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.
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
let profile = ['bob', 34, 'carpenter'];let [name, age, job] = profile;console.log(name);--> 'bob'
const [firstElement, secondElement] = list;
// is equivalent to:
// const firstElement = list[0];
// const secondElement = list[1];
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment
// destructuring assignment in javascript
// object destructuring
let person = {
name: "Chetan",
age: 30,
country: "India"
};
const { name, age } = person;
console.log(name);
//expected output: "Chetan"
console.log(age);
//expected output: 30
console.log(country);
//expected output: Uncaught ReferenceError: country is not defined
// Array destructuring
const num = [1,2,3];
const [one, two, three] = num;
console.log(one); // 1
console.log(two); // 2
console.log(three); // 3