Enum with Data + match

enum Event {
    Click  { x: i32, y: i32 },
    Scroll(f64),
    KeyPress(char),
    Quit,
}

fn handle(event: Event) {
    match event {
        Event::Click { x, y }   => println!("click at ({x}, {y})"),
        Event::Scroll(delta)    => println!("scrolled {delta:+.1}"),
        Event::KeyPress(c)      => println!("key: {c}"),
        Event::Quit             => println!("bye"),
        // Adding a new variant later forces every match site to update.
    }
}

fn main() {
    handle(Event::Click { x: 10, y: 20 });
    handle(Event::Scroll(-3.5));
    handle(Event::KeyPress('q'));
    handle(Event::Quit);
}