washing haskell for steffen

import Test.QuickCheck
import Data.List
 
-- Contract
sortWashing :: Eq a => [a] -> [[a]]
 
-- Purpose
-- Takes a list of clothes and sorts them into groups which can be washed together.
-- This might help Steffen to find out what can be washed together.
 
-- Examples
-- sortWashing ["Boxershort", "T-Shirt", "T-Shirt"] : [["T-Shirt", "T-Shirt"], ["Boxershort"]]
 
-- Definition
sortWashing xs = group xs
 
-- Test
prop_purity xs = and [ True | f:s:ys <- sortWashing xs, f == s]
	where types = (xs :: [Char])