Nodejs Array ForEach forEach

Method Source Code

===

Related

1. forEach()

   Array.prototype.forEach = Array.prototype.forEach || _forEach
   Array.prototype.every = Array.prototype.every || _every
   Array.prototype.indexOf = Array.prototype.indexOf || function(member) {
     for(var idx = 0; idx < this.length; ++idx) {
       if(this[idx] === member) {
         return idx
     return -1
   ...
   

2. forEach(a)

   "use strict"
   Array.prototype.forEach = function(a) {
     for (let i = 0; i < this.length; i++) a(this[i], i, this)
   

3. forEach(action, index)

   Array.prototype.forEach = Array.prototype.forEach || function(action, index) {
       for (var i=0,l=this.length; i<l; i++) {
           action(this[i], index);
   };
   

4. forEach(callback)

   Array.prototype.forEach = function(callback){
       let arr = this;
       for (var i = 0; i < arr.length; i++) {
           callback(arr[i], i, arr);