- nDestructTac: Sys.break handled in two places

[helm.git] / matita / matita / contribs / lambda_delta / basic_2 / computation / cprs_tstc_vector.ma

diff --git a/matita/matita/contribs/lambda_delta/basic_2/computation/cprs_tstc_vector.ma b/matita/matita/contribs/lambda_delta/basic_2/computation/cprs_tstc_vector.ma
index d12a9f498811ef033f202c59c46dd3460a946aae..a7f9b33cdaf39d761e0dd0c8e32818b8421f7c0d 100644 (file)
--- a/matita/matita/contribs/lambda_delta/basic_2/computation/cprs_tstc_vector.ma
+++ b/matita/matita/contribs/lambda_delta/basic_2/computation/cprs_tstc_vector.ma
@@ -20,6 +20,21 @@ include "basic_2/computation/cprs_tstc.ma".
 
 (* Vector form of forward lemmas involving same top term constructor ********)
 
+(* Basic_1: was just: nf2_iso_appls_lref *)
+lemma cprs_fwd_cnf_vector: ∀L,T.  𝐒⦃T⦄ → L ⊢ 𝐍⦃T⦄ → ∀Vs,U. L ⊢ ⒶVs.T ➡* U → ⒶVs.T ≃ U.
+#L #T #H1T #H2T #Vs elim Vs -Vs [ @(cprs_fwd_cnf … H2T) ] (**) (* /2 width=3 by cprs_fwd_cnf/ does not work *)
+#V #Vs #IHVs #U #H
+elim (cprs_inv_appl1 … H) -H *
+[ -IHVs #V0 #T0 #_ #_ #H destruct /2 width=1/
+| #V0 #W0 #T0 #HV0 #HT0 #HU
+  lapply (IHVs … HT0) -IHVs -HT0 #HT0
+  elim (tstc_inv_bind_appls_simple … HT0 ?) //
+| #V1 #V2 #V0 #T0 #HV1 #HV12 #HT0 #HU
+  lapply (IHVs … HT0) -IHVs -HT0 #HT0
+  elim (tstc_inv_bind_appls_simple … HT0 ?) //
+]
+qed-.
+
 (* Basic_1: was: pr3_iso_appls_beta *)
 lemma cprs_fwd_beta_vector: ∀L,Vs,V,W,T,U. L ⊢ ⒶVs. ⓐV. ⓛW. T ➡* U →
                             ⒶVs. ⓐV. ⓛW. T ≃ U ∨ L ⊢ ⒶVs. ⓓV. T ➡* U.