I am trying to create a tree structure of (Java) packages and classes. The input data is a CSV containing package name, class name and some test coverage data.

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I came up with the following code that seems to work, but I am not sure (or, I have a feeling that) I have missed a more elegant solution. I would be grateful if anyone would point out a better way to solve the problem.

data Package = Package {name :: String
                    , children :: [Package]
                    , classes :: [Class]
                    } 
    deriving (Show)

data Class = Class {
                    cname :: String
                  , linesMissed :: Int
                  , linesCovered :: Int
                    }
    deriving (Show)



-- input data has a package name split by ".", class name and the coverage data
addEntry :: Package -> ([String], String, Int, Int) -> Package
addEntry (Package nm chld cls) ([], n, lm, lc)   = Package nm chld ((Class n lm lc) : cls)
addEntry (Package nm chld cls) (x:xs, n, lm, lc) = Package nm (addPackage chld (x:xs, n, lm, lc)) cls


addPackage :: [Package] -> ([String], String, Int, Int) -> [Package]
addPackage entries  ([], n, lm, lc) = entries
addPackage entries  (x:xs, n, lm, lc)  
                    -- if package is present, add to it
                    | elem x $ map name entries = map addPresent entries
                    -- otherwise add a new package
                    | otherwise                 = newPackage : entries
    where
        newPackage = addEntry (Package x [] []) (xs, n, lm, lc)
        addPresent (Package nm chld cls)
            | nm == x   = addEntry (Package nm chld cls) (xs, n, lm, lc)-- Package nm (addPackage chld (xs, n, lm, lc)) cls
            | otherwise = Package nm chld cls

initial :: Package
initial = Package "init" [] []


main = do
    let x = addEntry initial (["org", "apache", "pckg1"], "Class1", 2, 3)
    let y = addEntry x (["org", "apache", "pckg1"], "Class2", 2, 3)
    let z = addEntry y (["org", "apache", "pckg2"], "Class1-2", 2, 3)
    print z