🔰destructuring array

JS ⟩ operator ⟩ assignment ⟩ destructuring ⟩ array

let [a, b] = [1, 2, 3]
let [a, ...rest] = array

💾 程式

💾 程式：replit

// array destructuring
let [a, b] = ["John", "Smith"]
let [a, b] = "John Smith".split(' ')

let [a, , c] = ["hi","what","hello"];  // ⭐ ignore elements
let [a, b, ...rest] = "abcdef"         // ⭐ "rest" (array)
let [s, t = 0] = [1];                  // ⭐ default values

let [
    name = prompt('name?'),            // ⭐ return value as default
    surname = prompt('surname?')
] = ["Julius"];

// tricks

// ⭐ assign to object's properties
let user = {};
[user.name, user.surname] = "John Smith".split(' ');
// user = { name: 'John', surname: 'Smith' }

// ⭐ "swap" trick
let [p, q] = [1, 2];
[p, q] = [q, p];                     // p=2, q=1

📗 參考

• JS.info ⟩ array destructuring

👥 相關

• nested destructuring

⬇️ 應用

• A1NotationToRowColumn() - "AA3" to [ "AA", "3" ].