Function config_parse_regex

less_slow.cpp:4549–4568

static constexpr std::string_view regex_for_config = R"(^\s*([^#:\s]+)\s*:\s*([^#:\s]+)\s*$)";

void config_parse_regex(std::string_view config_text, std::vector<std::pair<std::string, std::string>> &settings,
                        std::regex const &regex_fsm) {
    auto begin_ptr = config_text.data();
    auto end_ptr = begin_ptr + config_text.size();

    // Use `std::cregex_iterator` to find all non-overlapping matches
    // across multiple lines. We rely on "multiline" mode to treat
    // ^ and $ as line boundaries.
    std::cregex_iterator it(begin_ptr, end_ptr, regex_fsm);
    std::cregex_iterator end_it;

    // For each match, capture the "key" and "value" groups.
    // Group 0 is the full match, 1 and 2 are our key and value.
    for (; it != end_it; ++it) {
        std::cmatch const &match = *it;
        std::string key = match.str(1);
        std::string value = match.str(2);
        settings.emplace_back(std::move(key), std::move(value));
    }
}

void parse_regex(bm::State &state, std::string_view config_text) {
    std::size_t pairs = 0, bytes = 0;