long awaited update in basic_2

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / rt_computation / lfpxs_fqup.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/rt_computation/lfpxs_fqup.ma b/matita/matita/contribs/lambdadelta/basic_2/rt_computation/lfpxs_fqup.ma
index 52159d8cdac9f5495c937dac2c4e695ca2bc07da..6c7615ce4dec2c6060555a7e6ee79182017d8c34 100644 (file)
--- a/matita/matita/contribs/lambdadelta/basic_2/rt_computation/lfpxs_fqup.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/rt_computation/lfpxs_fqup.ma
@@ -19,7 +19,6 @@ include "basic_2/rt_computation/lfpxs.ma".
 
 (* Advanced properties ******************************************************)
 
-(* Basic_2A1: uses: lpxs_refl *)
 lemma lfpxs_refl: ∀h,G,T. reflexive … (lfpxs h G T).
 /2 width=1 by tc_lfxs_refl/ qed.
 
@@ -29,6 +28,10 @@ lemma lfpxs_fwd_bind_dx: ∀h,p,I,G,L1,L2,V,T. ⦃G, L1⦄ ⊢ ⬈*[h, ⓑ{p,I}V
                          ⦃G, L1.ⓑ{I}V⦄ ⊢ ⬈*[h, T] L2.ⓑ{I}V.
 /2 width=2 by tc_lfxs_fwd_bind_dx/ qed-.
 
+lemma lfpxs_fwd_bind_dx_void: ∀h,p,I,G,L1,L2,V,T. ⦃G, L1⦄ ⊢ ⬈*[h, ⓑ{p,I}V.T] L2 →
+                              ⦃G, L1.ⓧ⦄ ⊢ ⬈*[h, T] L2.ⓧ.
+/2 width=4 by tc_lfxs_fwd_bind_dx_void/ qed-.
+
 (* Advanced eliminators *****************************************************)
 
 (* Basic_2A1: uses: lpxs_ind *)