Lib.rs

所以这个

#[derive(New)]
struct Cube {
	r: i32,
	c: i32,
	z: i32,
	w: i32,
}

... 将创建这个

impl Cube {
    const fn new(r: i32, c: i32, z: i32, w: i32) -> Self {
        Self { r, c, z, w }
    }
}

备注：Rust Analyzer 已经为您生成了 new 函数！

https://rust-analyzer.github.io/manual.html#assists-code-actions

备注2：我发现（2023-11-12）另一个已经做这件事的crate！=) 很有趣的是，它有相同的名字，但是顺序颠倒了：derive-new

它比这个更强大，因为它处理默认值、枚举和 PhantomData。
尽管 此crate创建一个 const fn，而 derive-new 则没有。

使用方法

https://crates.io/crates/new-derive

cargo add new-derive

`use new_derive::New;

#[derive(New)]
struct Cube {
    r: i32,
    c: i32,
    z: i32,
    w: i32,
}

#[derive(Debug, New)]
struct V {
    b: Vec<String>,
}

#[derive(Debug, New)]
struct B {
    b: Box<String>,
}

#[derive(Debug, New)]
struct S1 {
    array1: [i32; 3],
    name: String,
}

#[derive(Debug, New)]
struct S2 {
    opt1: Option<String>,
    idx: usize,
    map1: std::collections::HashMap<i32, i32>,
}

#[derive(Debug, New)]
struct Life1<'a> {
    name: &'a str,
}

fn main() {
    let cube = Cube::new(1, 2, 3, 4);
    println!("{}", cube.r * cube.c * cube.z * cube.w);

    let s1 = S1::new([1, 2, 3], "Leandro".into());
    dbg!(s1);

    let map1 = std::collections::HashMap::from([(10, 20)]);
    let s2 = S2::new(Some("ola".into()), 30, map1);
    dbg!(s2);

    let country = "Brazil";
    let lifetime_test = Life1::new(country);
    println!("Country is: {}", lifetime_test.name);
}

输出

24
[src/main.rs:44] s1 = S1 {
    array1: [
        1,
        2,
        3,
    ],
    name: "Leandro",
}
[src/main.rs:48] s2 = S2 {
    opt1: Some(
        "ola",
    ),
    idx: 30,
    map1: {
        10: 20,
    },
}
Country is: Brazil