X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Frt_computation%2Fcprs.ma;h=ff8271ebda2a482c36b7ed9734a64c6444c9bf3d;hb=31be09cc0d040577917783e050e1d38c0daa8f01;hp=230160ac73a7dda9a0ac4867acd43e02b0e3d882;hpb=5c186c72f508da0849058afeecc6877cd9ed6303;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/rt_computation/cprs.ma b/matita/matita/contribs/lambdadelta/basic_2/rt_computation/cprs.ma
index 230160ac7..ff8271ebd 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/rt_computation/cprs.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/rt_computation/cprs.ma
@@ -84,15 +84,13 @@ lemma cprs_inv_sort1 (h) (G) (L): ∀X2,s. ⦃G, L⦄ ⊢ ⋆s ➡*[h] X2 → X2
 
 (* Basic_1: was: pr3_gen_cast *)
 lemma cprs_inv_cast1 (h) (G) (L): ∀W1,T1,X2. ⦃G, L⦄ ⊢ ⓝW1.T1 ➡*[h] X2 →
-                                  ∨∨ ⦃G, L⦄ ⊢ T1 ➡*[h] X2
-                                   | ∃∃W2,T2. ⦃G, L⦄ ⊢ W1 ➡*[h] W2 & ⦃G, L⦄ ⊢ T1 ➡*[h] T2 & X2 = ⓝW2.T2.
-#h #G #L #W1 #T1 #X2 #H @(cprs_ind_dx … H) -X2
-[ /3 width=5 by ex3_2_intro, or_intror/
-| #X #X2 #_ #HX2 * /3 width=3 by cprs_step_dx, or_introl/ *
-  #W #T #HW1 #HT1 #H destruct
-  elim (cpr_inv_cast1 … HX2) -HX2 /3 width=3 by cprs_step_dx, or_introl/ *
-  #W2 #T2 #HW2 #HT2 #H destruct
-  /4 width=5 by cprs_step_dx, ex3_2_intro, or_intror/
+                                  ∨∨ ∃∃W2,T2. ⦃G, L⦄ ⊢ W1 ➡*[h] W2 & ⦃G, L⦄ ⊢ T1 ➡*[h] T2 & X2 = ⓝW2.T2
+                                   | ⦃G, L⦄ ⊢ T1 ➡*[h] X2.
+#h #G #L #W1 #T1 #X2 #H
+elim (cpms_inv_cast1 … H) -H
+[ /2 width=1 by or_introl/
+| /2 width=1 by or_intror/
+| * #m #_ #H destruct
 ]
 qed-.