advances on lfsx ...

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / static / lfxs.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/static/lfxs.ma b/matita/matita/contribs/lambdadelta/basic_2/static/lfxs.ma
index f754e46deaa6d0aa066ccf3ec6798f75df6bbc34..d7dae247e3ccbb1e041377d1936d505ae00c47e2 100644 (file)
--- a/matita/matita/contribs/lambdadelta/basic_2/static/lfxs.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/static/lfxs.ma
@@ -89,6 +89,14 @@ lemma lfxs_co: ∀R1,R2. (∀L,T1,T2. R1 L T1 T2 → R2 L T1 T2) →
 #R1 #R2 #HR #L1 #L2 #T * /4 width=7 by lexs_co, ex2_intro/
 qed-.
 
+lemma lfxs_isid: ∀R1,R2,L1,L2,T1,T2.
+                 (∀f. L1 ⊢ 𝐅*⦃T1⦄ ≡ f → 𝐈⦃f⦄) → 
+                 (∀f. 𝐈⦃f⦄ → L1 ⊢ 𝐅*⦃T2⦄ ≡ f) → 
+                 L1 ⦻*[R1, T1] L2 → L1 ⦻*[R2, T2] L2.
+#R1 #R2 #L1 #L2 #T1 #T2 #H1 #H2 *
+/4 width=7 by lexs_co_isid, ex2_intro/
+qed-.
+
 (* Basic inversion lemmas ***************************************************)
 
 lemma lfxs_inv_atom_sn: ∀R,Y2,T. ⋆ ⦻*[R, T] Y2 → Y2 = ⋆.
@@ -260,12 +268,13 @@ lemma lfxs_fwd_dx: ∀R,I,L1,K2,T,V2. L1 ⦻*[R, T] K2.ⓑ{I}V2 →
 /2 width=3 by ex1_2_intro/
 qed-.
 
-(* Basic_2A1: removed theorems 24:
+(* Basic_2A1: removed theorems 25:
               llpx_sn_sort llpx_sn_skip llpx_sn_lref llpx_sn_free llpx_sn_gref
               llpx_sn_bind llpx_sn_flat
               llpx_sn_inv_bind llpx_sn_inv_flat
               llpx_sn_fwd_lref llpx_sn_fwd_pair_sn llpx_sn_fwd_length
               llpx_sn_fwd_bind_sn llpx_sn_fwd_bind_dx llpx_sn_fwd_flat_sn llpx_sn_fwd_flat_dx
               llpx_sn_refl llpx_sn_Y llpx_sn_bind_O llpx_sn_ge_up llpx_sn_ge llpx_sn_co
-              llpx_sn_fwd_drop_sn llpx_sn_fwd_drop_dx              
+              llpx_sn_fwd_drop_sn llpx_sn_fwd_drop_dx
+              llpx_sn_dec      
 *)