rem: if (str[0] == 'q' || str[0] == 'Q')
add: if (str.empty() || str[0] == 'q' || str[0] == 'Q')
context: main(){    cout << "/////////////////////////////////////////////////////////\n\n";    cout << "\t\tA number parser implemented as a functor for Spirit...\n\n";    cout << "/////////////////////////////////////////////////////////\n\n";    cout << "Give me an integer number command\n";    cout << "Commands:\n";    cout << "  A <num> --> parses a single number\n";    cout << "  B <num>, <num>, ... --> parses a series of numbers ";    cout << "separated by commas\n";    cout << "  Q --> quit\n\n";    string str;    while (getline(cin, str))    {        if (str[0] == 'q' || str[0] == 'Q')            break;        else if (str[0] == 'a' || str[0] == 'A')        {            int n;            if (parse_number(str.c_str()+1, n))            {                cout << "-------------------------\n";                cout << "Parsing succeeded\n";                cout << str << " Parses OK: " << n << endl;                cout << "-------------------------\n";            }            else            {                cout << "-------------------------\n";                cout << "Parsing failed\n";                cout << "-------------------------\n";            }        }        else if (str[0] == 'b' || str[0] == 'B')        {            std::vector<int> n;            if (parse_numbers(str.c_str()+1, n))            {                cout << "-------------------------\n";                cout << "Parsing succeeded\n";                int size = n.size();                cout << str << " Parses OK: " << size << " number(s): " << n[0];                for (int i = 1; i < size; ++i) {                    cout << ", " << n[i];                }                cout << endl;                cout << "-------------------------\n";            }            else            {                cout << "-------------------------\n";                cout << "Parsing failed\n";                cout << "-------------------------\n";            }        }        else        {            cout << "-------------------------\n";            cout << "Unrecognized command!!";            cout << "-------------------------\n";        }    }    cout << "Bye... :-) \n\n";    return 0;}