On Fri, Aug 20, 2010 at 11:13 AM, Roman Leshchinskiy
On 19/08/2010, at 19:38, Johan Tibell wrote:
Hi all,
I tried doing the "standard" worker/wrapper transform to some functions in Data.Map. For example, by transforming
insertWith' :: Ord k => (a -> a -> a) -> k -> a -> Map k a -> Map k a insertWith' f k x m = insertWithKey' (\_ x' y' -> f x' y') k x m
-- | Same as 'insertWithKey', but the combining function is applied strictly. insertWithKey' :: Ord k => (k -> a -> a -> a) -> k -> a -> Map k a -> Map k a insertWithKey' f kx x t0 = case t of Tip -> singleton kx $! x Bin sy ky y l r -> case compare kx ky of LT -> balance ky y (insertWithKey' f kx x l) r GT -> balance ky y l (insertWithKey' f kx x r) EQ -> let x' = f kx x y in seq x' (Bin sy kx x' l r)
Out of curiosity, is balance strict in the third argument? If not, does it make a difference if you make it strict?
I haven't checked since Milan completely rewrote balance but hasn't integrated his changes yet. I'll have a look at balance once those changes are in. -- Johan