- the PARTIAL COMMIT continues, we issue the "reduction" component

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / reduction / cpr.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/reduction/cpr.ma b/matita/matita/contribs/lambdadelta/basic_2/reduction/cpr.ma
index 6db05fe53788180bc2a416e25cc1b2b1979a963d..d2034f9d196d5f2e421b86d31102095990f4b0bb 100644 (file)
--- a/matita/matita/contribs/lambdadelta/basic_2/reduction/cpr.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/reduction/cpr.ma
@@ -15,6 +15,7 @@
 include "basic_2/notation/relations/pred_4.ma".
 include "basic_2/grammar/genv.ma".
 include "basic_2/static/lsubr.ma".
+include "basic_2/unfold/lstas.ma".
 
 (* CONTEXT-SENSITIVE PARALLEL REDUCTION FOR TERMS ***************************)
 
@@ -93,6 +94,20 @@ lemma cpr_delift: ∀G,K,V,T1,L,d. ⇩[d] L ≡ (K.ⓓV) →
 ]
 qed-.
 
+fact lstas_cpr_aux: ∀h,G,L,T1,T2,l. ⦃G, L⦄ ⊢ T1 •*[h, l] T2 →
+                    l = 0 → ⦃G, L⦄ ⊢ T1 ➡ T2.
+#h #G #L #T1 #T2 #l #H elim H -G -L -T1 -T2 -l
+/3 width=1 by cpr_eps, cpr_flat, cpr_bind/
+[ #G #L #l #k #H0 destruct normalize //
+| #G #L #K #V1 #V2 #W2 #i #l #HLK #_ #HVW2 #IHV12 #H destruct
+  /3 width=6 by cpr_delta/
+| #G #L #K #V1 #V2 #W2 #i #l #_ #_ #_ #_ <plus_n_Sm #H destruct
+]
+qed-.
+
+lemma lstas_cpr: ∀h,G,L,T1,T2. ⦃G, L⦄ ⊢ T1 •*[h, 0] T2 → ⦃G, L⦄ ⊢ T1 ➡ T2.
+/2 width=4 by lstas_cpr_aux/ qed.
+
 (* Basic inversion lemmas ***************************************************)
 
 fact cpr_inv_atom1_aux: ∀G,L,T1,T2. ⦃G, L⦄ ⊢ T1 ➡ T2 → ∀I. T1 = ⓪{I} →