Javascript objects: get parent [duplicate]

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A nested object (child) inside another object (parent) cannot get data directly from its parent.

Have a look on this: 

var main = {
    name : "main object",
    child : {
        name : "child object"
    }
};

If you ask the main object what its child name is (main.child.name) you will get it.
Instead you cannot do it vice versa because the child doesn’t know who its parent is.
(You can get main.name but you won’t get main.child.parent.name).

By the way, a function could be useful to solve this clue.
Let’s extend the code above: 

var main = {
    name : "main object",
    child : {
        name : "child object"
    },
    init : function() {
        this.child.parent = this;
        delete this.init;
        return this;
    }
}.init();

Inside the init function you can get the parent object simply calling this.
So we define the parent property directly inside the child object.
Then (optionally) we can remove the init method.
Finally we give the main object back as output from the init function.

If you try to get main.child.parent.name now you will get it right.
It is a little bit tricky but it works fine.

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