some minor fixes

[helm.git] / helm / software / matita / library / logic / cprop_connectives.ma

diff --git a/helm/software/matita/library/logic/cprop_connectives.ma b/helm/software/matita/library/logic/cprop_connectives.ma
index c0bbdda18f3212715b49e5c8412cb7523c81e2ce..facda284891ed948ba1ed1e650e69c405fdd6b84 100644 (file)
--- a/helm/software/matita/library/logic/cprop_connectives.ma
+++ b/helm/software/matita/library/logic/cprop_connectives.ma
@@ -62,9 +62,17 @@ record Iff (A,B:CProp) : CProp ≝
  { if: A → B;
    fi: B → A
  }.
-
+ 
+record Iff1 (A,B:CProp) : CProp ≝
+ { if1: A → B;
+   fi1: B → A
+ }.
+ 
 interpretation "logical iff" 'iff x y = (Iff x y).
 
+notation "hvbox(a break ⇔ b)" right associative with precedence 25 for @{'iff1 $a $b}.
+interpretation "logical iff type1" 'iff1 x y = (Iff1 x y).
+
 inductive exT (A:Type) (P:A→CProp) : CProp ≝
   ex_introT: ∀w:A. P w → exT A P.