wallN  :: DLevel -> Point -> Bool
wallN lvl (x,y) = maybe False isWall (findTileAt (x, y - 1) lvl)
wallN  :: DLevel -> Point -> Bool
wallN lvl (x,y) = maybe False isWall (findTileAt (x, y - 1) lvl)
wallN lvl (x,y) = maybe False isWall (findTileAt (x, y - 1) lvl)