What does the $mul operator do?

In Rust, the $mul operator is not a standard operator. However, if you are referring to the multiplication operator *, it is used to multiply two values.

In the context of operator overloading, you can overload the multiplication operator by implementing the Mul trait from the std::ops module. Here’s an example of how to overload the * operator for a custom struct:

use std::ops::Mul;

#[derive(Debug, Copy, Clone)]
struct Point {
    x: i32,
    y: i32,
}

impl Mul for Point {
    type Output = Point;

    fn mul(self, other: Point) -> Point {
        Point {
            x: self.x * other.x,
            y: self.y * other.y,
        }
    }
}

fn main() {
    let p1 = Point { x: 2, y: 3 };
    let p2 = Point { x: 4, y: 5 };
    let result = p1 * p2;
    println!("{:?}", result); // Output: Point { x: 8, y: 15 }
}

In this example, the mul method multiplies the x and y values of two Point instances to create a new Point.