[Haskell-beginners] Creating beautiful code: can you make this divide-and-conquer implementation of the "tails" function beautiful?

[Costello, Roger L.]

Hi Folks,

Below is a divide-and-conquer implementation of the "tails" function. 

Notice the two patterns (x:y:xs) and (x:[]). And notice that (x:y:xs) is used by the "length" function and again by the "splitAt" function. That doesn't seem elegant. Can the function be simplified and made beautiful?  

/Roger


tails'               ::   [a] -> [[a]]
tails' (x:y:xs)   =   map (++zs) (tails' ys) ++ tails' zs
                           where m        =  length (x:y:xs)
                                       n         =  m `div` 2
                                      (ys,zs)  =  splitAt n (x:y:xs)
tails' (x:[])      =    [[x]]