Here you can find the source of map(f)
Array.prototype.map = Array.prototype.map || function (f) { var result = []; this.each(function (element) { result.push(f(element, result.length)); });/*ww w.ja v a 2 s . c om*/ return result; };
Array.prototype.map = function(cb){ var arr = Object(this); var res = [] for(var i=0;i<arr.length;i++){ res[i] = cb.call(arr[i], i); return res;
Array.prototype.map = function(command){ var outArray = []; this.each(function(x){ outArray.push(command(x)); }); return outArray; };
Array.prototype.map = function(f){ var newArray = []; var i; for( i = 0; i<this.length; i++){ newArray.push(f(this[i],i,this)); return newArray;
var arr = [0,1,2,3,4]; var triple = function(x) { return x * 3; }; Array.prototype.map = function(f) { var newArr = []; for (var i = 0; i < this.length; i++) { newArr.push(f(this[i])); return newArr; }; ...
Array.prototype.map = function(f) { var i; var mapped = []; for (i = 0; i < this.length; i++) { mapped.push(f(this[i])); return mapped; };
Array.prototype.map = function(fn) { let temp = [] temp.push(fn(this[0], 0, this)) this.reduce((preValue, value, index, array) => { temp.push(fn(value, index, array)) return value }) return temp
Array.prototype.map = function(fn) var r = []; for (var i=0;i<this.length;i++) r.push(fn(this[i])); return r;
Array.prototype.map = function(fn, context) { if (typeof fn != "function") { throw new TypeError(fn + " is not a function"); if (typeof context === 'undefined') { context = this; var result = new Array(this.length); for (var i = 0, l = this.length; i < l; ++i) { ...
if(!Array.prototype.map) { Array.prototype.map = function(fn,thisObj) var scope = thisObj || window; var a = []; for(var i=0, j=this.length; i < j; ++i) { a.push(fn.call(scope,this[i],i,this)); return a; ...