My understanding is that the Object.__proto__ is the 'top-level' prototype object in javascript. I would expect its __proto__ to be null, but in Google Chrome (haven't tried other browsers), it isn't. Why is that?

Edit

I know the following image is probably a re-hash of the one below, but I made it myself to check my understanding. Is there anything wrong with it?

My understanding is that the Object.__proto__ is the 'top-level' prototype object in javascript. I would expect its __proto__ to be null, but in Google Chrome (haven't tried other browsers), it isn't. Why is that?

Edit

I know the following image is probably a re-hash of the one below, but I made it myself to check my understanding. Is there anything wrong with it?

• javascript
• prototype

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2 Answers 2

Sorted by: Reset to default 6

Object is a function, it's __proto__ is an empty function function() {}. The root object is an empty object {}, not Object. So, when you have an object like {foo:1, bar:1} its relationships look like this:

I think you're mistaking Object.__proto__ for Object.prototype.

Object.prototype.__proto__ is indeed null, because Object doesn't extend anything.

Object itself, however, is a function - aka. an instance of Function.
Since Function extends Object, it's prototype has a __proto__ property.
You can thus take a detour over Object.__proto__.__proto__ to reach Object.prototype, in fact:

Object.prototype === Object.__proto__.__proto__ // should yield true