- (o, n, []) -> undefined
- (_, _, err) -> Left "invalid"
-
-main = do
- argv <- getArgs
- return 0
+ (o, [n], []) -> return (foldl (flip id) defaultOptions o, n)
+ (o, _, []) -> ioError $ userError $ "must supply input file"
+ (_, _, errs) -> ioError $ userError $ (concat errs)