On Wed, Nov 4, 2009 at 11:57 AM, Louis Wasserman
According to my documentation, the type of intersectionWith is (f :: a -> b -> c).
apologies, i'm using 6.10 so apparently my containers library is out of date. i guess this is another reason to upgrade to 6.12: http://www.haskell.org/ghc/dist/current/docs/html/users_guide/release-6-12-1... 1.5.9.5. containers Version number 0.3.0.0 (was 0.2.0.1) mapAccumRWithKey has been added to Data.IntMap. A Traversable instance has been added to Data.IntMap.IntMap. The types of Data.IntMap.intersectionWith and Data.IntMap.intersectionWithKey have been changed from intersectionWith :: (a -> b -> a) -> IntMap a -> IntMap b -> IntMap a intersectionWithKey :: (Key -> a -> b -> a) -> IntMap a -> IntMap b -> IntMap a to intersectionWith :: (a -> b -> c) -> IntMap a -> IntMap b -> IntMap c intersectionWithKey :: (Key -> a -> b -> c) -> IntMap a -> IntMap b -> IntMap c b