js arry shift code example

Example 1: array shift javascript

//The shift() method removes the first element from an array 
//and returns that removed element. 
//This method changes the length of the array.

const array1 = [1, 2, 3];
const firstElement = array1.shift();
console.log(array1);
// expected output: Array [2, 3]
console.log(firstElement);
// expected output: 1

Example 2: insert element at beginning of array javascript

// Use unshift method if you don't mind mutating issue
// If you want to avoid mutating issue
const array = [3, 2, 1]

const newFirstElement = 4

const newArray = [newFirstElement].concat(array) // [ 4, 3, 2, 1 ]

console.log(newArray);