{-# LANGUAGE PatternSynonyms #-}

newtype CaseFree = CaseFree_ (String, Int)
  deriving (Show, Eq, Ord)

pattern CaseFree :: String -> Int -> CaseFree
pattern CaseFree a b <- CaseFree_ (a, b)

getStr :: CaseFree -> String
getStr (CaseFree str _) = str

getBits :: CaseFree -> Int
getBits (CaseFree _ bits) = bits

ignore :: CaseFree -> String
ignore (CaseFree _ _) = "Ignored."

main :: IO ()
main = do
  mapM_ putStrLn
    [ getStr (CaseFree_ ("abc", 0))
    , show (getBits (CaseFree_ ("abc", 0)))
    , ignore (CaseFree_ ("foo", 1))
    ]