C++20 Concurrency — Part 2: jthreads

by Gajendra Gulgulia

In this part of the issue, I’ll discuss about the new std::jthread that helps us avoid the boilerplate code for joining the conventional std::thread in the first section. In the end, I’ll also mention about the std::swap algorithm’s specialization introduced in C++20 to swap the underlying thread handles associated with std::jthread ...

20 Smaller yet Handy C++20 Features

by Bartlomiej Filipek

C++20 is huge and filled with lots of large features. Just to mention a few: Modules, Coroutines, Concepts, Ranges, Calendar & Timezone, Formatting library.

But, as you know, that’s not all.

Depending on how we count, C++20 brought around 80 Library features and 70 language changes, so there’s a lot to cover

In this article, I’ll show you 20 smaller C++20 things that are very handy and good to know. Ten language elements, and ten more for the Standard Library. Most of them with a cool example.

Let’s jump right into the text!

Improving Stability with Modern C++, Part 4 — Memory Management

by Ralph Kootker

When we started learning C++, we were all taught that every new needs a corresponding delete. But sometimes we'd forget, or some code might throw an exception we weren't ready for, and then we'd leak memory. [...] With rare exceptions, C++ programmers should not have to write new or delete ever again.

Design and evolution of constexpr in C++

by Evgeny Shulgin

The authors suffered greatly from the inability to use STL containers and wrote the std::vector and std::map analogues. Inside, these analogues have std::array that can work in constexpr. Proposal [P0784] Standard containers and constexpr studies the possibility of inputting STL containers in constexpr evaluations. Note. It's important to know what an allocator is. STL containers work with memory through it. What kind of an allocator — is specified through the tempte argument. If you want to get into the topic, read this article.

The Interesting Evolution of std::equal_range

by Jonathan Boccara

The good old std::equal_range STL algorithm, which has been in the STL since C++98, has evolved along with the versions of C++.

Starting from a poor interface and now a much better one, its story is an interesting example of how to improve the abstraction of an interface...

Little C++ Standard Library Utility: std::align

by Lesley Lai

Recently, I learned about std::align, which is one of the lesser-known functions in the C++ standard library because of its limited use cases. Since it is hard to describe without a specific use case, I will use a simple implementation of an arena allocator as a motivational example.

C++20 Concepts: Part 5 (Advanced use cases)

by Gajendra Gulgulia

In this article, I’ll explain and demonstrate how to define concepts that constrain multiple template parameters and more importantly how to use them in a generic function. As promised in the part 3 of the series, I’ll explain this using a function comparing for equality of two different types T and U

The Type-Traits Library: Correctness

by Rainer Grimm

The two main goals of the type-traits library are very convincing: correctness and optimization. Today, I write about correctness...

The Evolutions of Lambdas in C++14, C++17 and C++20

by Jonathan Boccara

Lambdas are one of the most popular features of Modern C++. Since their introduction in C++11, they’ve become ubiquitous in C++ code.

But since their appearance in C++11, they have evolved and gained significant features. Some of those features help write more expressive code, and since using lambdas is so common now, it is worth it to spend time learning what we can do with them.

Our goal here is to cover the major evolutions of lambdas, but not all the little details. A comprehensive coverage of lambdas would be more suited for a book than an article. If you want to dig more, I recommend Bartek’s book C++ Lambda Story, that will tell you everything.

The general evolution of lambdas is to give them able the capabilities of function objects manually defined.

This articles assumes you know the basics of lambdas in C++11. Let’s take it from C++14...

C++20 Concepts: part 4

by Gajendra Gulgulia

In this issue of the concepts tutorial, I’ll discuss in detail about abbreviated function template syntax , constraining auto with abbreviated function template syntax , constraining deduced return type, i.e. constraining the auto return type with concepts...