In this post, we will see how to use the spread operator in JavaScript.

The spread operator is introduced in ES6.

In this post, we will see some common use cases of spread operator.

1. Copy an array

// array 1
const  a1  = [1,2,3];

// This creates a copy of array a1 and assignes to new array a2
const a2 = [...a1];

console.log(a2); // prints [1,2,3]

2. Merge arrays

const a1 = [1,2,3];
const a2 = [4,5,6];
const a3 = [...a1, ...a2]; // [1,2,3,4,5,6]

3. Create an object

const ob1 = {
	name: "Hey",
	age: 20
};

const ob2 = {...ob1};

console.log(ob2);

/* output : {
	name: "Hey",
	age: 20
}; */

4. Merge objects

const ob1 = {
	name: "Hey",
	age: 20,
};

const ob2 = {
	gender: "male",
};

const ob3 = {...ob1,...ob2};

console.log(ob3);
/* output : {
	name: "Hey",
	age: 20,
	gender: "male",
} */