destructor in javascript code example

Example 1: javascript object destructuring

//simple example with object------------------------------
let obj = {name: 'Max', age: 22, address: 'Delhi'};
const {name, age} = obj;

console.log(name);
//expected output: "Max"

console.log(age);
//expected output: 22

console.log(address);
//expected output: Uncaught ReferenceError: address is not defined

// simple example with array-------------------------------
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 2: Destructuring Assignment

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

//ES6 assignment syntax
const {today, tomorrow} = HIGH_TEMPERATURES;

//ES5 assignment syntax
const today = HIGH_TEMPERATURES.today;
const tomorrow = HIGH_TEMPERATURES.tomorrow;

console.log(today); // 77
console.log(tomorrow); // 80
console.log(yesterday); // "ReferenceError: yesterday is not defined" as it should be.

Example 3: destructure array javascript

var [first, second, ...rest] = ["Mercury", "Earth", ...planets, "Saturn"];

Example 4: js destructuring explained

const { identifier } = expression;

Example 5: array destructuring in javascript

const array = ['ismail', 'sulman'];
// array destructuring
const [firstElement, secondElement] = array;
console.log(firstElement, secondElement);
const secondArray = ['ismail', 'naeem', 'Mr', 1];
const [firstEl, secondEl, ...array1] = secondArray;
console.log(firstEl, secondEl, array1);