[Rust] public and private methods

// We use mod to create a non-public block
mod lib {
    pub struct Car;

    impl Car {
        // Public method
        pub fn run(& self) {
            // Call private method
            self.drive();
        }
    }

    impl Car {
        // Private method
        fn drive(& self) {
            println!("Driving a car...");
        }
    }
}

fn main() {
    let car = lib::Car{};
    car.run();
}