main :: IO ()
main = do
    opts <- getOpts
    if (null (inputs opts))
      then showUsage
      else runMain (compileMain opts)
main :: IO ()
main = do
    opts <- getOpts
    if (null (inputs opts))
      then showUsage
      else runMain (compileMain opts)
main = do
    opts <- getOpts
    if (null (inputs opts))
      then showUsage
      else runMain (compileMain opts)