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data Content a = Content {
		name :: String,
		value :: a
	} deriving (Show)

data Tree a = Nil
	| Node a (Tree a) (Tree a) deriving (Show)

leaf a = Node a Nil Nil

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tree = Node (Content "Startseite" []) 
	(Node (Content "Tier" []) 
		-- (Leaf (Content "Katze" ["lolcat.jpg"]))
		-- (Leaf (Content "Blattlaus" [])))
		(leaf (Content "Katze" ["lolcat.jpg"]))
		(leaf (Content "Blattlaus" [])))
	(Node (Content "Blume" ["tulpe.png", "lilie.jpg"]) 
		-- (Leaf (Content "Rose" [])) 
		(leaf (Content "Rose" [])) 
		Nil)

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findArticlesByPrefix :: Tree (Content a) -> String -> [Content a]
findArticlesByPrefix Nil _ = []
findArticlesByPrefix (Node a left right) prfx = 
	(findArticlesByPrefix left prfx) ++ /*hier entscheidest du ob der Inhalt in die Liste kommt oder nicht ++ (findArticlesByPrefix right prfx )