X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Funwind%2Fsstas.ma;h=93fe0a7e0ee89f20f9f6b86fbe1f21c0fea93e7d;hb=0dec595530e6da8ca16af84e40b59c998e6ed4af;hp=c504e4edc1dfd5fbf99745a33b82ade43434e1ac;hpb=f897953a3fff70a0c1de4683c196385d563ce238;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/unwind/sstas.ma b/matita/matita/contribs/lambdadelta/basic_2/unwind/sstas.ma
index c504e4edc..93fe0a7e0 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/unwind/sstas.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/unwind/sstas.ma
@@ -47,8 +47,11 @@ qed-.
 
 (* Basic properties *********************************************************)
 
+lemma sstas_refl: ∀h,g,L. reflexive … (sstas h g L).
+// qed.
+
 lemma ssta_sstas: ∀h,g,L,T,U,l. ⦃h, L⦄ ⊢ T •[g, l+1] U → ⦃h, L⦄ ⊢ T •*[g] U.
-/3 width=2/ qed.
+/3 width=2 by R_to_star, ex_intro/ qed. (**) (* auto fails without trace *)
 
 lemma sstas_strap1: ∀h,g,L,T1,T2,U2,l. ⦃h, L⦄ ⊢ T1 •*[g] T2 → ⦃h, L⦄ ⊢ T2 •[g,l+1] U2 →
                     ⦃h, L⦄ ⊢ T1 •*[g] U2.