qsort [] = []
qsort (h:t) = 
    qsort [x | x <- t, x <= h] ++ [h] ++ qsort [x | x <- t, x > h]
 
data Foo = Foo (Char, Char, Int) deriving (Eq, Show)
 
data Bar = Bar {
	ch1 :: Char,
	ch2 :: Char,
	ord :: Int
} deriving (Eq, Show)
 
instance Ord Foo where
	compare (Foo (_, _, x)) (Foo (_, _, y)) = compare x y
 
instance Ord Bar where
	compare (Bar _ _ x) (Bar _ _ y) = compare x y
 
testDataFoo = [Foo ('d', 'k', 21), Foo ('a', 'b', 1), Foo ('x', 'y', 34)]
testDataBar = [Bar 'd' 'k' 21, Bar 'a' 'b' 1, Bar 'x' 'y' 34]
 
main = do
	print $ qsort testDataFoo
	print $ qsort testDataBar
 

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