Javascript Objects behaving differently?

Question

So far I believed objects in javascript if assigned to another variable were always by reference.

For e.g

var x = {
    key1: "key1",
    key2: "key2"
}

var y = x

So if I do something like y.key1= "modifiedKey1"

values of key1 in x witll change too. x.key1 = modifiedKey1

however, when I do this, y = null or y= "someRandomString"

There is NO change in x

x is not null, it remains the same object.

What exactly is happening?

`y` is still a normal variable you can reassign. Once you change `y`, it loses all references to `x`. Compare `changing y` with `changing something inside y`. It's not the same thing. — Shilly, Sep 27 '19 at 11:26

score 0 · Accepted Answer · answered Sep 27 '19 at 11:27

0

Because you do set the reference to null meaning you no longer point anywhere, it does not affect the object it pointed to.
Same with y = {"a" : 3} - x will not change because you did not change the object y and x pointed to but you change what object y points to.

answered Sep 27 '19 at 11:27

luk2302

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If you set y= "someString", there still won't be any change to x – ABGR Sep 27 '19 at 11:29
@RahulDwivedi have you read the second sentence in my answer? – luk2302 Sep 27 '19 at 11:30
My Bad. You're completely right. The link against the question indeed answers it and I do not mind this question to be deleted. – ABGR Sep 27 '19 at 11:52

Javascript Objects behaving differently?

1 Answers1