Question

Lets say you have this object:

mainObj = {
   foo1: 'bar1',
   foo2: 'bar2',
   foo3: 'bar3'
}

Now I want to make a close of this object by doing cloneObj = mainOb. Now we have two identical objects.

When I change the value of mainObj.foo1 = 'lolcats' after I made the clone then for some reason cloneObj.foo1 = 'lolcats'

I tested this in Chrome’s console on a much more complex object. I know for certain that there’s nothing in my script that would keep making the two objects sync up. I even made sure of this by creating random names for the cloneObj.

Is this behavior done on purpose or am I experiencing some sort of bug? Or am I just missing something very fundamental here?

Answer 1

You didn’t clone the initial object when you just did cloneObj = mainOb, you are actually passing a reference to mainOb that can be accessed via the cloneObj variable name. You therefore have two variable names referencing the SAME object.