Object.create(someObject) function does not inherit the properties

Question

When an object is created using Object.create(someObject) method the properties of the original method is not derived by the created method. How to make it derive the existing properties.?

> a = {}

> a.p1 = '8'; // add a property to object

> b = Object.create(a);

> b // b does not inherit the property p1.
{}

To reproduce the bug use the node console as shown below:

$ node
> a = {}
{}
> a.p1 = 2;
2
> b = Object.create(a);
{}
> b
{}
> a
{ p1: 2 }
>

You are incorrect; object b will inherit p1. I can prove it my browser console; maybe your syntax was incorrect when you tried this out? — Jimmy Breck-McKye
– Jimmy Breck-McKye, Commented Sep 6, 2014 at 20:33
$ node > a = {} {} > a.p1 = 2; 2 > b = Object.create(a); {} > b {} > a { p1: 2 } > — Talespin_Kit
– Talespin_Kit, Commented Sep 6, 2014 at 20:34

idmean · Accepted Answer · 2014-09-06 20:47:53Z

3

There's no bug all is working correctly. From MDN:

The Object.create() method creates a new object with the specified prototype object and properties.

The object is created with a prototype but prototypes are never shown in node (and in any browser console I know). You can see the prototype by using b.__proto__

enter image description here

edited Sep 6, 2014 at 20:47

answered Sep 6, 2014 at 20:42

idmean

15k9 gold badges63 silver badges90 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Talespin_Kit Over a year ago

Just curious. About like 5 minutes ago you had thought reproducing the problem was strange which means you were not aware of the answer. How did you manage to find the answer so fast.

idmean Over a year ago

@Talespin_Kit After trying it out in the node console I checked the MDN documentation to make sure I remembered correctly what Object.create does. And there I just realized that it creates an object from a prototype. So I tried displaying the prototype and indeed it worked.

lorefnon · Accepted Answer · 2014-09-06 20:41:25Z

3

Prototype properties will not be a part of string representation printed to console.

You can verify that b.p1 can indeed be called and the corresponding value is 2

You can also try printing b.__proto__ which gives { p1: 2 }

answered Sep 6, 2014 at 20:41

lorefnon

13.1k8 gold badges66 silver badges97 bronze badges

1 Comment

lorefnon Over a year ago

Yes. JSON.stringify does not serialize prototype properties - There is already a relevant SO question : stackoverflow.com/questions/12369543/… The accepted answer has links to ES specs.

Collectives™ on Stack Overflow

Object.create(someObject) function does not inherit the properties

2 Answers 2

2 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related