JAVASCRIPT

How javascript spread operator works?

var num = [2, 4, 6, 8, 10];
console.log(...num)
//expected output: 2 4 6 8 10
console.log(88, ...num, 99) 
// added extra new elements before and after the spread operator
//expected output: 88 2 4 6 8 10 99

Spread Syntax for function

myFunction(...iterableObj); // pass all elements of iterableObj as arguments to function myFunction

Spread syntax in ES6

let arr1 = [1, 2, 3]
let func = (a, b, c) => a + b + c

console.log(func(...arr1)) // 6

How to Use the Spread Operator in JavaScript

const newArray = ['firstItem', ...oldArray];

Spread syntax (...)

myFunction(a, ...iterableObj, b)
[1, ...iterableObj, '4', 'five', 6]
{ ...obj, key: 'value' }