C++11函数返回多个不同类型的值

std::tuple<bool, std::vector<std::string> > find_urls(const std::string& content) {
    ...
	return std::make_tuple(true, urls);
}

bool error = false;
std::vector<std::string> urls;

std::string content = "..."

std::tie(error, urls) = find_urls(content);
if (error) {
	parse_content(urls)
}

auto result = find_urls(content);
if (std::get<0>(result)) {
	parse_content(std::get<1>(result));
}