RXJS Operators Explained with Examples: switchMap, map + More

This is the second part of an RxJS tutorial for beginners who want to understand RxJS operators like switchMap, map, concatMap mergeMap and more.
Even while reading the RxJS documentation, the differences between RxJS operators like map and switchMap didn’t come easily. If you feel the same way I once felt while reading the definitions, it’s all just a little too abstract to pick up in one go.
This video offers a simple metaphor for thinking about RxJS, Observables and Operators. It also addresses common questions about frequently used RxJS operators like, “what is the difference between switchMap and map?”
To watch PART ONE, which describes Observables, check out:
How are Observables Different from Promises? | Beginner RXJS Lessons
• How are Observables Di...
REAL LIFE RXJS EXAMPLES from my own work:
• RXJS Real Examples - 1...
This is part of a series focused on developing apps with Angular. To learn whether Angular is a framework worth learning, watch this video:
Angular is BETTER than React and Vue under 3 CONDITIONS
• Angular is BETTER than...
OFFICIAL DOCUMENTATION
rxjs-dev.firebaseapp.com
My name is Ben and I am a software developer. I have iOS apps and a few web apps. (Every other web app is comparatively small and was developed using vanilla JavaScript.) If you'd like to see what I'm about or what I've done, check out the links below:
THE PERFECT BOARDGAME - A site for matching tabletop games with your unique preferences
theperfectboardgame.com
SOLUTIONS FOR X - My first published iOS apps
solutionsforx.com
NEVER BEN BETTER - My Blog
neverbenbetter.com
MY PATREON SITE:
www.patreon.com/neverbenbetter
MY GEAR
Sony ZV 1
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Fifine Condenser Recording Microphone (which was unplugged about halfway through this video: sorry!)
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[@neverbenbetter8225]

Originally, I was planning on going over examples in code, but I decided against it to keep the video shorter and keep the focus on vocabulary. I'm wondering whether making another video - one focused on code - would be helpful to anyone?

[@andredealbuquerque105]

For sure! The code would be interesting to get this as a view of how to go outside of the metaphor

[@neverbenbetter8225]

Thanks for the feedback. If you have any specific questions or if you were looking for something when you found this (and the last) video, let me know and I will try to incorporate your questions.

[@georgepagotelis]

In the end we need to code to put into practice

[@Asaloy]

Of course this would be helpful :)

[@vishay09]

Yes please at least basic examples for each scenario will be great help.

[@pouriadaki8586]

one of the best explanation of rxjs since I started to learn programming , thank you

[@hyukshin2387]

This is gold.. I was having hard time grasping what exactly some of these concepts are and with this.. all solved like magic. Thanks so much 🙏

[@landon.wilkins]

Sir, thank you for breaking this down. You made my morning.

[@HamzehExplains]

The best metaphor could be used in explaining different RxJs operators in such short amount of time! Well done!

[@giorgimerabishvili8194]

Definitely the best explanation I've ever seen! Absolutely amazing channel and keep up more Angular videos please

[@neverbenbetter8225]

Thank you. You know, the Angular videos haven’t got a lot of traction yet, which is disappointing for me, but maybe they just need more time to be noticed.

[@liang3163]

The first man I found to be able to clarify these related terminologies, liked and subscribled!

[@tonyx233]

this is incredibly well done, thank you for the series.

[@thegoodgolly1465]

I just stumbled on your videos yesterday and I have to say I really appreciate them! I've been a junior dev for about a year working in Angular mostly, and rxjs has always tripped me up. I usually just used the functions I notice that similar components use (mostly switchMap) without really getting what that actually MEANT, other than it took the data in so I could use it on the page. Sitting here having coffee before a meeting and listening to this has made a ton of difference and I plan on making visits to your channel a regular thing because you explain things REALLY well (the weather explanation is surprisingly perfect imo. There are so many moving pieces, like the meteorologist or the instruments they use, yet they all are relevant both in the example and in what they represent in the code). Thank you so much for this video and the other rxjs videos (and I'm sure I'll have more to thank you for in the future)

[@ameyakale3205]

I was just randomly looking to learn about Subject however I just watched the first part and was literally hooked. Really the best explanation I ever saw about the whole rxjs Observable

[@saianusha5979]

explaining with examples hits straight..loved it

[@ShanDev-be7qq]

The best analogy I have ever seen for the RxJs operators.

[@semperfiArs]

Best example of RXJS I have come across. Hats off

[@sweetnsourify]

Best explanation that I’ve heard. Thank you!! Will be checking out your other videos.

[@dianavlasenkova8957]

This is genius! So quick and clear! Thanks!

[@baluditor]

That was awesome explanation, thank you!

[@dilipshelake803]

Nice way to explain the complex things. Thank you so much..

[@RonaldJayBuayan]

best tutorial for beginners! you are amazing

[@huntermyers1046]

Excellent video. Starting with a metaphor is super helpful, and I wish more documents could be written this way. Once that framework is understood, the technical details are so much easier to contextualize.

[@DodaGarcia]

This was really impressive, subscribed

[@rembautimes8808]

This will make an excellent interview question. Thanks

[@craigiswayne]

This is great! thank you for your service. Using abstracted real life examples really helps, at least for people like me!

[@randomnamename1424]

Very helpful.Thank you

[@MohamedSayed-xl7gu]

awesome explaining !!

[@n2productions]

Ohhhh mannn... I've been racking my brain at work for days trying to get a handle of observables and RxJS to use for HTTP requests. This series is truly GOLD! THANK YOU SO MUCH, definitely a follow from me :)

[@neverbenbetter8225]

That is exactly how I felt when a I was trying to figure this out!

[@davidwildman4447]

I've been looking for something like this for months! First-time developer in my first job, and I've been struggling to understand observables from documentation and tutorial videos. This is what I needed - thank you!

[@neverbenbetter8225]

Awesome! Please, if you have any more questions, let me know.

[@anastasia3919]

Thank you very much for your work. It was very useful!

[@sandeepchandupatla7832]

Superb explanation, very easy to understand 👏

[@jorgen180]

Great example!

[@thimothelamoureux5718]

I love your explanations anx examples Ben. I think I'll have to watch this one a few times to really integrate the concepts with how I can use them

[@nikensss]

I really liked the way you explained both in Part 1 and 2!

[@neverbenbetter8225]

Thank you so much. If you are looking for more, I finally followed up with an examples video: kzbin.info/www/bejne/n6SsZ6Wmo7l8g6M

[@ItcomserveDe]

this was a great explanation :-)

[@imriharlev5151]

Thanks for the good explanation 😁

[@riccardomassafaidatech]

Really, really helpful

[@pbezanillat]

Nice video, very teaching

[@yarmab]

You are definitely good at the things explanation👏

[@alfred7010]

In one word amazing

[@ansaardollie7584]

Incredible explanations. Thanks for the insight

[@neverbenbetter8225]

I appreciate your comment! Thank you for watching!

[@parishare2750]

Bravo man! Thanks for this great explanation/examples. I will still have to brew a pot of coffee and listen to this 5 times but you definitely make far more sense than the documentation to me!

[@neverbenbetter8225]

Thank you so much! Glad I could help!

[@naimeahmed1192]

You know what, I couldn't stop login to comment and like and subscribe after watching your explanation. Thank you man. I just become a fan of you :)

[@neverbenbetter8225]

I really appreciate that!

[@rviswak21]

Excellent

[@ahmedouyahya]

GENIOUS!!!

[@mirandamoralez6354]

Enlightning!

[@kokoyroy]

U are awesome. U helped me to understand rxjs.thank u so much dude

[@neverbenbetter8225]

Thank you so much. If you have any questions, please let me know. These videos are picking up more attention lately so I’m motivated to produce more content.

[@nauristisanchins9306]

Very Helpful content, as rxjs is a very confusing when 'observing' the documentation alone! Thankyou!

[@neverbenbetter8225]

I’m so glad to hear this was useful!

[@ujuzitek301]

Fantastic

[@dhyeypatel7449]

you are awesome sir

[@duckhorse2563]

Thank you.

[@DotnetistEnterprise]

Nayshh thank you for this

[@ddomingo]

Great analogy! This helped me understand the difference between concatMap and mergeMap. I think it would be nice to mention that this analogy is perfect for hot observables, but doesn’t really apply to cold observables

[@neverbenbetter8225]

Great suggestion!

[@MG-wx8yx]

This video is 2 yrs old and I’m seeing it now!!!😔. I hope you doing well bro. Observables is the most difficult thing for me in Angular, but those operators are so useful.

[@SatyaRam2k14]

Why on earth, is this guy so underrated?????????????? WHY!!!!!!!!!!!!!!!!!!!!!

[@chrisfelix9065]

God bless you!

[@goosemoose1213]

ty

[@x11y22z33me]

Brilliant analogies. I am encountering rxjs and ngrx for the first time, and this helped my understanding a lot.

[@orleydoss3171]

Late to view... excellent explanation very easy to follow. Getting good base/foundation from this and other sources.

[@kjmoses8546]

I like literally everything u do .. And what microphone and camera name u use .. Just so i would one day have one..and i need ur suggestion .. Can i use them for short action movies

[@toddzmijewski6002]

What happens when combineLatest is used on the weather station but wind gauge never emits a value or fails to emit a value for a prolonged period of time. Are all the instrument values of the weather station required to analyze the weather or can the weather be analyzed based on a subset of instrument values from the weather station.

[@hamzakamel5635]

I loved your way in explain as a story but i think what is the better show some code example, Thanks.

[@vanukurunagesh9051]

Hey. It was a great explanation. One of the best in fact. But it would be more helpful if you could add coding example at the end of the video.

[@neverbenbetter8225]

Thank you so much. I just posted an example video that piggy-backs on this one: kzbin.info/www/bejne/n6SsZ6Wmo7l8g6M

[@ricko13]

I got way more confused, thanks

[@toddzmijewski6002]

The meteorologist combining insights from the source (weather station) would use a concatMap unless you want to cancel inflight insights and replace them. Furthermore, the withLatestFrom() operator has an observable as an argument. That operator does not provide access to the emitted value. It combines an emitted value with the another one from a separate, isolated observable that is an argument passed to withLatestFrom().

[@sandeepguntupalli8482]

💖 from India will be nice if you explain with codes too

[@kmui6022]

what i dont get about rxjs. it is often used for async calls. but why? unless it is not using websockets we can expect only one incoming response? isnt an observable complete overkill here? for these simple predictable http requests it seems that rxjs is too complex. can someone proof me wrong pls?

[@goldfishbrainjohn2462]

When will you come back to make another video? By the way, has anyone said you look like Robert Pattinson?

[@msettecasse]

I still don't understand the observables, it would be good if someone could explain with real cases how to apply them....

[@Asaloy]

I really like the sketches but there is also a little bit too much information in a very short time.

[@dylanhall5305]

Thanks for not using marbles

[@_grzehotnik]

useless tutorial if you don't show any code to present your examples as