shim.js
648 Bytes
'use strict';
var isPlainArray = require('../../is-plain-array')
, callable = require('../../../object/valid-callable')
, isArray = Array.isArray, map = Array.prototype.map
, forEach = Array.prototype.forEach, call = Function.prototype.call;
module.exports = function (callbackFn/*, thisArg*/) {
var result, thisArg;
if (!this || !isArray(this) || isPlainArray(this)) {
return map.apply(this, arguments);
}
callable(callbackFn);
thisArg = arguments[1];
result = new this.constructor(this.length);
forEach.call(this, function (val, i, self) {
result[i] = call.call(callbackFn, thisArg, val, i, self);
});
return result;
};