Bulat Ziganshin schrieb:
Hello Neil,
Tuesday, March 13, 2007, 12:38:14 PM, you wrote:
Are we going to have dependency problems by making Data.List depend on Data.Set? My guess is yes, but I'm not sure.
this is only an *implementation* dependency and it's ok as long as base includes both modules. if sometime in future situation will change, we can change implementation without boring users
In fact, as an implementation of sortNub/sortNubBy (if that is what we want) I would rather suggest to generalize the merge function (i.e. as below) for the mergesort algorithm (and possibly export merge, too). Cheers Christian merge :: (a -> a -> Ordering) -> (a -> a -> [a] -> [a]) -> [a] -> [a] -> [a] merge cmp jn l1 l2 = case l1 of [] -> l2 x1 : r1 -> case l2 of [] -> l1 x2 : r2 -> let recmerge = merge cmp jn in case cmp x1 x2 of LT -> x1 : recmerge r1 l2 EQ -> jn x1 x2 $ recmerge r1 r2 GT -> x2 : recmerge l1 r2