never executed always true always false

    1 module HelVM.HelMA.Automata.Piet.Types.Image (
    2   witdthImage,
    3   heightImage,
    4   inRangeImage,
    5   pixelImage,
    6   setPixelImage,
    7   newImage,
    8   Image(..),
    9 ) where
   10 
   11 import           HelVM.HelMA.Automata.Piet.Types.Coordinates
   12 
   13 import           Data.Array.Diff
   14 
   15 witdthImage :: Image a -> Int
   16 witdthImage = fst . dimensionsImage
   17 
   18 heightImage :: Image a -> Int
   19 heightImage = snd . dimensionsImage
   20 
   21 dimensionsImage :: Image a -> Coordinates
   22 dimensionsImage (Image pixels) = (maxX - minX + 1, maxY - minY + 1) where ((minX, minY), (maxX, maxY)) = bounds pixels
   23 
   24 inRangeImage :: Coordinates -> Image a -> Bool
   25 inRangeImage (x, y) img = 0 <= x && x < witdthImage img && 0 <= y && y < heightImage img
   26 
   27 pixelImage :: Coordinates -> Image a -> a
   28 pixelImage (x, y) img = pixels img ! (x, y)
   29 
   30 setPixelImage :: Coordinates -> a -> Image a -> Image a
   31 setPixelImage (x, y) pixel img = img { pixels = pixels img // [((x, y), pixel)] }
   32 
   33 newImage :: Coordinates -> [(Coordinates, a)] -> Image a
   34 newImage (width, height) = Image . array ((0, 0), (width - 1, height - 1))
   35 
   36 instance Functor Image where
   37   fmap f img = img { pixels = amap f (pixels img) }
   38 
   39 newtype Image a = Image
   40   { pixels :: DiffArray Coordinates a
   41   }
   42   deriving stock (Show)