#include <string>

#include <sstream>

struct as_string {};

inline std::string operator<< ( std::ostream & streamOut, const as_string &)

{

    std::ostringstream & s = ( std::ostringstream &)streamOut;

    return s.str();

}

int main()

{

    int nWordsCount;

    // ... calculate words count

    nWordsCount = 48;

    std::string str =

        // construct a temporary stringstream and use it;

        // the as_string() will convert all to a string

        std::ostringstream() << "We have " << nWordsCount << " words" << as_string();

    return 0;

}