The Power of JS Generators by Anjana Vakil

Generators have been around in JavaScript since ES2015, yet remain largely ignored by many JS devs, who don’t see why or how they’d use them in their day-to-day work. But generators - which we can think of as special functions whose execution can be “paused” and resumed later on - are actually extremely powerful tools for producing and consuming series of data. That makes them perfect for implementing lazy sequences, custom iterables, animation, even the convenient asynchronous programming we now enjoy with “await”! In this talk we’ll dive into how JS generators work, what makes them so powerful, and why you should care.
jsconfbp.com/speakers/anjana-...
About Anjana:
Anjana suffers from a chronic case of curiosity, which led her from philosophy to English teaching to computational linguistics to software development. These days she mostly codes & teaches from her home base in San Francisco, but she’ll always be a traveler at heart. Nerd out with her about functional programming & JavaScript, ask her about the Recurse Center & Outreachy, and definitely invite her to your karaoke party!

[@ilearnedtoday6014]

she is back

[@tikendying]

Folks been waiting for her like a star wars trilogy

[@Hunt92]

Exactly my thought every time i see her in a video

[@miloslazic3636]

@@bradyfractal6653 She is just excited and happy to be presenting.

[@EddyVinck]

I knew I recognised her from the Functional Programming talk I saw years ago! It's one of the first talks I ever saw and it drove me to learn more JS! Go Anjana!

[@mohammedsalah4954]

same thing here bro she is amazing 🔥🔥

[@kishanc8697]

Same here

[@jacobyoung2045]

Yay! One more Anjana talk on the internet.

[@2000mipo]

THAT TALK WAS SO GOOD RIGHT?!

[@carlospedroza2604]

She has given several awesome talks, and you can find multiple of them here in youtube! Search for her name, the subjects she covers are varied.

[@Play_Streams]

I love her energy. Great presentation too! I've always struggled understanding generators.

[@samuelmorkbednarzkepler]

Bro got that Einstein e=mc2 rizz 👀

[@neonsamurai]

Very good intro. And yes you're totally right, generators are underused. Very much appreciate your talk!

[@damians.7859]

Such a nice talk, it's a shame that the person that editted it made a lot of cuts when code was presented and instead showed audience from the back...

[@user-vj3cu3wv9l]

idk what are u talking about

[@4ipon4ik]

@@user-vj3cu3wv9l approx. 20:15 - 22:30 she explains her code step by step, but we don't see it because it's zoomed out.

[@user-vj3cu3wv9l]

@@4ipon4ik anyway u can't learn js by watching conferences

[@4ipon4ik]

@@user-vj3cu3wv9l idk what are u talking about

[@rishabhkalra9505]

Finally we have a great explanation to generators. I knew about these for quite some time but since they are not much used, had limited knowledge on how to make them work with complex things, especially async ones. Great session.

[@griof]

Another excellent talk. I'd recommend a talk she has about functional programming. She is a super good communicator!

[@stannone7272]

start at 9:18

[@ShubhamKumar305]

I've read about the iterators and iterables from MDN and since then I was like, now I know what can be iterated on JS and how. And when I read about generators I was like, yeah they are there, but how to effectively use them. Thank you Anjana for showing us the various ways.

[@alex_chugaev]

It was so exciting it ended in a blink of an eye. Thanks Anjana, generators have big potential. I’m gonna experiment with them, doing state manager and renderer.

[@phoneix24886]

Anjana is very energetic which makes the presentation interesting!

[@dianyuanda3383]

I've never seen any speaker in a tech conference that talk so enthusiastic like her

[@khushalbhardwaj6192]

just fascinated how can something that's so under talked and underrated small little thing can be this powerful and cool.

[@oleanddro]

Excellent presentation of GENERATORS! (who saw the introduction will understand) Great energy of Anjana Vakil! Thanks!

[@adittttya]

Amazing stuff! One of the best talks ever! 🙌

[@stevekyhon]

Watched from the beginning to the end. Good stuff!

[@VKD007]

I studied generators few years ago but this explanation is so fun man

[@hello2131991]

Her energy is unmatched

awesome Anjana Vakil, thanks for this masterclass

[@rollandbryan9908]

Brilliant talk. Please keep the code being talked about on the screen!

[@meljones2922]

Yup! Here's the code/slides observablehq.com/@anjana/the-power-of-js-generators

[@bmehder]

Anjana's talks are always bangers.

[@orangeprogrammer]

Thank you for speaking in this video. I have never heard of generators but now I am curious. Thank you.

[@chhavimanichoubey9437]

I can't believe that this video helped me understand generators better than anything I ever saw or read on generators.

[@ZiedHF]

Love her energy, what a beautiful soul. Thanks for this wonderful presentation!

[@kevinrobertandrews]

Taking from infinite sequences absolutely blew my mind! Thanks for sharing 😊

[@mahmoudaldawleh1982]

i love her energy😃

[@hyperrealhank]

This could be among my favorite conference talks

[@shegsdev]

Big fan of Anjana. Good to see her again.

[@Thanadit231]

love her power

[@angelbates5672]

Wow, this is such a great video. Thanks so much!

[@rojonali3374]

Definitely she is amazing 😊

[@user-dk5uv1xy5j]

We want more conf with her !

[@Glibenko]

I really appreciate your performance. Now I know more about generators and wanna apply them.😎

[@zokizuan]

Thanks Anjali for showering us with your...

[@oleksandrvorovchenko8674]

Great presentation! Thanks!

[@typescript_evangelist]

One of the best speakers.

[@moosesnWoop]

Great to see Anjana again, wow.

[@phanCAbe]

This is a great talk! However I always think back to the JS platform docs at my second job (at a very large company).... " Generators: Don't use generators." And it still makes sense because no matter what you do you'll always end up with code that's "too clever".

[@schobihh2703]

thanks!

[@anikets4699]

😂🤣😅

[@jincyquones]

"too clever" a.k.a. requires prerequisite knowledge of how they work, which most devs lack because they're too scared to use them

[@RamkrishanYT]

Bruh how is this too clever? It literally is explained in a 30 minute talk

[@McQuinTrix]

+1

[@taz2392]

I have no idea what she’s talking about but it looks cool

[@phytonprogrammer1998]

Happy to see you again 💜💜

[@code_react]

No doubt its very useful but Why would you switch camera while she is explaining the code 20:15. :(

[@alvarobyrne]

yeah, producer was sleeping or editor mistake, or what?

[@pavelmikhadiuzk310]

she is crazy)) and Is it contagious) It spreads) I even see how I shout "Generators!" in the middle of night while I am sleeping

[@TheLexuguin]

You've been using them without even knowing it. Async/Await are basically syntactic sugar for generators. Before them, to achieve a similar functionality, you had to use generators.

[@sayeednazir8884]

wovvv ,,,,,, really amazing....!

[@amarwavare711]

She made generators quite simple to understand !

[@soltsdev]

legend is back

[@KresnaPermana]

Finally the legendary is showing up

[@Rollmops94]

I looked for this for ages

[@savi_sandbox]

is there a way to download the slides, presented in the video?

[@sankaraishema5963]

Awesome I finally understand ;)

[@sandro6103]

She is fire 🔥

[@mohammedkaif1236]

AWESOME

[@Hoppi1001]

Would it be possible to get those code snippets from somewhere? Yes, I can copy from the screen but maybe I can save some typing if it is.

[@soumen_pradhan]

observablehq.com/@anjana/the-power-of-js-generators

[@omgd00d]

observablehq.com/@anjana/the-power-of-js-generators

[@anastasiiasolop6653]

the link was on the screen in the beginning observablehq.com/@anjana/the-power-of-js-generators

[@rdil]

The slideshow is linked at the beginning of the talk.

[@user-df1gs1kf8w]

Get a mac

[@spiral5799]

She is amazing, fun, smart, and beautiful

[@mknijnenberg85]

What is the tool/website called where Anjana makes her code blocks with?

[@sudheerpoojary8975]

nice explanation

[@kishorrathva4097]

How does event loop handles it?

[@misterl8129]

Anyone make the Starwars example work? I cant. How it is working? How i can console.log the object starwars with all the data? Thanks

[@vladislavpeev5822]

Quality content, but I needed to slow down the video speed a little :D

[@xeoneraldo1254]

Really cool technology, great to finally have it in JS. We already have that in C# for years, its nothing new. I wonder when will source generators come for JS.

[@AvanaVana]

I thought I understood generators. This blew my mind.

[@vytenisurbonavicius9593]

Great presentation and great energy! Regarding generators - it might be just me but it still feels to me like generators are a cool yet much less readable way to do stuff. Yield makes code run in a non-linear and less intuitive fashion. I wonder if it is just me...

[@michalkotlicki4710]

She becomes more energetic every time she takes a sip of this "water".

[@prigithjoseph7018]

Still need to be explain, what is the easiest way of implementing data science and Machine learning with js, and to more often a offline ide for such purpose.

[@ravierkonan1694]

Knew Anjana from her talk on Functional Programming. On her way to be the public voice of JavaScript.

[@uubaidullah]

og is back ❤️

[@SachinDolta]

Welcome back Anjana

[@qodesmith520]

At 2:38 she says "duck-duck-go'ing them..." #BOSS

[@mohammedkaif1236]

awesome

[@Rene-tu3fc]

not sure if python stole from js or the other way around, but they seem to look and function identically. very fun to use, but easy to create unreasonable code imo.

[@limitless9483]

great talk btw you guys could have at least linked up the resources from the end of the video to your descriptiopn

[@pahrurozi]

What is music intro?

[@espectropolitico]

You're like an Marvel Superhero, but to JS. Trully saved me a day (again).

[@iliyaskhan3803]

Anjana knows the best way to engage all your senses

[@samuellawrentz]

Great talk! Love how generators can be used for various usecases. Also lowkey, I'm getting Zendaya vibes.

[@softwarelivre2389]

What is Zendaya? Now I'm curious

[@farhanbajwa4954]

So one of the most important things generator does is that you cannot store an infinite amount of data on your memory like calculating factorials, or stream of data through api it look something like pagination only bring that part of data, when it actually needed.

[@SamruddhaShah]

Like your energy

[@yoni532s9M5w]

Why isn't js pressed about using generators for iteration like c# is? Isn't enumeration of entire arrays really bad in general?

[@fabiovictorino350]

Good to see you.

[@mdistiakhossain1035]

She is back again

[@hajiamano22]

Generators are so underutilized. I created a javascript framework with them that let's me build web apps in 1/10th of the time it took me before.

[@Ty-13]

Is it open source?

[@hajiamano22]

@@Ty-13 Not currently, and there are a lot of reasons for that. One there are a lot of better frameworks out there more suited for speed that people should consider like solidjs. My framework is different. It doesn't have custom components, just pre-built components that all fit together in a grid system. The cool thing is getting data from the user happens synchronously. So you don't need to have call back functions for forms. When it's on the screen the program yields and waits for the form to be submitted before continuing execution

[@stacksagar]

❤️❤️🔥

[@amansaxena4827]

👍

[@rahulkanyal]

Her energy and enthusiasm is mind-blowing.

[@nitsanbh]

Good code is clear, not tricky. Implementing a bidirectional channel using a proper object would be so much more readable (and customizable) than using generators’ .next tricks

[@chhiringtamang7875]

HOT NEW FEATURE FROM 6 YEARS AGO 🤣 BTW loved it.

[@mzubair10]

I didn't realize generators were so powerful

[@nhieljeff2156]

this is straight up sorcery

[@officialrajdeepsingh]

wooo

[@SuperQuwertz]

21:30 I want to see the code...

[@user-vj3cu3wv9l]

i'm not sure why do we need to use them

[@dc22199x]

Looks similar to php's generator, but basically this is mostly borrowed concept of disappearing pointers.

[@Tony-dp1rl]

Makes you wonder why they can't get Tail Recursion into JavaScript compilers, if they can do this stuff :/

[@ihatethesensors]

I'm watching this right now with the console open. Haha!

[@MartinCharles]

generators are sick

[@microcodes6887]

If you shows on the screen that's how it will execute then it will much better

[@farhanbajwa4954]

I learned generators in python and it looks the same in javascript.

[@workout.trending]

can anyone tell me how to learn javascript as fast as possible

[@mikoaj1954]

don't fixate on learning as quickly as possible, this is wrong approach. Just write your own code, bc that's the only way to get better at solving problems with help of programming language of ur choice.

[@madcalm2024]

Only in practice on complex projects with many real-life featutes.

[@workout.trending]

@@mikoaj1954 true thanks man

[@mehdi-vl5nn]

The problem with those who lack computer education is exactly this. The order is actually like this: Stackless coroutines, event loops, self-suspending functions, iterators, simpler syntax generators, coroutines with simpler syntax, async functions, tasks, promises or futures. But wait, my dear friends. Promises in JavaScript have nothing to do with promises in reality. They are actually a function that puts itself in a queue! JavaScript's foolish features insult the spirit of programming and computer science.

[@henrikrinne3639]

I like her