Mastering React Memo 

Jack, I think you should use "reference identity" instead of "referential integrity". The "referential integrity" is a term from a relational database theory and it is a guarantee that all references (foreign keys) point to existing entities and there are no "dangling" references/pointers in your database (or application state). For example, in a normalized Redux store it would mean that if a post object in a "posts" collection has a list of IDs of "comments" (a foreign key form "posts" to "comments"), then all comments referred by the post must be present in the "comments" collection in the store. In a normalized store posts do not keep direct references to comments, only IDs, so it becomes important to care about the referential integrity, as it does not happen naturally. The "reference identity" OTOH is just a special case of an equivalence relation, which guarantees equality of two referenced objects if and only if the references point to the same object ("shallow equality") but ignores structural equivalence ("deep equality"). React relies on the reference identity AKA "shallow equality" of two objects. It does not care about referential integrity, like lack of dangling references in your application state.

Great content Jack, thank you for taking the time to explaining React Memo so clearly.

These videos are gold Jack, it's hard to find such high quality and down to earth tutorials like these. Keep it up!

Recently discovered your channel and have found it extremely valuable! Liked and subscribed. You have a very clear way of explaining things that I have been struggling with for quite a while :D Thanks and hope your motivation stays high for creating more content!

These Mastering React Hooks series are really, but really helpful. I can't thank you enough for everything I'm learning from this. Keep it going!

Been looking at lots of videos and reading a lots of articles but couldn't get my head around when and on what these hooks must be used. And with this video everything is crystal clear. Was such a simple concept. Thanks Jack for this great video. Been following your a while for quality content.

I have seen dozens or even hundreds of youtube tutorials and this one is one of the best. Great content. I like most that the information is coherent, forming a whole. It is explained in detail. The pace and tone of Jack's voice are engaging. Fantastic job 👏👏👏

Your videos are always so clear, detailed and to the point. Every time I click on one of your videos and think I know about the subject, I always end up learning something new. Thank you for sharing your knowledge with us!

Hey Jack, just wanted to drop a quick message to say thanks for the video! I've been following your content for quite a while now, and I gotta say, you're hands down the best I've come across. I've learned so much from you, not just about coding but also your logical and concise explanations. Thanks again, really appreciate it!

This is the best video I have seen on the topic. From giving the concepts to telling its pros cons with correct usage. All things are included in depth summarized in this 27 min tutorial. Hope you channel grows

Amazing content as always , really can tell that this vids are professional because of how fluent you are with the syntax , the examples and the visuals of the video overall everything is very pleasing thank you

Very helpful video. Straight to the point, examples and comparisons included. Definitely cleared up a lot of my questions about React memoization. Thank you 🙏🏻

Fantastic explanation! Personally, I was struggling and confused about using memorization in React, but this video definitely helped me to understand this topic. Thanks Jack ❤

Thank you again! So clear explanation! That is the main difference between junior and senior-level developers - it`s when you can provide a clear explanation to your "team members".

Your explanation skills and demo demonstrations are so amazing! Great videos!

Really great explanation. Your videos are getting better and better! Thanks a lot!

Thank you! I really enjoy your content. Always concise and insightful! Great editing btw :)

The way explianed memoization comparing to traditional memorization was just amazing. in fact you just thought me how memizationreally works under the hood in react. the part where you mentioned when to or not to use moemo in react was also great example to understand the need for memo. thank you very much🙂

Thank you Jack ! I was looking forward to this. I am going to do few experiments for my own cases, but after that video, I feel better and less stressful about re-rendering I guess 😊

This is something really important that almost anybody takes the time to explain. Thank you so much and keep on this kind of amazing vids!

Thank you Jack! :) Every time I come to you channel I learn something new :)

From the moment you casually typed “zoom” as a css property (which I didn’t realise was even a thing), I knew this was going to be a good’un. Thank you, Jack. Wonderfully clear explanations. 🙏😎

Excellent breakdown, I think the part on renaming the function in your head is critical to understand this function for what it actually does. Really well edited video too, I'm looking forward to more from your channel!

Goddamn! Mm-mm-mm! You took them tutorials on the next level with these transitions and the chapter titles! Probably the best React/Typescript youtube channel out there. Thank you so much for the hard work, can't wait to see you have 500k+ subs on your channel.

The explanation about VDOM and DOM was amazing, I didn't know any of how that worked in React and I bet a lot of people don't as well. Thank you for your videos!

Thank you for this. I've been watching several videos from you, and they are all great. You go deep and into details, and throughout the way you teach a lot of small things that can help build the bigger picture. I'm interested to know about your career history, can you make a video about that? like when you started to program, what languages, frameworks, talk about the evolution of computer science from your aspect and so on... Cheers! (btw finally subscribed!)

"React Memo" == "Render if the props have changed"

The best and most thorough explanation I've ever seen! Fantastic!👍

This is really on a whole another class. Rich information yet so compact at a time. Thank you!!

Great video, Jack! Thank you so much for your work! Keep it going.

Loved your explanation. I subscribed immediately!!

The best tutorial on YT I've ever watched about the topic!

I had about a week of building an app using some components I didnt understand that seemed to require useCallback. I kept getting stale state from it. Now I understand why! Thank you much!!!!

Wow. These kind of videos i need learning react. I'm getting tired about all the crash courses(these are good for getting to know react)or full stack whatever and everybody talks about all the basics for begginers. Your videos are taking my understanding about react to a new level. Thank you. I hope you cover more and more advanced stuff because you explain them so well. Like a teacher.

I watched a lot of other docs and tutorials on those hooks and now finally I feel understand this properly, even if I used it many times already successfully now I get the fine details and differences and also when not to use them

Hi Jack, Extremely grateful for this insightful Mastering React series, a small correction at 18:30, I assume you meant to click on the Re-Render app button instead of the Change color button to demonstrate the memo failure with object type parameters.

wow the content is getting so much better ! great video !

Jack one of the best breakdowns I've seen on React Memo thank you very much!

I love the way you jump to code instead of wasting time on talking like others. Keep it up!

Thanks for this, my useMemo and virtual dom concept wasnt much clear before I watched this. Thanks.

Great explanation Jack! Thank you for your content!!

Thanks for the video! Comprehensive, straight forward and thorough. 🙏

Thank you for your amazing explanation! You made it so much clear to understand!

that transition at 0:45 is NICE.

Great stuff ! This topic was always confusing to me. Thanks !

Great Video. Thanks soo much. The whole react memo became very clear for me.

One of the best channels out there! Thank you

Found exactly what I've been looking for. Great explanation. Clear and easy to understand. Please do a series on advance react concepts

Thanks! Really nice and informative video, and again thanks for taking my suggestion :)

Thank you, your explanation way is so amazing and I learned a lot and how you use examples is great.

Hey Jack! I really appreciate the deep dives. Thank you!

I watched several videos on this channel, and I see all new videos ; To my surprise, I wasn't a subscriber to the channel yet!! 🙆🏾‍♂️, Subed now 🤓

By farrrrrrrrrrrrrrrrrrrrrrrrrr the best tutorial on those topic out there. Greate explanation! 👏

Excellent video as always ❤️

The best and detailed explanation on memo. Thank you so much.

Great content. You're a wonderful teacher. Keep up the good work, Sir.

Jack's discussion of "Don't Sweat Re-Renders Too Much", was eye opening. Thanks for explaining it in reference to old jQuery methods!

Great great video!! U explained the useMemo so well !!!

Hey! Jack, Thanks for explaining the memoization. This explanation really cleared the concept and usage well. Can you also create a video on redux-thunk vs redux-saga. That would be real great. Thanks again

Best explanation for memoization on RU-vid.

Extremely good explanations, thank you!

Great explanation! Was referring the official react doc but it wasn't as clear as this video!

awsome and comprehensive explanation thanks a lot

i liked the video before even watching.. I know it will be a great one 💯

Another great video! Thanks!

Jack, i have avoided using memoization in React for a long time. I've read blogs, watched tuts, without success. You're lesson here has just made everything click! Your preparation and relevant information are extremely valuable. Thank you very much.

This was purely informative, thank you so much.

you've got a new subscriber sr, you have the craft or art of teach good and clear

Jack, awesome videos like always, and great detailed explanation. One thing, just before your "5 Things To Remember" section, your video background tilts and slides away - At that moment I looked away and from the corner of my eye it looked like my screen was falling off my desk! Hahahaha, I got a fright there for a split second! 🤣

Awesome, subscribed!

Always great videos

Jack you are an amazing teacher! Thank you for this video!

Thanks, this was the best explanation I've ever heard.

Thanks mate, perfect explanation!

Hey, thank you for this awesome video! Really good explanation :)

best explanations ever I love your way for teaching.

Great stuff Jack!

Amazing job!!! I hope u will get that Silver Play Button soon. Big like!

Great video. Subscribed!

You can tell right away by his thinking out loud, that he is a senior developer xD. Thank you for your amazing content :)

8:51 ""it compares the previous props with new props. And when those props have changed it re-renders. Thats all memorization is. "". Missed that in an interview :')

This is GOLD ! Thank you.

Thank you for the masterclass on these topics

Awesome content Jack! Me once again with the questions. Would you share how you set up you VS Code in a vid?

Thank you so much, Mr. Herrington. It is really informative and well explained.

Perfect video. So helpful. Btw.. which extension do you use for code completion ?

best explanation with example. Thankyou

JACK your way of teaching makes you the best teacher i have ever seen .I am super impressed by the MFE video you explained .may i know what is that extension which is showing function output immediately

Thanks so much....this is a great video. I learnt alot 💯😍

This was such a clear explaination!

Thanks, what an incredible explanation ❤

very detailed and clear explanation 👍

Great content Jack, thank you!.

Hi Jack, great work as always! I have a question - should we always wrap our functions in useCallback if we pass them down as props? Because you mentioned that it is a good idea to wrap arrays and objects, which we create, in useMemo and I wonder if the same applies to functions.

Great video, again!!!

Thank you, Jack. I learned a lot 😊

Thanks Jack, for the awesome video

best video on this subject thanks for helping me understand this better

Great video. Subbed

Awesome, thanks jack!!