(* Inversions with proper condition for path ********************************)
+
+lemma lift_inv_append_proper_dx (q2) (q1) (p) (f): Ꝕq2 →
+ q1●q2 = ↑[f]p →
+ ∃∃p1,p2. ⊗p1 = q1 & ↑[↑[p1]f]p2 = q2 & p1●p2 = p.
+#q2 #q1 elim q1 -q1
+[ #p #f #Hq2 <list_append_empty_sn #H destruct
+ /2 width=5 by ex3_2_intro/
+| * [ #n1 ] #q1 #IH #p #f #Hq2 <list_append_lcons_sn #H
+ [ elim (lift_path_inv_d_sn … H) -H #r1 #m1 #_ #_ #H0 #_ -IH
+ elim (eq_inv_list_empty_append … H0) -H0 #_ #H0 destruct
+ elim Hq2 -Hq2 //
+ | elim (lift_path_inv_L_sn … H) -H #r1 #s1 #Hr1 #Hs1 #H0 destruct
+ elim (IH … Hs1) -IH -Hs1 // -Hq2 #p1 #p2 #H1 #H2 #H3 destruct
+ @(ex3_2_intro … (r1●𝗟◗p1)) //
+ <structure_append <Hr1 -Hr1 //
+ | elim (lift_path_inv_A_sn … H) -H #r1 #s1 #Hr1 #Hs1 #H0 destruct
+ elim (IH … Hs1) -IH -Hs1 // -Hq2 #p1 #p2 #H1 #H2 #H3 destruct
+ @(ex3_2_intro … (r1●𝗔◗p1)) //
+ <structure_append <Hr1 -Hr1 //
+ | elim (lift_path_inv_S_sn … H) -H #r1 #s1 #Hr1 #Hs1 #H0 destruct
+ elim (IH … Hs1) -IH -Hs1 // -Hq2 #p1 #p2 #H1 #H2 #H3 destruct
+ @(ex3_2_intro … (r1●𝗦◗p1)) //
+ <structure_append <Hr1 -Hr1 //
+ ]
+]
+qed-.