问在函数&self或&mut self中进行模式匹配时，如何避免ref关键字？

EN

struct OwnBox(i32);

impl OwnBox {
    fn ref_mut(&mut self) -> &mut i32 {
        match *self {
            OwnBox(ref mut i) => i,
        }

        // This doesn't work. -- Even not, if the signature of the signature of the function is
        // adapted to take an explcit lifetime 'a and use it here like `&'a mut i`.
        // match *self {
        //     OwnBox(mut i) => &mut i,
        // }

        // This doesn't work
        // match self {
        //     &mut OwnBox(mut i) => &mut i,
        // }
    }
}