问题描述
来自：
两者之间的关系有哪些细节？我通过ECMA 262浏览了所有我读过的内容如下：
What are the details of the relationship between the two? I've browsed through ECMA 262 and all I've read there is stuff like:
本机ECMAScript对象有一个名为[[Prototype]]的内部属性。该属性的值为null或对象，用于实现继承。
Native ECMAScript objects have an internal property called [[Prototype]]. The value of this property is either null or an object and is used for implementing inheritance.
每个内置函数和每个内置构造函数都有Function原型对象，这是表达式Function.prototype的初始值
Every built-in function and every built-in constructor has the Function prototype object, which is the initial value of the expression Function.prototype
每个内置原型对象都有Object原型对象，它是表达式
的初始值Object.prototype（15.3.2.1），作为其内部[[Prototype]]属性的值，除了Object
原型对象本身。
Every built-in prototype object has the Object prototype object, which is the initial value of the expression Object.prototype (15.3.2.1), as the value of its internal [[Prototype]] property, except the Object prototype object itself.
从这一切我收集到的是[[Prototype]]属性相当于几乎任何对象的 prototype 属性。我错了吗？
From this all I gather is that the [[Prototype]] property is equivalent to the prototype property for pretty much any object. Am I mistaken?
推荐答案
我相信你在大多数情况下是对的。
I believe you are right in most cases.
每个对象都有一个隐藏的 [[Prototype]] 属性，用于继承。函数还有一个公共 prototype 属性，仅当函数用作构造函数时才使用：当使用 new ，新对象的 [[Prototype]] 属性设置为函数的 prototype 属性用作构造函数。
Every object has a hidden [[Prototype]] property, which is used for inheritance. Functions additionally have a public prototype property, which is used only when the function is used as constructor: When an object is constructed using new, the [[Prototype]] property of the new object is set to the prototype property of the function that was used as constructor.
例如
function C() {}
C.prototype = P1;
var obj = new C(); // obj.[[Prototype]] is now P1.
你可以得到 [[Prototype]] 使用 Object.getPrototypeOf（< obj>）的属性。 （此方法在ECMAScript 5中指定。较旧版本的JavaScript没有任何标准方法来读取 [[Prototype]] ）。
You can get the [[Prototype]] property using Object.getPrototypeOf(<obj>). (This method is specified in ECMAScript 5. Older versions of JavaScript does not have any standard way of reading [[Prototype]]).
你可以通常通过构造函数获取原型，例如：
You can usually get to the prototype through the constructor, e.g.:
obj.constructor.prototype == Object.getPrototypeOf(obj)
但情况并非如此，因为可以重新分配构造函数的prototype属性，但是在创建对象后无法重新分配对象的 [[Prototype]] 。所以如果你这样做：
But this is not always the case, since the prototype property of the constructor function can be reassigned, but the [[Prototype]] of an object cannot be reassigned after the object is created. So if you do:
C.prototype = P2;
然后
obj.constructor.prototype != Object.getPrototypeOf(obj)
因为原型 C 现在 P2 ，但 [[原型]] obj 仍为 P1 。
Because the prototype of C is now P2, but [[Prototype]] of obj is still P1.
请注意是仅具有原型属性的函数。另请注意，函数的 prototype 属性与函数的 [[Prototype]] 属性不同！
Note that it is only functions that have a prototype property. Note also that the prototype property of a function is not the same as the [[Prototype]] property of the function!
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