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JavaScript Object.create（）的polyfill，由我完全困惑的代码。代码链接是polyfill of Object create。javascript的polyfill用简单的形式创建对象
if (typeof Object.create != 'function') {
// Production steps of ECMA-262, Edition 5, 15.2.3.5
// Reference: http://es5.github.io/#x15.2.3.5
Object.create = (function() {
// To save on memory, use a shared constructor
function Temp() {}
// make a safe reference to Object.prototype.hasOwnProperty
var hasOwn = Object.prototype.hasOwnProperty;
return function(O) {
// 1. If Type(O) is not Object or Null throw a TypeError exception.
if (typeof O != 'object') {
throw TypeError('Object prototype may only be an Object or null');
}
// 2. Let obj be the result of creating a new object as if by the
// expression new Object() where Object is the standard built-in
// constructor with that name
// 3. Set the [[Prototype]] internal property of obj to O.
Temp.prototype = O;
var obj = new Temp();
Temp.prototype = null; // Let's not keep a stray reference to O...
// 4. If the argument Properties is present and not undefined, add
// own properties to obj as if by calling the standard built-in
// function Object.defineProperties with arguments obj and
// Properties.
if (arguments.length > 1) {
// Object.defineProperties does ToObject on its first argument.
var Properties = Object(arguments[1]);
for (var prop in Properties) {
if (hasOwn.call(Properties, prop)) {
obj[prop] = Properties[prop];
}
}
}
// 5. Return obj
return obj;
};
})();
}- 为什么它通过使用IIFE逻辑复杂（立即调用功能Express）和返回功能，并关闭。
- 相反，我可以使用下面的简单逻辑和代码吗？内容中是否有错误或不恰当的内容？没有IIFE和返回功能。
if (typeof Object.createOwn != "function") {
Object.createOwn = function(O) {
// 1. if Type(O) is not Object or Null throw a TypeError exception.
if (typeof(O) != "object") {
throw TypeError("Object prototype may only be an Object or null");
}
// 2. Let obj be the result of creating a new object as if by the
// expression new Object() where Object is the standard built-in
// constructor with that name
// 3. Set the [[Prototype]] internal property of obj to O.
var obj;
var Temp = function() {};
Temp.prototype = O;
obj = new Temp();
// 4. If the argument Properties is present and not undefined, add
// own properties to obj as if by calling the standard built-in
// function Object.defineProperties with arguments obj and Properties
if (arguments.length > 1) {
var Properties = Object(arguments[1]);
for (var prop in Properties) {
if (Properties.hasOwnProperty(prop)) {
obj[prop] = Properties[prop];
}
}
}
return obj;
}
}
var foo = {
one: 1,
two: 2
};
var bar = Object.createOwn(foo, 3);