*adds another ampersand* H O L Y C R A P These videos make me feel like an absolute idiot in C++

The C++ series is definitely my favorite.

This is the MOST clear explanation of r- and l- values I've ever heard or read

Everybody: blown mind Cherno: bored so he has to fiddle with paprika

Hey Yan, just wanted to say that thanks to you I got a final 95 grade in Systems Programming course in my university (Computer Science BSc). Thanks a lot! I'm 100% sure that you have the best programming series. period. As a side note, no one EVER got me this excited to code and study :)

*My takeaways:* 1. lvalues vs rvalues 4:25 2. Main advantages 11:35 3. lvalues are variables with some kinds of storage backing them, rvalues are temporary values 12:25

lvalue has two components 1) value 2) address rvalue has only 1) value ----- rvalue is allowed only on right hand side on assignment only lvalue is allowed on left hand side of assignment lvalue is allowed on right hand side of assignment ----- On right hand side of assignment 1. As rvalue only has value, it's value is used 2. As lvalue has both value and address, what gets used depends on left hand side expression On left hand side of assignment 1. Only address part of lvalue is used 2. As rvalue doesn't have address, it cannot be used ----- rvalue reference is just an optimization hack.

The core explanation starts at 3:55.

I am not a programmer/software developer/coder. I'm not even sure I am referring to the right profession. I got here because I watched the reaction to unreal engine 5 and the ps5 (part 1). The way you explained things in those two videos got me hooked and now I'm watching a video on C++. I am a doctor and a lawyer and C++ is totally alien to me. But I found myself watching this video and "understanding" the main concepts you wanted to get across, which is a testament to how well you can grasp the important lessons and convey them to your audience. Made me want to study programming now (my wife would kill me). I went to a high school in the Philippines and back in 1982, it was one of the first high schools in my country which taught programming. We were taught how to program in "basic". A lot of my classmates became programmers and are now working in the US or have their own software companies. I went down a different path but if I had you as a teacher, who knows, I might now be working on dynamic global illumination and triangles, etc. You should try to fit in a teaching job in between your project development schedules. A lot of programmers/software developers/coders would benefit from your teaching and hopefully, someday come up with something special themselves. You would have the satisfaction of having a hand in shaping the minds of these future superstar developers.You can inspire them.

Digging the covid beard Also probably the most helpful channel I've found on youtube in regard to c++. If anyone ever asks me anything about this sort of programming this is straight where they're getting sent.

Woah, what a coincidence, I was just looking for a cohesive explanation of these yesterday! Great video, keep it up!

great job, I was looking for it a long time ago and after 1 month of research I finally got all of my answers, this is really good, I want you to explain it fully so other people can save their time :D Thanks a lot.

Been watching C++ series for a while. Great stuff. Just an aside, my compliments to you and your partner (if you have one with you) for the very nice home you have. Seeing various furniture, and now the kitchen, you obviously have good taste and done some wonderful things with your home. (see? Some folks DO notice more than just your skills as a C++ tutor 😉 )

Great explanation!! Thanks. - int& a; //lvalue reference - const int& a; //support both lvalue and rvalue(by temporary storage) reference - int&& a; //rvalue reference const reference in function for "temporary" rvalue, at 10:05. void Print(const std::string& name)

I'm learning C++ and immediately came across this syntax. The two books I have on C++ didn't explain rvalues/lvalues as well as you did with your examples. Thanks!

Chinese is my native language, I read an article in Chinese talking about the same topic and didn't understand. But now it's almost crystal clear to me thanks to this video! How do you remember these things if you're not using them every day? This is one of my biggest headaches about learning cpp

Yan! You rock! Even though this video was posted 4 years ago it is still relevant and to the point. There is still no resource on the whole internet who can explain it smoothly. Love the videos! You rock!

Awesome video Cherno! Been coding with modern C++ for a few months now, but can FINALLY say I understand rvalues and lvalues! :D

Clear to-the-point explanation. Your C++ series saves time googling a specific topic. Keep up the good work.

Thanks Cherno! I always wondered what the compiler was referring to in terms of l and r values. Had no idea it was actually a pretty simple concept. As always, thank you!

Thank you Cherno, your explanation why we use move semantics is so much better than what I have read from books. You have created a great playlist to understand C++ more.

Every tutorial you make is so informative and so well made. Thank you for making those videos free for all people.

Extremely well explained, calling lvalues 'location values' entirely cleared up the cloudiness about this subject for me! Amazing job!

I use L and R values all the time, have dealt with move semantics, etc. Clicked the link because I knew I always learn something new from you anyway. Did not disappoint. Excellent presentation of this material.

I've been waiting for this! Thank You! :)

Cherno, thank you so much! Your videos are awesome, and I can't wait for move semantics.

I read a lot of articles and watched many videos about it but no one explained it clear and short like this Thank you very much :D

Thank you for explaining this concept so well! Looking forward to your video on move semantics!

I know about that topic and advanced C++ concepts like move semantics already, but have to admit you do a pretty good job at explaining stuff like that to beginners. Great work. Hope you explain one day about why passing parameters by value and letting the compiler chose what to do might be good for performance. There’s so much to learn about C++, that’s why I like it.

Your videos are amazing ! Thank you for taking the time and effort to share your knowledge!

Thanks a lot for these C++ videos. They helped me out with a project at work that turned out great. I ported code from Python to C++ and saw a 10x speed improvement!

Thank you Cherno for all this Amazing content. I've learned so much with your C++ series 👍😎❤️.

This video answered so many questions that had been shelved in the back of my mind. Thank you.

I watched the ad of this videoon purpose bc you really deserve it :) thanks a lot for making this clear in my head!

You are seriously the only legit free video series for modern C++ Thanks a lot for partially sharing your knowledge for free!

Yan, you are a rock star! I just subscribed to your Patreon btw.. Look forward to all your knowledge about C++ and many other things too. Take care

I really hope you won't stop there as this whole topic seems to be quite hard to understand and you make such things appear really simple.

thanks cherno, i’ve always found this topic to be confusing, but you thankfully made it clearer

This has plagued me for long, and I've been programming in C++ (03) for years. Thank you!

This was the clearest and most concise explanation of this topic that I have seen. Cheers!

Man just following along with this makes things so much easier to understand in class. Thanks again Chrono, I also learned that he is an expert grind presser.

Thank you so much for your C++ videos! Love them!

Thanks Cherno, top quality content as always

Can't find the right words of praise for you. My deepest gratitude and appreciation!

Man, the video was great, it made lots of stuff more clear for me. Thank you for it!

Welcome Back Champ!! Thanks for the informative video on this topic,most of the online sites are quite confusing but you made it quite clear.Please post more videos on advanced C++ topics such as lambda function , constexpr , and new feature of C++ 17 and C++ 20....Also could you please suggest online materials for c++ that you refer usually? Thanks.STAY SAFE HOME!

Great explanation as always! Thanks for making these videos!

Definitely one of the best detailed explanation on l and r values in c++ Thanks!

If I remember correctly, then Titus Winter (or was it Herb Sutter?) gave a pretty good talk at CppCon some time in the past where he talked about all kind of value types. Very simply spoken, he just said: Everything that has a name is a lvalue, everything that doesn't is a rvalue. In detail it sure gets more complicated than that, but I found that explanation quite intuituve and maybe it helps somebody.

Thanks a lot Yan. This C++ series is really the best on KZfaq :)

Way more clear than the articles I've tried to read.. thanks a lot!!

Great explanation Mr. Черников Rly like your way of explaining things Thank you very much for the info and knowledge you provide : )

Explained beautifully! appreciate the clarity it provides

I love to listen when you talk about c++ don't stop pleas. This is gold.

For the love of god, please don't stop making videos. Btw , would like to see more on move semantics in c++. Thanks for the content.

I was so daunted by this going into it but your explanation was so good, thanks!

never heard this been explained so clear

Locator? Never heard of that. I always heard them as left-hand and right-hand values. Although as you point out they aren't always on the left or right of an equals. Then again I learned lvalue and rvalue in C first. Also really glad you decided to cover move semantics. I was left wanting after your smart pointer video. There's so much opportunity to talk about heap allocation ownership and tying lifetime to stack variables that can be moved.

Thank you so much! It was a really clean explanation and got all my questions answered :)

Perfect. Fantastic topic. This topic is very tied to move semantics as you already said. C++ is a great language because a programmer can manually do whatever he wants to reduce copying, manipulate with memory, do some optimization but if there is no awareness of that, using c++ has no much sense. It is like you want to clean your bathroom but with no special reason to do that. Good job!

Really appreciate the good work you're doing!

I'm actually learning c++ since 2 months now and this kind of Videos about c++ makes me happy that I decided to pick up c++ . I started with c and python because it was recommended everywhere but with python it was like owning a iPhone or working with windows. It's very simple to use and intuitive but you just don't feel satisfied. C++ is like switching to android or linux. You are overwhelmed by the freedom and possibilities and it just feels amazing to learn all the things and feel the power of that systems. I hope that makes sense.

Thanks for the video We are really looking forward to see your videos on design patterns 😇

C/C++ are my favorite programming languages. I love to learn new things about them and the way this clarifies lvalues and rvalues is absolutely fantastic, thanks a lot.

Dude you really have a gift for explaining stuff. C++ and opengl programming has become very easy for me thank you

Really enjoy your work @The Cherno

Thanks for making C++ so easy for me. Really appreciate all your hard work in it ^_^

There's something wrong in this explanation, and it's really easy to get wrong. I have to mention it here in case anyone get confused. *_Initialization is not assignment_* , though they share the equals sign... Assuming s is an std::string, when you do { std::string t = s; } that's *_initialization_* , calling the copy *_constructor_* std::string(const std::string&); when you do { std::string t; t = s; } that's *_assignment_* , calling the copy *_assignment operator_* std::string& operator=(const std::string&); You see, these two equals signs are calling different member functions, since they're inherently different operations. Although there should be no difference in the result, but first default construct an object an immediately reassign it is performance-wise not efficient. It's all the same when rvalue references are in the question, e.g. { std::string t = std::string("I'm a string"); } is calling the move *_constructor_* , std::string(std::string&&); on the other hand { std::string t; t = std::string("I'm a string"); } is calling the move *_assignment operator_* , std::string& operator=(std::string&&); Several videos titled "Back to Basics" in cppcon explain these basic C++ knowledge really clearly, so if anyone needs more detailed and thorough explanations please refer to those videos.

I love your demonstrations, it clarifies everything

I went from 0 to intermediate in C++ thanks to your C++ series. Keep it up! Thank you.

Thank you. Expecting to see a video on move semantics soon

loving your C++ videos hope to see more of it

Thank you so much, i've only started learning C++ recently and this is just what i need

The explanation can't be simpler than what Cherno mentioned. I am totally impressed.

*You just make it so simple. Thanks. BTW the large font used in IDE makes reading code easy to viewers. Nice.*

This was extremely helpful. I wish I found this video series earlier in my quarter, it would have helped me not bomb my first midterm lmao. Thanks to you though, there's still hope for my final. Thank you so much

Always clear, always good. Thanks

Thank you for clarifying this topic. Well done.

you nailed it man, please make more videos like this.

Thanks for sharing wonderful stuff Yan

one of the videos worth watching over and over again (and thanks so much for that double ampersand, for a whole year i thought it meant reference of a reference and that made me confused af xD)

I had forgotten about this topic, but you made it clear and quick.

Quick and direct to the point, really great.

Helps a lot!!. This is very clear explanation, especially the provided sample code example.

This C++ series is excellent. Thank you TheCherno!

This was a very clear explanation, thank you. I'm about to watch the move semantics video.

that just made me understand everything that I couldn't with c++ reference. you're a wizard. thanks

I was trying to understand this a year ago but left it there because too much information, this 10 minutes video made it crystal clear, thanks

Wow, I´ve had problems in my code, and I had no idea why it didn´t work, and noticed that it only worked on saved variables. Thanks to this, you´ve basically solved my problem, and can now edit it to make my some work. Thank you very much ^^

Best sum up about glvalues and prvalues I saw, nicely described what is going on and what consequences and benefits it brings. ♥

Great Explanation. Thanks for making it clear & stronger understanding

Wow this was very helpful & straight to the point ! thank you !

I am a big fan Just love the videos I love that you give a reason for everything

My God man. Watching C++ again brings back nightmares. Subbed!

Love your videos, at least until this one. I've been programming in C++ for about ten years, but I've never been so confused until now. I get the feeling that you think this topic is easy, and so you're blasting through your delivery in a seemingly nonchalant manner. This is because you're a freaking genius! This topic is ridiculously nuanced and complex, in my opinion. Can you recommend a source where I can learn the topic of lvalues and rvalues at an introductory level?

this is one thing I thought I'd never understand, but, as with most topics, you made it easy. thanks

Easily explained ... struggled to understand this two months back but when u illustrates it just seems like a peice of cake . 😁😁😁

Finally! Thank you for the video.

WOW. I definitely need to watch this 5 more times and take 3 sets of notes, this is actually really useful and ingenious.

Yeah!!! C++ series!!! Love that!^)