| c == "G" || c == "g" = truncate (n * 1000 * 1000 * 1000)
| otherwise = throwDyn (CmdLineError ("can't decode size: " ++ str))
where (m, c) = span pred str
| c == "G" || c == "g" = truncate (n * 1000 * 1000 * 1000)
| otherwise = throwDyn (CmdLineError ("can't decode size: " ++ str))
where (m, c) = span pred str