Implement Array.forEach


The forEach() method executes a provided function once for each array element.


Implement the Array.forEach method

Thought process Pseudocode

  1. A function which takes a function as an argument
  2. The function argument must be passed the array index, the item and the context
  3. A check should me made to see if the item exists in the array


* Foreach function is attached to the array prototype
* It takes in a callback and passes every item in the array
* through the callback
* The callback gets 3 arguments
* the item, the index and the execution context
* A for each array loop cannot be broken using break;
Array.prototype.newForEach = function (callback, context) {
for (let index = 0; index < this.length; index++) {
// This is primarily to check if the item
// exists in the array,
if (this.indexOf(this[index]) > -1) {, this[index], index, this)
// example
const words = ["adam", "ate", "an", "apple"]
const upperCaseList = []
words.newForEach((word, index, context) => {


The for each loop cannot be broken, in between. In such case where the loop must be exited when a condition is met, Array.some or Array.find me be a better option.