Getting the compiler to perceive << as defined for a specific class

Question

Hello everyone.

I edited a post of mine with this question, yet got no answers.

I overloaded << for a class, Score (defined in score.h), in score.cpp.

ostream& operator<< (ostream & os, const Score & right)
{
 os << right.getPoints() << " " << right.scoreGetName();
 return os;
}

(getPoints fetches an int attribute, getName a string one)

I get this compiling error for a test in main(), contained in main.cpp

binary '<<' : no operator found which takes a right-hand operand of type 'Score' (or there is no acceptable conversion)

How come the compiler doesn't 'recognize' that overload as valid? (includes are proper)

Thanks for your time.

EDIT:

As requested, code causing the error:

cout << ":::::\n" << jogador.getScore() << endl;

jogador is a Player object, which contains a Score one. getScore returns that attribute.

Answer 1

Perhaps you didn't declare your operator<< in score.h? It should normally contain something like:

ostream& operator<< (ostream & os, const Score & right);

Edit: More accurately, that should be:

std::ostream &operator<<(std::ostream &os, const Score &right);

You definitely should not have a using namespace std; in a header, so you need the std:: for it to work correctly.

Answer 2

Try declaring operator<< as a friend function in your class:

struct Score
{
  friend ostream& operator<<(ostream& output, const Score& right);
};

This will allow your Score structure to fit nicely into printing statements:

Score my_score;
cout << my_score << endl;

When in doubt, check the C++ FAQ.