I need the trick to get from
ByteString -> [GHC.Word.Word8]
and Hayoo is not helping.
 
Super simple I expected.  I haven't even tried to compile it yet.
I am just trying to read in the bytes and encode with base64:
 
import Codec.Binary.Base64
import Data.ByteString
import System.Directory
import System.Environment
main :: do
        args <- getArgs
        bFileExist <- System.Directory.doesFileExist (args !! 0)
        let bytedata = --ByteString -> [GHC.Word.Word8]
        if bFileExist then putStrLn $ Codec.Binary.Base64.encode bytedata
        else putStrlLn ("File does not exist: " ++ (args !! 0))
        return ()