Methods may declared as friends as well as functions:
class Accesser {
public:
void private_accesser();
};
class PrivateHolder {
public:
PrivateHolder(int val) : private_value(val) {}
friend void Accesser::private_accesser();
private:
int private_value;
};
void Accesser::private_accesser() {
PrivateHolder ph(10);
// OK: this method is declares as friend.
std::cout << ph.private_value << std::endl;
}