Boost Program_options Demo (for a RSS Reader

rss-reader-opts.cpp

// rss-reader-opts.cpp
// This program demonstrates the use of Boost.ProgramOptions to handle command line arguments
// for a simple RSS reader application. It allows users to list, read, add, and delete feeds.
// To Build: clang++ -O3 -std=c++11 -lboost_program_options rss-reader-opts.cpp -o rss-read
#include <string>
#include <vector>
#include <boost/program_options.hpp>
namespace po = boost::program_options;

#include <iostream>
#include <iterator>
using namespace std;

int main(int ac, char* av[])
{
    try {

        po::options_description desc("Allowed options");
        desc.add_options()
            ("help,h", "produce help message")
            ("list,l","list available Feeds")
            ("read,r", po::value<int>(),"read Feed by ID")
            // new option for adding feeds that takes two arguments. One for the feed name and another for the URL
            ("add,a", po::value<std::vector<std::string>>()->multitoken(), "add Feed with name and URL")
            ("delete,d", po::value<bool>(),"delete Feeds")
        ;

        po::variables_map vm;        
        po::store(po::parse_command_line(ac, av, desc), vm);
        po::notify(vm);    

        if (vm.count("help")) {
            cout << desc << "\n";
            return 0;
        }

        if (vm.count("list")) {
            cout << "Listing available Feeds.\n";
        } else if (vm.count("read")) {
            cout << "Reading Feed with ID: " 
                 << vm["read"].as<int>() << ".\n";
        } else if (vm.count("add")) {
            // Check if the vector has exactly two elements
            if (vm["add"].as<std::vector<std::string>>().size() != 2) {
                cerr << "Error: --add requires exactly two arguments: feed name and URL.\n";
                return 1;
            }
            // Accessing the vector of strings for the feed name and URL
            cout << "Adding Feed: " 
                 << "Feed Name: " << vm["add"].as<std::vector<std::string>>()[0] << "\n"
                 << "Feed URL: " << vm["add"].as<std::vector<std::string>>()[1] << "\n";
        } else if (vm.count("delete")) {
            cout << "Deleting Feed.\n";
        } 
        else {
            cout << "No valid option provided.\n";
        }
    }
    catch(exception& e) {
        cerr << "error: " << e.what() << "\n";
        return 1;
    }
    catch(...) {
        cerr << "Exception of unknown type!\n";
    }

    return 0;
}

This is based on an example distributed with the Boost Documentation examples.