How can I use friend functions in C++?

What are friend functions in C++?

Friend functions in C++ are functions that can access private and protected members of a class.

Can you give me an example of a friend function?

Sure! Here's a simple example:

class Box {
  private:
    int width;
  public:
    Box(int w) : width(w) {}
    friend void printWidth(Box b);
};

void printWidth(Box b) {
    std::cout << "Width: " << b.width;
}

What are the benefits of using friend functions?

Friend functions allow for better encapsulation and can simplify access to class members without needing to expose them.

Are there any downsides to using friend functions?

Yes, overusing friend functions can lead to tight coupling between classes and may violate encapsulation principles.