How to implement methods on struct

Implement methods on a struct by defining an impl block for the struct type and adding functions where the first parameter is self.

struct Point {
    x: i32,
    y: i32,
}

impl Point {
    fn distance(&self, other: &Point) -> f64 {
        let dx = other.x - self.x;
        let dy = other.y - self.y;
        (dx * dx + dy * dy) as f64 .sqrt()
    }
}

The &self parameter allows the method to borrow the instance without taking ownership, enabling you to call distance on a Point instance like p1.distance(&p2).

An impl block is a container that holds functions specifically designed to work with a particular struct. Think of it as adding custom actions or tools directly to a specific type of object, like adding a 'start engine' button to a car blueprint. You use this whenever you need your data structure to perform specific operations on itself.