X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fmatita%2Flibrary%2Fnat%2Fplus.ma;h=d595dad19113cb6626ec4e58cc1e8a2d389be2b1;hb=4167cea65ca58897d1a3dbb81ff95de5074700cc;hp=79640b1362f86e9a654cc55a568d766daa8e0120;hpb=ab44166935d77276c04fcce50aa8281292776e29;p=helm.git

diff --git a/helm/matita/library/nat/plus.ma b/helm/matita/library/nat/plus.ma
index 79640b136..d595dad19 100644
--- a/helm/matita/library/nat/plus.ma
+++ b/helm/matita/library/nat/plus.ma
@@ -43,7 +43,7 @@ simplify.rewrite > H.apply plus_n_Sm.
 qed.
 
 theorem associative_plus : associative nat plus.
-simplify.intros.elim x.
+unfold associative.intros.elim x.
 simplify.reflexivity.
 simplify.apply eq_f.assumption.
 qed.
@@ -62,9 +62,9 @@ theorem inj_plus_r: \forall p,n,m:nat. p+n = p+m \to n=m
 
 theorem injective_plus_l: \forall m:nat.injective nat nat (\lambda n.n+m).
 intro.simplify.intros.
-apply injective_plus_r m.
+apply (injective_plus_r m).
 rewrite < sym_plus.
-rewrite < sym_plus y.
+rewrite < (sym_plus y).
 assumption.
 qed.