decide :: Opts -> HisgM ()
decide opt =
    case opt of
        Help -> liftIO $ putStrLn usage
        Version -> liftIO $ putStrLn exactVersion
        File fn -> loadFile fn
decide :: Opts -> HisgM ()
decide opt =
    case opt of
        Help -> liftIO $ putStrLn usage
        Version -> liftIO $ putStrLn exactVersion
        File fn -> loadFile fn
decide opt =
    case opt of
        Help -> liftIO $ putStrLn usage
        Version -> liftIO $ putStrLn exactVersion
        File fn -> loadFile fn