For people having trouble remembering the order in which const keyword is to be used, here's a quick tip. You have to read it backward, like the compiler does. For instance : -const int * A; ==> "A is a pointer to an int that is constant." (or, depending on how you prefer to write it) int const* A; ==> "A is a pointer to a const int" but both are the same as explained in the video. -int * const A; ==> "A is a const pointer to an int." -const int* const A; ==> "A is a const pointer to an int that is constant". EDIT : As mentionned by simo simo in the comments bellow, const int * A does not mean that A actually points to a const variable. It just means that the compiler will not allow you to modify the pointed value *through* A. for instance : int val = 10; int const * a = &val; *a = 30; //this will NOT compile, you're not allowed to modify "val" through "a". val = 30; //this will compile. Same with : int val = 10; int val2 = 30; const int * const A = &val; A = &val2; //will NOT compile : you can't modify what A points to. *A = 30; //will NOT compile : you can't modify val through A val = 30; //this will compile, val is not constant

More simply: a _const_ is like a: "if I modify this, please give an error calling me an idiot because I modified a _const_ ".

Your C++ vids are the best on youtube, don't stop ^^

The C in C++ stands for Cherno. I'm convinced.

"C++ man ... That's how it rolls.." HAAHAHAHAH

Bucky teaches the cpp fundamental level, you teach the advanced one. Brilliant guys on KZfaq

"Now let's put const everywhere"

I'm taking a upper division c++ class at uni with a really old professor who can't teach.... you're saving my life

Every programming language ever: let's create a "constant" array ... then change the values inside it :^)

Learned a few things, and this clarified my thinking on const greatly, so thank you, sir.

You saved my life cherno... I love your tutorials and I would love it even more if you make 2d game tutorials in c++.

Was really confused and this made it a whole bunch clearer, again your videos are straight to the point, and relatively easy to follow! Thanks!

These videos are addictive. I am coding for long time and know most of it, still watching this playlist is so refreshing. I feel like exploring every details of C++ all over again and play with it. Great job @TheCherno! Your Game Engine series is also another gem engine! Big thanks

Funny short story, demonstrating all acquired Cherno-skills: I went ahead and compiled the code showed on 2:53. I wanted to see *if I could force a change to the const MAX_AGE using the a pointer* . *The code:* _const int MAX_AGE = 90;_ _int* a = new int;_ _a = (int*)&MAX_AGE;_ _*a = 85;_ _std::cout

"const is basically sort of like a promise that you give, in which you promised that something will be constant, that is it's not going to change. However, it's just a promise and you can bypass that whole 'promise', and you can break your promise just like you can in real life." I came here to learn more about C++ but I get legit life lesson instead...

Gold! As a longtime hobbyist programmer who's new to C++, these videos are amazingly helpful.

Thank you so much for clearing up const's I really appreciate this series :D

Hey, I saw just two videos and clicked the sub button , your videos are really high quality and I left with a lot of answers than questions when I finish watching . Keep up the hard work . Cheers .

Thank you for all your videos! I just finished working through a C++ book, and I'm at the point where I try to make my first "thing," and I go "uh oh I still don't know anything." These videos are excellent for solidifying my understanding of things that I remember reading about, but do not yet have an instinct to know if I'm using them correctly yet in my own work.

Personal notes: - reading backwards helps understanding what is constant - making a class method constant says that that method will not change any of the class member - defining a function outside of the class and passing class instance as a constant reference makes sure that the instance won’t change. Thus, any method in that function must be const, otherwise you get error

You are so knowledgeable!! I don't know how I'd learn C++ without you!! 🙏🏻

Comprehensive and to the point. A great tutorial. Crystal clear. Thanks a lot for your effort.

You are the best!!! Really structured and easy to understand lessons!) Very useful for any kind of the projects) Thanks bro!

Man! I never understand this const properly. I learned everything I could find in books, lectures and other c & c++ videos on KZfaq. But this is the only video that solved all of my confusion on const. Thanks a lot man.

Thanks! The level of depth you go in is amazing!

Hey man, I've never seen these in-depth concepts before in my University! Many thanks for this!

This is how I see c++: const *int &int const ***const const *** &const

you are a reason I fell in love with c++ language again, your c++ videos are simply awesome :)

bro your channel is a gold mine i just started learning C++ also new to programming but your vids help alot. would love to see u do games like asteroids and snake etc with C++

You are the best one I found so far with a clear eng accent that is able to help me learn C++. No offense to other KZfaqrs with strong accents.

Really nice tutorial, I already know C++ and I just ran across this, but it still cleared a couple of things up, in terms of the mutable keyword at whatnot. I will probably keep watching these in case there is anything else I missed :) :)!!

Thank you for using a dark theme with your coding examples. It makes a massive difference.

You really did make me understand what const's are and how do they work, have been trying to find answer to it from so many websites and videos I can't believe I now understood it all. Really thank you so much!!

These kind of details will take us countless hours to grasp from reading a book (with omission often), this is amazing.

i have been searching c++ videos in several platforms for two weeks i think i have finally found a good one

Simple and clear explanation. Keep up the good work, friend 👍

You are seriously the best code teacher I've seen and I bought something like fifty udemy courses.. keep the good work and combining assembly and c++ together! Its great and im learning alot even as a long time java programmer! Thank you a lot!!!

What a clarity I found here :) Thank you soooooo much!

You have the best c++ tutorials in youtube dude

For people having trouble with the (const Entity& e), it's just that the function can't accept any instruction able to change the object (one of it's parameters) as you've set it const.

Fantastic video Cherno as usual, thank-you for uploading! What is your opinion on using const everywhere possible? I came across big flame war on StackOverflow recently between people that supported the 'security' and 'consistency' of using const wherever physically possible and those that said it was an eyesore. We're talking about using const literally everywhere - a simple 2 line function that takes in one integer to use in some quick calculation? It must take in a const int because the value is not modified. Would you say it is an eyesore to have it everywhere or do you think there is some benefit?

Thanks man ..... your tutorials are very clear to follow.✌️

03:28 "Now let's start adding const everywhere" - Cherno be like - let the games begin baby😂

Literally amazing video, just answered all my questions about const (and more) in 12 minutes, you're a GANGSTER

For anyone still struggling. A good way to read these statements is from right to left. Example: const int * (pointer to an int constant), int const * (pointer to a constant int), int * const (constant pointer to an int), const int* const (constant pointer to a constant integer)

Man, I start to think if I really should pledge through patreon to this series, because you are the correct one for me. INDEED.

Dude you are great!! you have really make the things very simple!!

Love your videos! So helpful. Could you bring back the suspenseful music though, it engages the audience making the videos even more exciting! Also, what happened to you mic from the first videos in this series (it sounds like you are recording with mono in a smaller room)?

dont forget that const makes a variable local to the file. that is, only visible in the actual translation unit. you can have 2 const variables with the same name in different files and it will compile fine. so basically they re implicitly static.

this video is the best const in C++ explanation till date i ever watched

As someone who's only approaching intermediate: Ahhhh.... Wait, holy. hell. what?!?.... Okay.. What.

Absolutely the clearest explanation of const out there!

are you ever gonna do function pointers?

im loving these videos, i am asking if you can make a video on friend functions

The best video on the const keyword, and it's not even close. Good stuff!

daym, so much to take care of when working with const stuff..

This channel is awesome!!! Thank you for sharing your knowledge :)

i am on the patreon and donated . i cant thank you enough. please carry on taking video in c++ :)😀 keep up the good work

te amo cherno acá te estamos viendo con un amigo muchas gracias!!!!

man o man you are awesome and most the programming i learnt is beacuse of you and buckey

I really like how he does sarcasm in the middle of a serious lesson ! But I guess that's how it rolls😂

dud, your knowledge exceeds the physical barrier of the realm

Thank you. Could you also introduce a little bit more about return constant, return reference and return constant with reference? I'm confused about these three things.

a great explanation thank you !!

Thanks! Refactored my whole program at work

"Haha, point out" That was comedy gold

Really helpful, thanks a lot

Thank you Yan for your tutorials! PS: now I can understand: const int* const Method(const int& const p1) const;

Well, I finally underatand! Thanks Cherno! Const has always confused me.

Great Video thanks - I learnt some new stuff here .

Thinking way back to my short time with C. Constant was a term used when using the preprocessor directive #define to name literal values. The purpose was similar to why you might use a named function rather than writeing inline statements(only need to write it or change it in one place), the question is why not simply assign the value to a variable name. The given reason was that it helped produce faster running and more compact machine code because the compiler must consider that variables are potentially ... variable and mutable at run time while constant literals don't change at run time and can be more easily handled by the compiler in the optimizing stage. Of course that book was from 1993, compiler optimizers have improved enough since that they can likely take up the slack if the programmer takes the easy route like declaring a variable when a constant literal value is the intent. And that was C89 not C++14

Love your videos, thank you so much!

This was such a good video!!! Multiple *holy shit* moments for me throughout the video. This is better than Breaking Bad ngl.

Easy to remember like this: * const -> pointer(*) is constant(const) const * -> constant(const) value at pointer(*)

One of the best teachers ever!!!

this is a complete video I was looking for thanks sir.

really good video !! I love it.!!

Amazing! Thanks a lot!

soooo helpful man thanks

*You the best.*

Thankgs for the great vid, I feel this is how I should have been taught programming. One question Cherno, how do you move around in your IDE ? Do you use the arrow keys, the mouse or some other bindings ?

Thanks for detail explanation. :)

Super helpful. Thank you!

Pretty clear, thank you. It should be noted, if a global variable is declared as "const" or a variable is declared "static const", then it is placed by the linker into a non writable CODE or CONST segment. When it is written to by some pointer trickery, an access violation exception will probably happen.

Fantastic, thank you!

Great video. Could you consider doing constexpr as well?

This is one of the more entertaining episodes :D

Awesome video. By the way which IDE you are using in this video??

I spent like 20 minutes and then looked you up🤯🤯🤯! Thanks

thanks for the effort

Thank you very much for your videos 👍 Very useful

const video* const Upload() const {} Cherno, please upload videos constantly and make it an immutable fact. :D

Superb!!

const bool confusion = true;

Can you make the video on how you type this fast in VS? Amazing content btw !

You should make some videos on specific Design Patterns, in particular (for me) the Strategy Pattern in C++. Maybe, recommend some books for learning the main Design Patterns every programmer should know ...

awesome explanation

Awesome video, you saved me

cant we also declare the variable in a private class? Will this give us same functionality? Thanks for the great videos!

Good explaination cherno sir