Converts IPv4 and IPv6 to decimal (long value) in C++

ip2long.cpp

#include <iostream>
#include <boost/asio/ip/address.hpp>
#include <boost/multiprecision/cpp_int.hpp>
using big_int = boost::multiprecision::cpp_int;

big_int ip2long(const std::string&);

int main(int, char**) {
    const auto
            fals = "xxx.xxx.x.x",
            ipv4 = "192.168.1.1",
            ipv6 = "2001:4860:4860::8888";
    const auto
            fals_dec = ip2long(fals),
            ipv4_dec = ip2long(ipv4),
            ipv6_dec = ip2long(ipv6);
    std::cout
        << "FALSE: " << fals << " -> " << fals_dec << std::endl
        << " IPv4: " << ipv4 << " -> " << ipv4_dec << std::endl
        << " IPv6: " << ipv6 << " -> " << ipv6_dec << std::endl;
    /**
      output:
        FALSE: xxx.xxx.x.x -> 0
         IPv4: 192.168.1.1 -> 3232235777
         IPv6: 2001:4860:4860::8888 -> 42541956123769884636017138956568135816
      ref:
        IPv4: https://www.ipaddressguide.com/ip
        IPv6: https://www.ipaddressguide.com/ipv6-to-decimal
    **/
    return EXIT_SUCCESS;
}
/**
 * @brief ip2long converts IP to long value
 * @param ip_addr the input IP (IPv4 or IPv6)
 * @return cpp_int as the IP's long value
 * @author Dariush Hasanpour <[email protected]>
 */
big_int ip2long(const std::string& ip_addr) {
    // the output's default value
    big_int decimal = 0;
    // try to compute the decimal value of the input
    try {
        // convert the string IP into the boost IP object
        auto addr = boost::asio::ip::make_address(ip_addr);
        // check if the IP is v4 type
        if (addr.is_v4()) {
            // just convert it to `uint` as it's decimal
            decimal = addr.to_v4().to_uint();
        // check if the IP is v6 type
        } else if (addr.is_v6()) {
            // get the v6's bytes
            auto bytes = addr.to_v6().to_bytes();
            // compute the decimal value from the array of hexa-decimal values
            for (int i = 0; i < sizeof(bytes); i++)
            	decimal = (decimal << 0x8) | bytes[i];
        }
    } catch(...) { /* ignore if anything raises */ }
    // return decimal value of the input IP
    return decimal;
}