took me like a thousand years to realize that the end is [x] and not []... i've learned this...how many times? fuck my life. if this is bad then i am sorry

mergesort.hs

merge xs [] = xs
merge [] xs = xs
merge (x:xs) (y:ys)
  | x > y     = y:(merge (x:xs) ys)
  | otherwise = x:(merge xs (y:ys))
mergesort [] = []
mergesort [x] = [x]
mergesort xs = merge (mergesort (take n xs)) (mergesort (drop n xs))
  where n = (length xs) `div` 2