 = do Opts <$> sflg <*> (many1 $ try field) <*> (try(filename) <|> return "-")

sf
args = do Opts <$> sflg <*> (many1 $ try field) <*> (try(filename) <|> return "-")
args = do Opts <$> sflg <*> (many1 $ try field) <*> (try(filename) <|> return "-")