Overload problem

[ramp00]

I'm trying to cout the vector temperatures, but I get the error:
"no operator "<<" matches these operands. Operand types are: std::ostream << Temps"
Would appreciate any answers. Point out any mistakes you see or things that could be done in a better way, and I'll try to implement the tips:)

temps.h

  struct Temps {
	vector<Temps> temperatures;
	double max;
	double min;
	friend istream& operator>>(istream& is, Temps& t);
};

temps.cpp

istream& operator>>(istream& is, Temps& t) {
	is >> t.max >> t.min;
	return is;
}

ostream& operator<<(ostream& o, const Temps& t) {
	vector<Temps> f = t.temperatures;
	for (auto x : f) {
		o << x;
	}
	return o;
}

main.cpp

int main(){
	setlocale(LC_ALL, "norwegian");
	ifstream is;
	is.open("temperatures.txt");

	if (!is) {
		error("Could not read file", "temperatures.txt");
	}
	Temps temp;
	while (is >> temp) {
		(temp.temperatures).push_back(temp);
	}
	cout << temp;

	return 0;
}

[salem c]

> friend istream& operator>>(istream& is, Temps& t);
You need to friend your << operator as well.

[lastchance]

You also need a declaration of your stream insertion (<<) operator in temps.h; otherwise main.cpp (where it is presumably include'd - you don't show that) won't know it exists.

There's nothing in Temps that is private. I'm not sure that it matters whether the user-defined operator is a friend or not.

I'm also not sure that it makes sense to put
vector<Temps> temperatures;
inside Temps. Why don't you just declare that in your main() procedure.

[ramp00]

Thanks guys