not_ok.rs

#[derive(Debug)]
struct Point {
    x: f32,
    y: f32,
}

#[derive(Debug)]
struct Rectangle {
    p1: Point,
    p2: Point,
}

fn square(point: Point, side: f32) -> Rectangle {
    Rectangle{ p1: point, p2: Point{ x: point.x + side, y: point.y + side} }
}

fn main() {
    let point: Point = Point { x: 0.3, y: 0.4 };
    println!("Square: {:?}", square(point, 1f32));
}

ok.rs

#[derive(Debug)]
struct Point {
    x: f32,
    y: f32,
}

#[derive(Debug)]
struct Rectangle {
    p1: Point,
    p2: Point,
}

fn square(point: Point, side: f32) -> Rectangle {
    Rectangle{ p2: Point{ x: point.x + side, y: point.y + side}, p1: point }
}

fn main() {
    let point: Point = Point { x: 0.3, y: 0.4 };
    println!("Square: {:?}", square(point, 1f32));
}