Unlocking the Language’s Latest Features, Enhancements

C++ continues to evolve, and as it does, its developers aim to balance its legacy of performance and control with modern features aimed at improving the security of C++ code and developer productivity. In its latest iteration — C++ 23 — the language delivers a wealth of enhancements and new features to cater to both seasoned developers and newcomers alike.

This article explores the key updates to C++ 23 and examines how they will undoubtedly impact the way C++ developers write and maintain their code in the coming years.

Overview of C++ 23

C++ 23 builds upon the foundations laid by its predecessor iterations, particularly C++ 20, which introduced major advancements such as concepts, ranges, and coroutines. The focus of C++ 23 is incremental improvements. It fills in the gaps left by earlier versions and adds features that improve convenience.

C++ 23 provides:

C++ continues its modernization journey while preserving its core strengths, which have made it famous.

Key Features and Enhancements

Key C++ 23 features and enhancements include the following:

Deducing This

Deducing this is one of the most anticipated new features in C++ 23. It simplifies the way member functions are defined and used in generic code.

It allows member functions to deduce the type of the object that they are invoked on, thus enabling more flexible and reusable code.

The impact: Deducing this improves the expressiveness of member functions, particularly in scenarios involving chaining or generic programming.

Here is an example of deducing this in a function that provides a way to change the x-coordinate of a Point object:

struct Point {
       auto setX(int x) -> Point& {
             this->x = x;
             return *this;

       }
       private:
                 int x;
};

The code above does the following:

The GitHub Gist is available here.

Figure 1. Deducing this in action in Visual Studio 2022.

if consteval Statement

This new type of control flow statement refines compile-time programming by allowing developers to write code that behaves differently depending on whether it is evaluated at compile-time.

The main benefit of using if consteval is that it enhances the versatility of constexpr functions and improves the clarity of the code when mixing compile-time and runtime logic.

Here’s an example of if consteval in use in a simple function:

constexpr int compute(int x) {
    if consteval {
        return x * 2; // Compile-time logic
    }
    else {
        return x + 2; // Runtime logic
    }
}

The above code does the following:

GitHub GIST is available here.

Figure 2. if consteval being used in a simple function in Visual Studio 2022.

Standard Library Improvements

The C++ standard library introduces several enhancements to make coding tasks easier.

Some updates extend the capabilities of the ranges library, including additional views and algorithms.

An update to the stacktrace library provides access to call stack information, which is helpful for debugging and logging.

A new feature, std::expected, simplifies error handling by representing a value or an error without relying on exceptions.

Multithreading and Concurrency Enhancements

In the latest iteration of C++, multithreading and concurrency enhancements aim to improve performance and developer productivity by introducing new features and refining existing ones.

Atomics with std::atomic_ref

The new std::atomic_ref allows for atomic operations on non-atomic variables, providing more flexibility in concurrent programming.

#include 
#include 

int main()
{
  int shared_data = 0;
    std::atomic_ref atomic_shared_data(shared_data);
    atomic_shared_data.fetch_add(1);
}

The above code illustrates the following:

Figure 3. std::atomic_ref in action.

Better Support for Parallel Algorithms

C++ 23 expands upon the capabilities of parallel algorithms, making it easier to write efficient, concurrent code.

Improved UTF-8 Support

C++ 23 embraces modern character encoding standards by introducing native UTF-8 support in the form of new string types and functions. The benefits of this are:

#include 
#include 

int main()
{
    std::u8string text = u8"Hello, UTF-8 World!";

    // Convert std::u8string to std::string for output
    std::string converted_text(text.begin(), text.end());

    std::cout << converted_text << std::endl;

    return 0;
}

Simplified Syntax and Usability Features

C++23 includes improvements in syntax and usability features, including the expanded use of constexpr in the standard library, which means more compile-time computation is possible.

constexpr for More Standard Library Functions

std::accumulate has been improved to be constexpr, meaning we can now use it directly in constexpr contexts instead of relying on a workaround like a lambda function.

The following example illustrates this:

#include 
#include   // For std::accumulate
#include     // For std::array

int main()
{
    constexpr std::array arr = { 1, 2, 3, 4, 5 }; // Define the array
    constexpr int sum = std::accumulate(arr.begin(), arr.end(), 0); // Compute sum at compile time

    std::cout << "Sum: " << sum << std::endl; // Print the sum

    return 0;
}

GitHub GIST is available here.

Better constexpr Support for Containers and Cleaning Up Syntax

Containers like std::vector and std::string now have improved support for constexpr operations, enabling more compile-time use cases.

There have also been changes regarding streamlining syntax, improving readability and reducing boilerplate code.

Benefits and Challenges

The benefits of the latest iteration of C++ include:

However, C++23 also comes with challenges:

Final Thoughts and Takeaway

The latest iteration of C++ represents an exciting evolution of the programming language. It offers powerful tools for modern software development while maintaining its legacy strengths and backward compatibility.

Whether you’re a systems programmer, red-teamer, game developer, or working on machine learning projects, C++ 23 equips you with some great new tools to write more efficient, expressive, and maintainable code.

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