fn takes_option(opt: Option<i32>) {
    println!("{:?}", opt);
}

fn also_takes_option(Some(value): Option<i32>) {
    println!("{:?}", value);
}

fn main() {
    takes_option(Some(1));
    also_takes_option(Some(2));
    //also_takes_option(None); -> refutable pattern in function argument: `None` not covered
}