[Rust] C-style object

struct Point {
    x: f64,
    y: f64,
}

fn point_new(x: f64, y: f64) -> Point {
    Point{ x: x, y: y }
}

fn point_get_x(p: & Point) -> f64 {
    (*p).x
}

fn point_get_y(p: & Point) -> f64 {
    (*p).y
}

fn point_set_x(p: &mut Point, x: f64) {
    (*p).x = x;
}

fn point_set_y(p: &mut Point, y: f64) {
    (*p).y = y;
 }

fn point_to_string(p: & Point) -> String {
    format!("({}, {})", point_get_x(p), point_get_y(p))
}

fn main() {
    let mut p = point_new(0.0, 0.0);
    assert_eq!(point_to_string(&p), "(0, 0)");

    point_set_x(&mut p, 3.0);
    point_set_y(&mut p, 4.0);
    assert_eq!(point_to_string(&p), "(3, 4)");
}