Rust编程语言入门教程（Rust语言/Rust权威指南配套）【已完结】

15.4 如下代码可执行 讲错了 并不一定要用rc

use crate::List::{Cons, Nil};

fn main() {

    let list = Cons(1, &Cons(2, &Cons(3, &Nil)));

    let a = Cons(1, &Nil);

    let b = Cons(2, &a);

    let c = Cons(3, &a);

    println!("{:?}", a);

    println!("{:?}", b);

    println!("{:?}", c);

}

#[derive(Debug)]

enum List<'a> {

    Cons(i32, &'a List<'a>),

    Nil,

}