Can a std::back_insert_iterator be used on a std::ostream?

Question

As per the title question.

I assume that the answer is "No, because the std::back_insert_iterator object calls push_back() on the container."

If the answer is in fact no, then is there any template class iterator that I can use in my template function to both append to a std::string, append to a std::vector<char>, and write to an std::ostream?

Answer 1

This is what std::ostream_iterator is for:

#include <iostream>
#include <string>
#include <vector>
#include <iterator>
#include <algorithm>

int main()
{
    char c[] = { 'a', 'b', 'c', 'd' };

    std::vector<char> v;
    std::string s;

    std::copy(c, c+4, std::back_inserter(v));
    std::copy(c, c+4, std::back_inserter(s));
    std::copy(c, c+4, std::ostream_iterator<char>(std::cout));
}

DEMO