#![allow(dead_code, deprecated, unused_variables, unused_mut)]
fn check_optional(optional: Option<Box<i32>>) {
    match optional {
        Some(p) => println!("has value {p}"),
        None => println!("has no value"),
    }
}
fn main() {
    let optional = None;
    check_optional(optional);
    let optional = Some(Box::new(9000));
    check_optional(optional);
}