neighbours :: Grid -> Coord -> [Coord]
neighbours grid here = filter (inRange (bounds grid))
[ here ^+^ delta
| delta <- [V2 -1 0, V2 1 0, V2 0 -1, V2 0 1]
]
neighbours :: Grid -> Coord -> [Coord]
neighbours grid here = filter (inRange (bounds grid))
[ here ^+^ delta
| delta <- [V2 -1 0, V2 1 0, V2 0 -1, V2 0 1]
]