Time Stamps ----------- 2:46 - New Keywords 3:56 - Modules 9:03 - Ranges 15:00 - Coroutines 18:57 - Concepts 23:54 - Lambda Expression Changes 26:47 - constexpr Changes 27:54 - Concurrency Changes 33:33 - C++20 Synchronization Library 36:01 - Many more new features... 42:06 - Calendars & Timezones 45:27 - std::span 47:30 - Feature Testing Macros 48:36 - Version 49:12 - Immediate Functions - consteval 50:24 - constinit 51:19 - Class Enums and using Directive 52:07 - Text Formatting (std::format) 54:11 - Math Constants 54:31 - std::source_location 55:31 - [[nodiscard(reason)]] 55:51 - Bit Operations 56:34 - Small Standard Library Additions Thanks for that informative video!

Thank you very much, very informative! Now I have to go rewrite all the code I have ever written, wish me luck!

C++20 is like a new language

@YoloMonstaaa

3 жыл бұрын

no more headers and #include directives 🤯🤯

@FPChris

2 жыл бұрын

I personally never had issues before. int a = 5; has work just fine for DECADES.

Excellent talk! It really helps people like me get caught up with the latest developments in C++.

Marc Gregoire, thank you very much. Your book is one of the best in C++.

@marcgregoire

3 жыл бұрын

Thanks, I'm glad you like the book :)

@pablom2274

11 ай бұрын

@@marcgregoire I took the Cisco entry level c++ course and finished it, do you think I'm a good candidate for the "Professional C++, 5th edition" book? I'm also a fullstack developer with Javascript/Typescript. Thanks!!

Very clear introduction to the new features of C++20. Thanks

Excellent! Great overview towards c++20 finishing in one go!

Nice presentation. IMHO Modules and concepts are the most helpful features.

@CppCon

2 жыл бұрын

Glad you think so!

Thank you much. Your talk was very comprehensive to follow.

Nice summary, found a few things that will I start to use immediatly.

This is the language version of Christmas morning.

This was a fantastic overview of C++ 20. Thank you.

Very nice walk-through. Thanks a lot.

This is amazing, so much good stuff!

Thank you for this informative session.

Very useful overview about new features of c++20 with comparison c++17!! Great!!!

Thanks, an excellent overview of C++20!

seems like C++ is getting even more functional

Quite comprehensive! Thanks!

the speech is very informative. c++20 fabulous. i love it.

Great overview, thanks!

Great overview!

C++ 2O - C++ BORN Again ❤️

Nice to see Rusts Iterators coming to C++.

Thank you for this!

Great talk, thank you!

Excellent Talk!

Excellent

awesome !

Thanks, good talk.

Handful of new features in C++20 and eager to get my hands dirty and see how sweet/painful is it! Overall it was a long journey if we consider the whole transitions from late 90s.

good talk and good audio!!!!

very comprehensive

This could be one of the most important talks in this year's cppcon

constexprt strings, YES.

Good presentation of C++20. It has indeed many attractive new features (e.g. ranges; format; default comparison). Overall the C++ language still suffers from lack of standard libraries compared to e.g. .NET or JAVA; I hope they work on that in the future.

Haven't done much c++20 yet but I do love concepts. Quite similar to typeclasses in haskell

How does view::reverse work with infinite sequences like view::ints(10)?

@marcgregoire

3 жыл бұрын

first, view::ints(10) was wrong, it has to be "views::iota(10)". But, you better limit your sequence when using something like reverse, for example using views::take(...)

Can you please make a cheat sheet with a summary of all the new features? Thanks!

@marcgregoire

3 жыл бұрын

I think that would be a rather big sheet, as the C++20 update is quite massive.

So essentially C++ as some concepts from functional languages like F# and the pipeline processes of R? Nice really handy for Data Science task in larger datasets or streams where python or R are too slow and SQL is too limited 👍🏽

How to install C++ 20 on Red Hat Linux 8 ? I have installed the development tools on RHEL,. GCC and G++ also have been installed. How I can know if the version is C++ 20 ?

I took the Cisco entry level c++ course and finished it, do you think I'm a good candidate for the "Professional C++, 5th edition" book? I'm also a fullstack developer with Javascript/Typescript. Thanks!!

Is the coroutine example incorrect because it doesn't use `co_return` after the loop finishes?

@marcgregoire

3 жыл бұрын

No, the code is ok. It uses co_yield to return something to the caller. co_return is optional, if you don't need to return something at the end, you can just leave it out. Just like you don't need to write "return;" in normal function.

@monsterhunter445

2 жыл бұрын

Think of python iterators you just need the yield in the example

Does work on compilers happen at the same time as the standard is being decided?

@spauldoslady

2 жыл бұрын

Usually. There's generally several draft standards and item-specific documents that get published as part of the standardization process, and compiler vendors are often involved in the process anyway. Sometimes features are just standardizing common extensions the compiler vendors already offer, but I don't know how much of that applies to C++20.

@marcgregoire

2 жыл бұрын

Often yes.

So header Files are no longer needed to use anywhere or anytime?

@marcgregoire

3 жыл бұрын

Right, in new code, I would recommend to switch to using modules. It'll benefit your build throughput. But not all compilers are supporting it at the moment ...

It seems like the C++ standardization committee is trying to win over Javascript developers 😂

One day all code will be constexpr

Ranges looks somewhat similar to C# linq

Did they fix std::set so we can have non const iterators again?! It was deliberately broken in the past in case people change the key, preventing changes to any other part of the nodes data!!!🤪

With every release C++ is Approaching python semantics and syntax

Reminds me of Fortran.

If somebody knows about memory fences guarantees w.r.t. to synchronisation c++ primitives please let me know.

re ranges: Finally! We have cast off the shackles of C (or at least one of many), where the "stylish" way to iterate over something was to use a begin and end pointers. Yuck!

Who will use all of these???

Not a word about operator | for vector 15:00

54:55, how about a standard way of getting __PRETTY_FUNCTION__-like info ?

@marcgregoire

3 жыл бұрын

I'm not sure I understand what you want to do...

hi, please i start to leaern c++ for the first time, so i start with c++20, i got a book for it, but am having a big problem, i can't have a compiler for it, most of the IDE i use doesn't support the c-++20 features like (import), please i need your help because now i stopped the studying. i use these VSC extension codeblock embarcadero visual studio 2019 PLEASE HELP

@Abbatyya

3 жыл бұрын

please i need anyone help

@ABaumstumpf

3 жыл бұрын

How about not starting with the newest features that are not yet supported universally? Just use C++17/14 - they are widely supported.

@daniilgavrilikhin34

3 жыл бұрын

C++20 is now wastly supported (but not fully) by compilers.

@marcgregoire

3 жыл бұрын

The latest Visual Studio Preview has full support for c++20 modules.

49:33 - did you miss constexpr keyword instead of "const" on both slides?

@marcgregoire

3 жыл бұрын

No, if you make mm2 constexpr instead of const, then you'll get a compilation error. In my example I wanted to show that even though InchToMm() is marked as constexpr, that you are not guaranteed compile-time execution.

Is it only me who thinks that declaring variables like this makes it barely readable? auto var { int { 10 } };

at 25:00, what is mean by T x { } ?

@thorstenschimannek3866

3 жыл бұрын

You create an object named x of type T and use "uniform initialization" with the result depending on T. If T is a built in type then it will be uninitialized. If on the other hand it is a class, then the object is created using the default constructor.

@marcgregoire

3 жыл бұрын

That just declares a variable x of type T and zero-initializes it.

@vladalu9794

3 жыл бұрын

Default value for T (default ctor or default 0 for int, float, double...)

can I start c++20 without knowing c++???

Some good and some bad ideas here. My biggest issue is the growing complexity of C++ and having people understand your code when there are so many constructs in the language. Ranges make perfect sense for C++. Views make sense but using | for pipe-filter in addition to OR in other contexts is yet another opportunity for people to see code who hadn't seen that feature just get lost at what they are looking at. It's not necessary to have such features. We can already do filters as a sequence of function calls.

It's really annoying when they use the expression " Now with CXX you don't have to this, you can do this instead... " But why !😢

Thank Typescript for giving me better TypeC++20.

many of these ... topics.. ...ideas... ...concepts... so to say were already discussed in the circles of programming languages creators and of programmers in the last years... in fact I find the D programming language has already all the benefits of those and has ALREADY today for example a better implementation of the module mechanisms... only sad that it is not as visible as C++ ....

​the problem with source_location is that in a real logger you would expect to forward arguments to std::format.. but having arbitrary argument count is not possible with the last source_location param. nice summary tho, i enjoyed. Thanks!

@daniilgavrilikhin34

3 жыл бұрын

You still can forward it to std::format as it ignores unused args. Or you can provide a specialization (I think) that will do nothing.

It's a great lecture. Tho I don't really like computer science. It's all about keeping making new concepts and names for people to learn and make simple stuff more and more confusing to keep their job secured.

@Maciej-Komosinski

3 жыл бұрын

So you would like to keep developing computer science without making new concepts, or you accept making new concepts but you would like them to be left unnamed? I guess you have similar criticism for, say, medicine, chemistry, physics, etc.?

C++ 20 just clusters the c++ landscape. I just don't get it why the committee is constantly adding language features that have no impact on performance. I mean, no one comes to C++ for its "cool" language features.

C++ 23: pointers are removed, no data types- it's basically Python! That's my guess.🙄

@TheMR-777

2 жыл бұрын

Well, that's not gonna happen for sure. C++ borrows the idea based features from Higher Level Languages, but using Dynamic Type System like Python, will make it slow like Python :)

@gast128

16 күн бұрын

Is it going the other direction; i.e Python and JavaScript getting type annotations?.