(* *)
(**************************************************************************)
+(* include "basic_2/syntax/lveq_length.ma". *)
include "basic_2/static/fle.ma".
include "basic_2/static/lfxs_lfxs.ma".
(* GENERIC EXTENSION ON REFERRED ENTRIES OF A CONTEXT-SENSITIVE REALTION ****)
-
+(*
+lemma pippo: ∀L1,L2,n1,n2. L1 ≋ⓧ*[n1, n2] L2 →
+ ∀T,f. L1 ⊢ 𝐅*⦃T⦄ ≡ f → ∃g. ↑*[n1]g = f.
+*)
(* Properties with free variables inclusion for restricted closures *********)
-
+(*
lemma fle_lfxs_trans: ∀R,L1,T1,T2. ⦃L1, T1⦄ ⊆ ⦃L1, T2⦄ →
∀L2. L1 ⪤*[R, T2] L2 → L1 ⪤*[R, T1] L2.
-#R #L1 #T1 #T2 * #f1 #f2 #Hf1 #Hf2 #Hf12 #L2 #HL12
+#R #L1 #T1 #T2 * #x #n #f1 #f2 #Hf1 #Hf2 #Hn #Hf #L2 #HL12
+lapply (lveq_inj_length … Hn ?) // #H destruct
+
+
+ Hn : (L1≋ⓧ*[n,n]L1) (L1⊢𝐅*⦃T1⦄≡f1) →
+
+lapply (lfxs_inv_frees … HL12 … Hf2) -HL12 -Hf2 #HL12
+@(ex2_intro … Hf1) -Hf1
+@(sle_lexs_trans … HL12) -HL12 //
+
/4 width=5 by lfxs_inv_frees, sle_lexs_trans, ex2_intro/
qed-.
+*)
\ No newline at end of file