What are some examples of constexpr in C++20?

What are some examples of constexpr in C++20?

C++20 introduced several enhancements to constexpr. For instance, you can now use dynamic memory allocation in constexpr functions.

Can you show me a simple example of a constexpr function?

Sure! Here's a simple example:

constexpr int square(int x) {
    return x * x;
}

This function can be evaluated at compile time.

What about using constexpr with classes?

You can define constexpr constructors in classes. For example:

class Point {
public:
    constexpr Point(int x, int y) : x_(x), y_(y) {}
private:
    int x_, y_;
};

This allows you to create Point objects at compile time.

Are there any limitations to using constexpr?

Yes, there are some limitations. For instance, you can't use certain types of dynamic memory allocation or exceptions in constexpr functions.