javascript - 'Function' 上的 MDN 描述感到困惑，Function.length 是 Function 或 Function.prototype 的属性

Question

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function

据说

Properties and Methods of Function 

The global Function object has no methods or properties of its own, however, since it is a function itself it does inherit some methods and properties through the prototype chain from Function.prototype.

然后它继续说

Function prototype object 
Properties

Function.arguments 
An array corresponding to the arguments passed to a function. This is deprecated as property of Function, use the arguments object available within the function instead.
Function.arity 
Used to specifiy the number of arguments expected by the function, but has been removed. Use the length property instead.
Function.caller 
Specifies the function that invoked the currently executing function.

Function.length (!!!here is what I confused, why it does not display Function.prototype.length)

Specifies the number of arguments expected by the function.
Function.name
The name of the function.
Function.displayName 
The display name of the function.

Function.prototype.constructor

Specifies the function that creates an object's prototype. See Object.prototype.constructor for more details.
Methods

只是想知道 Function.length 是否是 Function.prototype 的属性？

欢迎您发表评论

Answer 1

来自MDN docs on Function.length :

The Function constructor is itself a Function object. Its length data property has a value of 1.

Function.length 等于 1，因为 Function 构造函数采用一个形式参数 - 函数体。

The length property of the Function prototype object has a value of 0.

Function.prototype.length 等于 0，因为 Function.prototype 不接受任何参数。