MDN构造函数属性说明混乱

Question

I'm reading this article about constructor property and it states the following:

Returns a reference to the Object function that created the instance's prototype.

And they give an example:

function Tree(name) {
  this.name = name;
}

var theTree = new Tree('Redwood');
console.log('theTree.constructor is ' + theTree.constructor);

Here the instance is theTree and its prototype is Object.getPrototypeOf(theTree) , which is Object function, not Tree . What am I misunderstanding?

Answer 1

The prototype of an object is typically inherited from its constructor function:

function Tree() {}
Tree.prototype.foo = function () {};

var theTree = new Tree();

theTree now has theTree.foo from its prototype chain . The function Tree initialised the object, and is also responsible for the contents of its prototype chain. That's why they express it as "the Object function that created the instance's prototype" .

Answer 2

Object.getPrototypeOf(theTree) is the prototype of your Tree function

Object.getPrototypeOf(theTree) == Tree.prototype; // true

Both refer the same object

And Tree.prototype has the property named 'constructor' which is infact a reference to the Tree function only

theTree.contructor == Tree.prototype.constructor ;// true

Basically theTree has a proto link (____proto____) and this proto link points to the Tree.prototype. So when you do theTree.constructor it actually follows the proto link and reaches Tree.prototype and finds the constructor which itself it Tree function