How do I return hundreds of values from a C++ function?

Question

In C++, whenever a function creates many (hundreds or thousands of) values, I used to have the caller pass an array that my function then fills with the output values:

Answer 1

Response to Edit: Well, if you need to return hundreds and thousands if values, a tuple of course would not be the way to go. Best pick the solution with the iterator then, but it's best not use any specific iterator type.

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If you use iterators, you should use them as generic as possible. In your function you have used an insert iterator like insert_iterator< vector >. You lost any genericity. Do it like this:

template
void computeValues(int input, OutputIterator output) {
    ...
}

Whatever you give it, it will work now. But it will not work if you have different types in the return set. You can use a tuple then. Also available as std::tuple in the next C++ Standard:

boost::tuple computeValues(int input) { 
    ....
}

If the amount of values is variadic and the type of the values is from a fixed set, like (int, bool, char), you can look into a container of boost::variant. This however implies changes only on the call-side. You can keep the iterator style of above:

std::vector< boost::variant > data;
computeValues(42, std::back_inserter(data));