Dec 2, 2018 · Dec 2, 2018
diff --git a/2018/01_1/idris/appositum.idr b/2018/01_1/idris/appositum.idr
 import Data.String

 subtract : Neg a => a -> a -> a
 subtract x y = y - x

 parse : List Char -> Integer -> Integer
 parse (x::xs) =
  case parseInteger (pack xs) of
    Nothing => id
    Just num =>
      case x of
        '+' => (+num)
        '-' => subtract num

 loop : Integer -> List (List Char) -> Integer
 loop acc lst = foldl (\x, f => f x) acc (map parse lst)

 main : IO ()
 main = do
  args <- getArgs
  case args of
    (_::arg::_) => do
      file <- readFile arg
      case file of
        Right res => print $ loop 0 $ map unpack (lines res)
        Left _ => putStrLn "File not found"
    _ => putStrLn "Usage: ./appositum input.txt"
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,27 @@
		import Data.String

		subtract : Neg a => a -> a -> a
		subtract x y = y - x

		parse : List Char -> Integer -> Integer
		parse (x::xs) =
		case parseInteger (pack xs) of
		Nothing => id
		Just num =>
		case x of
		'+' => (+num)
		'-' => subtract num

		loop : Integer -> List (List Char) -> Integer
		loop acc lst = foldl (\x, f => f x) acc (map parse lst)

		main : IO ()
		main = do
		args <- getArgs
		case args of
		(_::arg::_) => do
		file <- readFile arg
		case file of
		Right res => print $ loop 0 $ map unpack (lines res)
		Left _ => putStrLn "File not found"
		_ => putStrLn "Usage: ./appositum input.txt"