js 可否进行多个声明与赋值

let a, b, c;

let a = 1, b = 2, c = 3;

let a = 1, b, c = 3;

console.log(a); // undefined
var a = 1;

let a = 1;
let a = 2; // SyntaxError: Identifier 'a' has already been declared

let [a, b = 2, c] = [1]; // a = 1, b = 2, c = undefined

// 多重声明与赋值
let x = 1, y = 2, z = 3;

// 解构赋值
let [p, q, r] = [4, 5, 6];

// 函数返回多个值
function getCoordinates() {
    return { x: 10, y: 20 };
}
let { x: coordX, y: coordY } = getCoordinates();

console.log(x, y, z); // 1 2 3
console.log(p, q, r); // 4 5 6
console.log(coordX, coordY); // 10 20