It does not work recursively...

diff --git a/helm/software/matita/nlibrary/sets/sets.ma b/helm/software/matita/nlibrary/sets/sets.ma
index 96521773738786bc15cd6eb0d2bbc4c35ce8be50..c21751c2148d6b9679218b2ac34f7e90da071d52 100644 (file)
--- a/helm/software/matita/nlibrary/sets/sets.ma
+++ b/helm/software/matita/nlibrary/sets/sets.ma
@@ -187,7 +187,7 @@ interpretation "prop21 mem" 'prop2 l r = (prop21_mem ??????? l r).
     
 nlemma test: ∀U.∀A,B:qpowerclass U. A ∩ B = A →
  ∀x,y. x=y → x ∈ A → y ∈ A ∩ B.
- #U; #A; #B; #H; #x; #y; #K; #K2; napply (. K^-1‡H); nassumption;
+ #U; #A; #B; #H; #x; #y; #K; #K2; napply (. K^-1‡(H^-1‡#)); nassumption;
 nqed. 
 
 (*