astar_grid.rs

    struct Grid2d {
       // your grid goes here, assume that we have an "is_moveable" method implemented on Grid2d
    }
    
    struct Grid2dSearch<'a> {
        grid: &'a Grid2d,
        start: (i32, i32),
        end: (i32, i32)
    }

    impl SearchProblem<(i32, i32), i32, MoveItems<((i32, i32), i32)>> for Grid2dSearch {
        fn start(&self) -> (i32, i32) { self.start }
        fn is_end(&self, p: &(i32, i32)) -> bool { *p == self.end }
        fn heuristic(&self, &(p_x, p_y): &(i32, i32)) -> i32 {
            let (s_x, s_y) = self.end;
            (s_x - p_x).abs() + (s_y - p_y).abs()
        }
        fn neighbors(&self, &(x, y): &(i32, i32)) -> MoveItems<((i32, i32), i32)> {
            let mut vec = vec![];
            for i in range_inclusive(-1, 1) {
                for k in range_inclusive(-1, 1) {
                    if !(i == 0 && k == 0) {
                        if self.grid.is_moveable(x+i, y+k) {
                            vec.push(((x + i, y + k), 1));
                        }
                    }
                }
            }
            vec.into_iter()
        }
    }