O-Basic Topologies do form a category.

diff --git a/helm/software/matita/contribs/formal_topology/overlap/o-basic_topologies.ma b/helm/software/matita/contribs/formal_topology/overlap/o-basic_topologies.ma
index a2ed2fee0203724c2a215571059b2a0e8d641876..c0fb6c6a7ff64f158bb667149ca1530ec497d69f 100644 (file)
--- a/helm/software/matita/contribs/formal_topology/overlap/o-basic_topologies.ma
+++ b/helm/software/matita/contribs/formal_topology/overlap/o-basic_topologies.ma
@@ -157,11 +157,10 @@ definition BTop: category1.
     apply rule (#‡ASSOC1\sup -1);
   | intros; simplify;
     change with ((a⎻* ∘ (id1 ? o1)⎻* ) ∘ A o1 = a⎻* ∘ A o1);
-    apply rule (†((id_neutral_right1 ????)‡#));
-    apply refl1*)
-  | intros; simplify; intro; simplify;
-    apply (.= †((id_neutral_left1 ????)‡#));
-    apply refl1]
+    apply (#‡(id_neutral_right1 : ?));
+  | intros; simplify;
+    change with (((id1 ? o2)⎻* ∘ a⎻* ) ∘ A o1 = a⎻* ∘ A o1);
+    apply (#‡(id_neutral_left1 : ?));]
 qed.
 
 (*