Closure practice

MDN Learn
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#1

I was practicing js closures for my understanding, Can any one help me in resolving the error “result is not a function”.
It would be of great help.
Below is the link:

#2

Hi @vaishnavi_A.N

Your function xy() doesn’t have a return value. You see that in your last console log where it states “undefined”. So you’re trying to call “undefined” like a function.

Cheers,
Michael

#3

Hello @mikoMK, I have corrected the code and thank you, but I have a question, despite writing the return statement, console.log(result) gives me undefined, why is it so?
Generally while storing the highest parent(outer most function) to a const “name”, and rendering that “name()”,why we are getting undefined?

#4

To create closures you need to return the inner functions. They will then keep the scope they had when declared:


var x = 2;
function xy(){
    const a = 2;
    console.log(a);
    console.log(x +=2);

    childFunction = function(){
        const s = 10;
        console.log('child',s+a);
        grandChildFunction=function(){
            const i = s*a;
            console.log('grandchild', i);
        }
        return grandChildFunction;
    }
    return childFunction;
}   

const result = xy();
console.log("res", result)
result(); /* childFunction() */
result()(); /* grandChildFunction() */
#5

@mikoMK
Ohh I didn’t know that.
I mean to access innermost function,we need to use ()()
Again as usual you are Amazing man @mikoMK​:+1::+1:

#6

I’m glad it was helpful. :slightly_smiling_face:
If you haven’t already I recommend reading the MDN article about closures:

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#7

:+1: :+1:
Thank you @mikoMK.
I haven’t gone through this previously, going through now.

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