How to Deal with Multiple Return Values in C++

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Gear I use:
-----------------

[TheCherno]

Hope you guys enjoyed the video! Just some quick notes: the code I wrote at around 10:30 needs some changes to actually work, since we've changed the type to a std::vector. Specifically, you could write either

std::vector<std::string> results(2);
results[0] = vs;
results[1] = fs;

or just

std::vector<std::string> results;
results.push_back(vs);
results.push_back(fs);

but leaving it as I left it wouldn't work, since we'd be writing to an index outside the array. Obviously in the video I'm just trying to get the point across about using an std::vector and not really trying to write complete working code, but just in case I thought I'd leave this comment.

[alguienmasraro]

For anyone reading recently, there's a better way with structured binding since c++17:

Return a tuple of your choice and return it as per the video:
std::tuple<std::string, std::string, int> getData() {
return { "One", "two", 3 };
}
Retrieve values using structured binding:
auto [str1, str2, number] = getData();

[nighma]

I think it will useful to keep these "optimization" parts in your video in the context you explain as a bonus for those (like you) who love it and try to create good optimized code. May be put them at the end of the video or display a little "sign" on the screen whe you speak about optimization if someone's complaining he's lost.

[panagiotispetridis]

at 13:20

It's worth noting that there are 2 more ways to make the code look somewhat better:

In C++11 you can use something like:
std::string vs, fs;
tie(vs, fs) = ParseShader("directory...") // tie() is in the <tuple> header

And in C++17 you can even do:
auto [vs, fs] = ParseShader("directory...")

also instead of creating 2 strings at the end you can just return make_pair(vs, fs);
or in C++17 return {vs, fs};

[Djzaamir]

i think structs and pass by reference methods are the best

[JackPunter]

I personally quite like <tuple>'s std::tie function, not sure what that is like for performance but is a good way to have 2 named return types (of any type) without having go and write a struct for every function that requires multiple return types.

[leixun]

*My takeaways:*
1. Tuples 10:49
2. Pair 14:00
3. Struct 14:30

[rv]

for tuple you can easily extract value like auto [vertexSource, fragmentSource]=func() in c++ 17

[RespecWamen]

I'm really glad you use the struct way. I'm a newcomer to c++, i used to program in Java and I solved this problem by making classes with just what variables i needed to return. I'm happy now

[homomorphic]

I return std::optional with a struct. Typically you need to be able to return a valid structure or "nothing" and std::optional facilitates that.

[DrAuraHxC]

I just want to say : C++17 Structured Bindings \o/

[tehLyrex]

I guess structured bindings take away most of the readability-concerns at least on the caller-side.
Returning something like a pointer to an array seems very odd to me and creates very bad habbits. That kind of usage can introduce very serious bugs, especially with inexperienced people. That's a thing I'd never recommend doing.

[simond]

Thank you so much for your indepth coverage of coding styles. As someone new to code you are making understanding c++ a very enjoyable experience.

Great Job Cherno!

[miteshsharma]

Now would be a really good time to make a video on templates, because people who know c++ templates are gonna get this, but otherwise Its must be like what's goin on man!!!!

[aubertducharmont]

A very nice video, explanation. I would like to mention that if you are precise, the function that takes non const reference as argument and return nothing is the most performance friendly.

[derivepi]

You can enumerate the tuple position value to make it somewhat readable - std::get<person(age)>(John) - John is the tuple and "enum person(age = 0, ...)" for the enumerator

[sander_bouwhuis]

Interesting... I came to the same conclusions as you a few years back when checking the c++11 specifications. Thanks for informing us about your views.

[manuelkoch]

the struct solution is definitely the best way to solve this for huge amount of variables and calling by references is the best for variabel num up to 3

[edenpanigel]

THE LAST OPEN-GL AND THIS EPISODE WAS VERY DIFFICULT FOR ME . JUST TO SAY THAT I FOLLOWED YOU FROM SCRATCH BUT THIS ONE WAS A LITTLE MIXED STUFF . I DIDN'T UNDERSTAND THE SYNTAX <GET> MAYBE ITS TEMPLATES...

[renade]

I agree with you, returning struct seems like the best way. I also like 1st two methods, passing references/pointers as inputs and making updates to them in function.
Other stuff you showed gets confusing quickly, mostly because I'm not that familiar with c++ library features. They keep adding new functionality I never seen before.