packStringST :: [Char] -> ST s (ByteArray Int)
packStringST str =
  let len = length str  in
  packNBytesST len str
packStringST :: [Char] -> ST s (ByteArray Int)
packStringST str =
  let len = length str  in
  packNBytesST len str
packStringST str =
  let len = length str  in
  packNBytesST len str