#9 Polishing shuffle

lib/Shuffle.hs

@@ -1,12 +1,23 @@
-module Shuffle (
-    shuffle
+module Shuffle
+( shuffle
 ) where
 
 import Data.List
 import System.Random
 
+----------------------------------------------------------------------
+-- Shuffle a list so that the elements of the list are randomly     --
+-- perumated.                                                       --
+----------------------------------------------------------------------
+
+----------------------------- Constants ------------------------------
+
+-- The seed used to generate random numbers.
+seed :: Int
 seed = 20
 
+----------------------------------------------------------------------
+
 -- Shuffle a list of values.
 shuffle :: [a] -> [a]
 shuffle l = map (l !!) $ generateIndices $ length l
@@ -19,6 +30,5 @@ generateIndices size = take size uniqueList
           uniqueList = nub randomList
 
 -- Generate a random generator
--- TODO Écht random maken?
 randomGen :: StdGen
 randomGen = mkStdGen seed