enum Simple {
    First,
    Second,
    Third,
}

fn main() {
    let v = Simple::First;
    match v {
        Simple::First => println!("1"),
        n => match n {
            Simple::Second => println!("2"),
            Simple::Third => println!("3"),
            // ใ“ใ‚Œ๐Ÿ‘‡ใŒๅฟ…่ฆใชใฎใ‚ˆใใ‚ใ‹ใ‚‰ใชใ„
            Simple::First => unreachable!(),
        },
    }
}

0

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