Finding repeatings in lists

r.hs

import Prelude()
import Prelude.Plus

type Repeating = []

findRepeatings :: Eq a => [a] -> [Repeating a]
findRepeatings = concatMap findRepeatingsStartFromHere . tails

findRepeatingsStartFromHere :: Eq a => [a] -> [Repeating a]
findRepeatingsStartFromHere =
    map fst
  . filter (uncurry isPrefixOf)
  . uncurry zip
  . (tail . inits &&& tail . tails)

findRepeatingsWithIndices :: (Eq a) => [a] -> [(Int,Repeating a)]
findRepeatingsWithIndices =
    concatMap (uncurry zip . (repeat *** findRepeatingsStartFromHere))
  . zip [0..]
  . tails

type Colony = []

allSublistOf :: [a] -> [[a]]
allSublistOf = ([]:) . (tails >=> tail . inits)

has :: (Eq a) => [a] -> a -> Int
has haystack needle = length . filter (==needle) $ haystack

findColony :: (Eq a) => a -> [a] -> Colony a
findColony needle haystack = let hasNeedle = (`has` needle) in
    minimumBy (comparing length) . head
  . groupBy ((==) `on` hasNeedle) . reverse . sortBy (comparing hasNeedle)
  . allSublistOf $ haystack