- parallel substitution reaxiomatized

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / computation / fprs_cprs.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/computation/fprs_cprs.ma b/matita/matita/contribs/lambdadelta/basic_2/computation/fprs_cprs.ma
index ef2915ceaccec734d46552a67ed8cd7de190ec9f..9d4d954b8d25f16ab604a9f89b556a3f0fa289b8 100644 (file)
--- a/matita/matita/contribs/lambdadelta/basic_2/computation/fprs_cprs.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/computation/fprs_cprs.ma
@@ -21,6 +21,13 @@ include "basic_2/computation/lfprs_fprs.ma".
 
 (* Advanced properties ******************************************************)
 
+lemma fprs_flat_dx_tpr: ∀L1,L2,T1,T2. ⦃L1, T1⦄ ➡* ⦃L2, T2⦄ → ∀V1,V2. V1 ➡ V2 →
+                        ∀I. ⦃L1, ⓕ{I}V1.T1⦄ ➡* ⦃L2, ⓕ{I}V2.T2⦄.
+#L1 #L2 #T1 #T2 #HT12 @(fprs_ind … HT12) -L2 -T2 /3 width=1/
+#L #L2 #T #T2 #_ #HT2 #IHT2 #V1 #V2 #HV12 #I
+lapply (IHT2 … HV12 I) -IHT2 -HV12 /3 width=6/
+qed.
+
 lemma fprs_bind2_minus: ∀I,L1,L2,V1,T1,U2. ⦃L1, -ⓑ{I}V1.T1⦄ ➡* ⦃L2, U2⦄ →
                         ∃∃V2,T2. ⦃L1.ⓑ{I}V1, T1⦄ ➡* ⦃L2.ⓑ{I}V2, T2⦄ &
                                  U2 = -ⓑ{I}V2.T2.
@@ -41,7 +48,7 @@ lemma fprs_lift: ∀K1,K2,T1,T2. ⦃K1, T1⦄ ➡* ⦃K2, T2⦄ →
   elim (IHT1 … HLK1 … HTU1 HTU) -K1 -T1 #L #HU1 #HKL
   elim (fpr_lift … HT2 … HKL … HTU HTU2) -K -T -T2 /3 width=4/
 ]
-qed-.  
+qed-.
 
 (* Advanced inversion lemmas ************************************************)