Is there a way to hide Object.prototype's property?

Question

If I add a property to Object.prototype like Object.prototype.sth = "something";

then, is there a way to hide the property for a specified object? I tried like this:

function Foo() {
// sth...
}
Foo.prototype = null;
var bar = new Foo();

however, bar still have access to the property sth;

bar.__proto__ = null or Foo.prototype.__proto__ = null works

It's not possible, but you can take a look at this answer: http://stackoverflow.com/a/2636719/2183827 — Deepsy, May 22 '13 at 07:45
I'm just trying to understand the concept of prototype chain… — YON, May 22 '13 at 07:58

Khanh TO · Accepted Answer · 2013-05-22T08:08:16.803

0

I think the way to do this is:

  function Foo() {
         this.sth = null
// or this.sth = undefined;
    }

    var bar = new Foo();

Foo.prototype = null;: the bar.__proto__ will point directly to Object.prototype.
Without Foo.prototype = null;: the bar.__proto__ will point to Foo.prototype, and Foo.prototype.__proto__ points to Object.prototype

Another way:

function Foo() {
// sth...
}
Foo.prototype.sth = undefined;
//or Foo.prototype.sth = null;
var bar = new Foo();

edited May 22 '13 at 08:08

answered May 22 '13 at 07:49

Khanh TO

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It's just add a property to the object to preven Javascript to travel the prototype chain – YON May 22 '13 at 08:03
@YOnder: i think it's one of the ways. You may use Foo.prototype.sth undefined; – Khanh TO May 22 '13 at 08:11
Anyways, you have to override it by using its own properties or a nearer prototype properties. – Khanh TO May 22 '13 at 08:14
Got it. I can assign the null value for the bar.__proto__ – YON May 22 '13 at 08:59

score 0 · Answer 2 · answered May 22 '13 at 08:03

Actually, if you override Foo.prototype with null, the Foo's attributes will be deleted.

Foo.prototype.sth = 1;
bar = new Foo(); # Creates {sth:1}
Foo.prototype = null;
bar = new Foo(); # Creates {}

Take a look to the documentation page :

all objects inherit methods and properties from Object.prototype Object.prototype, although they may be overridden (except an Object with a null prototype, i.e. Object.create(null)).

Is there a way to hide Object.prototype's property?

2 Answers2