How To Use Iterators in JavaScript - Iterate Over Arrays and Collections

In this video I'll be showing you how to use and create iterators in JavaScript - you can use them to iterate over a collection or data structure.

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#javascript #web #development

[nikolajacques]

Not an easy topic. After struggling with it and making it out on the other side, it seems clear to me that a lot of thought was put into making this tutorial. Thanks!

[jevforsberg]

Fascinating and educational. Thanks for this!

[hansschenker]

finally understood Iterator! Thank's a lot for publishing!

[Shivs]

Thanks man, learned something new today

[ahora]

I'm first? Wow. Even though I know about iterators it's nice to listen!

[rashidsun]

Perfect explanation of not easy issue!

[bengbeng]

waw, your way of explaining things is very impressive, you make things easier, thank you. (by the way, are you from Africa because your accent sounds like one)

[kyleg]

Thanks for this. Can you explain what you mean when you say numbers[Symbol.iterator]() is the same as numbers["length"]()? Do you mean numbers[i]?

[jaisah]

Your keyboard made more noise then you😅
Btw nice explanation.

[guidoglielmi]

Is the iterator object a generator function?

[AleksandrStrizhevskiy]

I am getting an error: cannot read properties of undefined. I will just loop differently through the data structure but it is strange that in your video the system goes through the undefined value without a problem but I get an error.

[wagnerpedroo]

foi simples sua explicação, mas uma pergunta que tenho é: como posso usar o iterador na prática

[keepitplainsimple]

You explained it really nice
But I didn't get it completely 😅

[SMBLtheGamer]

I thought iterators were just the regular "for loops, apparently JavaScript finally has a for each loop like function.

[RebelMAC]

"so, you might be quite impressed with how it works, but also a bit curious..."....

No, I'm curious about WHY it exists. It seems like extra complexity and typing for going through a for loop? Why would I even use this???

[tamikuru]

I am SO confused about the last 2 minutes.

Why is it "new and not "new (<- there's a dot)
It's obviously not "new because we'd land inside the constructor then.
would work i guess, following the example at 3:50, but also only because numbers is an array and already has an iterator. Not because we made one for numList?

But doesn't that mean that numList.numbers['length'] works because length is a "hidden"(hidden to the for loop) value inside the array numbers. testable by:
Thus does NOT point inside the array "numbers" of the object "numList" but rather to the iterator inside the "class" to array.
Now something like const x = new array('a', 'b'); wouldn't work because an array is an inherrent data structure, doesn't need to be constructed and thus doesn't have a cunstructor i guess? But array should still be a class of javascript that stores all the methods like array.push()


I am confused because at 3:20 you said numbers[Symbol.iterator]() is no different to numbers['length']().
Now numbers['length']() wouldn't work anyways only numbers['length'] would... i think, didn't test.
The whole point is that numbers['length'] and numbers[Symbol.iterator]() are inherrently different because:
numbers['length'] points inside the array but
numbers[Symbol.iterator]() points inside the class dealing with arrays

[angelortega]

Hi, excuse me, do you have any video where they teach
how to import a csv file and display the data in an html table?
to then be stored in a database.
In java.
Greetings.

[mahamamjad]

You said "ITERATOR" and I heard "CINDERALLA".

[pencilpopart]

I deem this video completely unhelpful, because after 10 minutes I still didn't understand a word of it.

[mauricioperez]

why all code courses have this annoying keyboard click always so loud, it's a big distraction.