concepts-test.cpp

class A {
public:
	int add(const A &value) {
		return 0;
	}
};

class B {
public:
	int pridaj(const B &value) {
		return 0;
	}
};

template <typename T>
concept bool Addable = requires(T a) {
    {a.add(a)} -> int
} || requires(T a) {
    {a.pridaj(a)} -> int
};

int add(Addable a, Addable b) {
	return a.pridaj(b);
}


int main() {
	f(2, 2);
	B a, b;
	add(a, b);
}