greet :: Flag "g" '["greet"] "STRING" "greeting message" (Def "Hello" String)
      -> Flag "" '["decolate"] "" "decolate message" Bool
      -> Arg "NAME" String
      -> Cmd "Greeting command" ()
greet msg deco name = do
    let f x | get deco = "*** " ++ x ++ " ***"
            | otherwise = x
    liftIO $ putStrLn $ f $ get msg ++ ", " ++ get name ++ "!"
greet :: Flag "g" '["greet"] "STRING" "greeting message" (Def "Hello" String)
      -> Flag "" '["decolate"] "" "decolate message" Bool
      -> Arg "NAME" String
      -> Cmd "Greeting command" ()
greet msg deco name = do
    let f x | get deco = "*** " ++ x ++ " ***"
            | otherwise = x
    liftIO $ putStrLn $ f $ get msg ++ ", " ++ get name ++ "!"
greet msg deco name = do
    let f x | get deco = "*** " ++ x ++ " ***"
            | otherwise = x
    liftIO $ putStrLn $ f $ get msg ++ ", " ++ get name ++ "!"