X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fcontribs%2Fformal_topology%2Foverlap%2Fsubsets.ma;h=4152f48529a54ea91d8ef461b6dcfd8b45144169;hb=8df31f2c696c408e888fb8b94478799b04771f15;hp=e6d1872166143e9f891ee27e89305a8cc0d5c658;hpb=cb98bd7054893edee16aadd6741ec5210b04afbc;p=helm.git

diff --git a/helm/software/matita/contribs/formal_topology/overlap/subsets.ma b/helm/software/matita/contribs/formal_topology/overlap/subsets.ma
index e6d187216..4152f4852 100644
--- a/helm/software/matita/contribs/formal_topology/overlap/subsets.ma
+++ b/helm/software/matita/contribs/formal_topology/overlap/subsets.ma
@@ -129,7 +129,7 @@ interpretation "union" 'union U V = (fun21 ___ (union _) U V).
 (* qua non riesco a mettere set *)
 definition singleton: ∀A:setoid. unary_morphism1 A (Ω \sup A).
  intros; constructor 1;
-  [ apply (λa:A.{b | eq ? a b}); unfold setoid1_of_setoid; simplify;
+  [ apply (λa:A.{b | a =_0 b}); unfold setoid1_of_setoid; simplify;
     intros; simplify;
     split; intro;
     apply (.= e1);