How to accept the address of an overloaded statement defined as a friend in a body class in C ++

Question

How can I get the address of an overloaded statement defined as a friend in a class cube?

I tried the following

struct S {
  friend bool operator==(S, S) { return true; }
};

int main() {
  bool (*f)(S, S) = &operator==;
}

But gcc gives an error

test.cc: In function ‘int main()’:
test.cc:6:30: error: ‘operator==’ not defined
   bool (*f)(S, S) = &operator==;
                              ^

which can be fixed by declaring an operator in the (global) namespace:

bool operator==(S, S);

Is there a way to accept the address without reusing the operator?

Answer 1

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Answer 2

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