X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=Data%2FIntMap.hs;h=1be0bbeac8e78e74d274d68d30409e19662f1244;hb=641f8d5964b2b02f4cd7b9081adf6596c6f4d4d7;hp=e210442707c8bc98951e6f02e4bbf77f9ec8ea43;hpb=2701ac4127cbc37e6d1069e2f5240a1e0ec1e479;p=ghc-base.git

diff --git a/Data/IntMap.hs b/Data/IntMap.hs
index e210442..1be0bbe 100644
--- a/Data/IntMap.hs
+++ b/Data/IntMap.hs
@@ -138,6 +138,7 @@ import Data.Int
 import qualified Data.IntSet as IntSet
 import Data.Monoid (Monoid(..))
 import Data.Typeable
+import Data.Foldable (Foldable(foldMap))
 
 {-
 -- just for testing
@@ -216,6 +217,11 @@ instance Ord a => Monoid (IntMap a) where
     mappend = union
     mconcat = unions
 
+instance Foldable IntMap where
+    foldMap f Nil = mempty
+    foldMap f (Tip _k v) = f v
+    foldMap f (Bin _ _ l r) = foldMap f l `mappend` foldMap f r
+
 #if __GLASGOW_HASKELL__
 
 {--------------------------------------------------------------------