If we assume to just 'index' variable, it would also work! then why they use BackTick(`${}`) method? If you will to answer it?

Question

const arr = ['0', '1', '4', 'a', '9', 'c', '16'];
const my_obj = {
[Symbol.iterator] : function* (){
for(let index of arr) {
yield `${index}`; // if we assume to just 'index' variable then it would also work! then why they use BackTick method?
}
}
}

const all = [...my_obj]
.map(i => parseInt(i, 10))
.map(Math.sqrt)
.filter((i) => i < 5 )
.reduce((i, d) => i + d);
console.log(all)

Answer 1

Perhaps it was intentional to use string interpolation, to yield a string form of each element from <arr> rather than the actual element themselves.

Not sure the reason why, *probably* to prevent accidental modification to <arr> elements.

I guess you knew that - when an element of <arr> was an object - yielding the element means to yield it's reference.

And that, would make (intentional and/or unintentional) modification to the said element in <all> array, to also reflect in <arr> array (a speculative opinion - tested).

Such thing would not happen if the string form of the element was yielded instead of the actual element. Because in that case, none of the elements in <all> array refer to an element in <arr> array.

(Edited)

Answer 2

Ｒｏｓｈａａｎ thanks bro for your fabulous reply .. I think, I should go with the default code as on ES6 modules mentioned on.. anyway thanks again..

Answer 3

Ipang thanks.. yeah.. might be the reason as well!

Answer 4

Mirielle yeah! exactly, what I'm asking for!