destructing js code example

Example 1: object destructuring

const book = {
    title: 'Ego is the Enemy',
    author: 'Ryan Holiday',
    publisher: {
        name: 'Penguin',
        type: 'private'
    }
};

const {title: bookName =  'Ego', author, name: {publisher: { name }} = book, type: {publisher: { type }} = book } = book;

Example 2: destructuring assignment

Destructuring assignment is special syntax introduced in ES6, 
for neatly assigning values taken directly from an object.

const user = { name: 'John Doe', age: 34 };

const { name, age } = user;
// name = 'John Doe', age = 34

Example 3: object destructuring

let a, b, rest;
[a, b] = [10, 20];

console.log(a);
// expected output: 10

console.log(b);
// expected output: 20

[a, b, ...rest] = [10, 20, 30, 40, 50];

console.log(rest);
// expected output: Array [30,40,50]

Example 4: javascript destructing

/*
* On the left-hand side, you decide which values to unpack from the right-hand
* side source variable.
* 
* This was introduced in ES6
*/
const x = [1, 2, 3, 4, 5]
const [a, b] = x
console.log(a) // prints out: 1
console.log(b) // prints out: 2

Example 5: mdn destructuring

let a, b;

[a, b] = [1, 2];
console.log(a); // 1
console.log(b); // 2

Example 6: js destructuring explained

const { identifier } = expression;