C++ Newest Standard: C++20

C++20 is the newest standard of the C++ programming language, which was officially published in December 2020. It introduces many new features, enhancements, and improvements over the previous standards. Here is a brief summary of some key features in C++20.

Concepts: Concepts provide a way to specify constraints on template parameters, ensuring that they meet a specific set of requirements. This allows for better compile-time error messages and code readability.

Example:
```
template<typename T>
concept Printable = requires(T x) {
    {std::cout << x};
};

template<Printable T>
void print(const T& x) {
    std::cout << x << '\n';
}
```

Ranges: Ranges build on the iterator concept and provide a more usable and composable framework for dealing with sequences of values. They simplify the way algorithms can be applied to collections of data.

Example:

#include <iostream>
#include <vector>
#include <ranges>

int main() {
    std::vector<int> numbers{1, 2, 3, 4, 5};
    auto even_view = numbers | std::views::filter([](int n) { return n % 2 == 0; });

    for (int n : even_view) {
        std::cout << n << ' ';
    }
}

Coroutines: Coroutines offer a way to split complex, long-running functions into smaller, more manageable chunks, allowing them to be suspended and resumed at specific points.

Example:

#include <iostream>
#include <coroutine>

std::generator<int> generator() {
    for (int i = 0; i < 5; ++i)
        co_yield i;
}

int main() {
    for (int value : generator())
        std::cout << value << ' ';
}

Lambdas with template parameters: C++20 enables using auto as a lambda parameter, allowing for generic lambdas with templated parameters.

Example:
```
auto sum = [](auto a, auto b) {
    return a + b;
};

int res1 = sum(1, 2);           // int
double res2 = sum(1.0, 2.0);    // double
```

Constexpr enhancements: constexpr support is extended with additional features, such as constexpr dynamic allocations, constexpr try-catch blocks, and constexpr lambdas.

Example:

struct Point {
    constexpr Point(int x, int y): x_{x}, y_{y} {}
    int x_, y_;
};

constexpr auto create_points() {
    Point points[3]{};

    for (int i = 0; i < 3; ++i) {
        points[i] = Point{i, i * i};
    }

    return points;
}

constexpr auto points = create_points();

There are many other features in C++20, such as new standard library improvements, std::format, improvements to compile-time programming, and more. These are just a few highlights that showcase the versatility and power of the newest standard of C++.

2.8 KiB Raw Blame History

C++ Newest Standard: C++20

2.8 KiB

Raw Blame History