I have the separate_by_delimiter function which is used inside another function outside_func

std::vector<std::string>
separate_by_delimiter(std::istream &input, int num_separators, char delimiter) {
    std::vector<std::string> separated_list;
    std::string segment;
    std::stringstream input_stream;
    for (int i = 0; i < num_separators; i++) {
        std::getline(input, segment, delimiter);
        input_stream << segment << delimiter;
    }
    while (std::getline(input_stream, segment, delimiter)) {
        separated_list.insert(separated_list.begin(), segment);
    }
    return separated_list;
}

const int n = 10; // just as an example
void outside_func(std::istream &input) {
    auto split_list = separate_by_delimiter(input, n, ',');
    input >> x; // x defined earlier
}

As you can see separate_by_delimiter relies on how many separators (delimiters) are in the input so it can create a std::vector<std::string> (not including the part after the last delimiter as it must be passed to another variable)

How can this be done without specifying the number of separators?