Rust与Javascript的使用对比

一、常量

Rust	Javascript
let	const

二、变量

Rust	Javascript
let mut	let / var

三、常用打印

Rust	Javascript
println!(“换行”);	console.log(‘hello’);
print!(“不换行”);	console.info(‘信息’);
-	console.error(‘错误’);
-	console.warn(‘警告’);

四、定义字符串

Rust	Javascript
let a = String::from(“xxx”);	let a = “xxx”;

五、定义类json

Rust

fn main() {
    let user: User = User {
        username: String::from("Tom"),
        email: String::from("XXX@qq.com"),
        sign_in_count: 9,
        active: true
    };
    println!("{:?}", user);
    println!("{}", user.username);
    println!("{}", user.email);
    println!("{}", user.sign_in_count);
    println!("{}", user.active);
}

// `#[derive(Debug)]` 是 Rust 中的一个属性（attribute），用于自动生成实现 `Debug` trait 的代码。该属性可以应用于结构体、枚举和联合体等类型。
#[derive(Debug)]
struct User {
    username: String,
    email: String,
    sign_in_count: u64,
    active: bool
}

Javascript

const user = {
    username: "Tom",
    email: "XXX@qq.com",
    sign_in_count: 9,
    active: true
}

console.log(user)

六、循环中的break

Rust

fn main() {
    let arr: [&str; 5] = ["L", "C", "W", "A", "I"];

    let mut i = 0;

    let lo = loop {
        let w = arr[i];

        if w == "W" {
            break i;
        }
        
        i += 1;
    };

    println!("{}", lo);
}

Javascript

const arr = ["L", "C", "W", "A", "I"];

let lo = 0

for (let i=0; i < arr.length; i += 1) {
    let w = arr[i];

    if (w == "W") {
        lo = i
        break
    }
};

console.log(lo)

七、条件语句

Rust 中的条件表达式必须是 bool 类型，否则报错

正确的如下

fn main() {
    let a = 10;

    if a > 0 {
        println!("a is more than 0")
    }
}

Javascript中的条件表达式则没那么严格

const a = 10

if (a) {
    console.log("a is true")
}

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后面待续