minesweeper.hs

type Point a = (a, a)
type PointFn a = ((a -> a), (a -> a))

data Board a = Board { boardMin :: Point a,
                       boardMax :: Point a }
               deriving (Show)

makeBoard :: (Enum a, Ord a) => Point Int -> Board a
makeBoard (x, y) = Board (z, z) (toEnum x, toEnum y)
                   where z = toEnum 0

neighborFns :: Enum a => [PointFn a]
neighborFns = [(pred, pred),
               (pred, id),
               (pred, succ),
               (succ, pred),
               (succ, id),
               (succ, succ),
               (id, succ),
               (id, pred)]

neighbors :: (Enum a, Ord a) => Point a -> [Point a]
neighbors point = filter inBounds (map (applyNeighborFn point) neighborFns)
                  where applyNeighborFn (x, y) (fx, fy) = (fx x, fy y)
                        inBounds (x, y) = (x >= z) && (y >= z)
                        z = toEnum 0
                        inBounds (x, y) = (x >= z) && (y >= z)
                        z = toEnum 0