dev.cpp

#include <gears/optparse.hpp>
#include <iostream>

namespace opt = gears::optparse;
int main(int argc, char** argv) {
    int stuff = 0;
    opt::option_parser parser = {{
        {"stuff", "modifies stuff", opt::bind_to(stuff) },
        {'f', "returns 42", opt::constant(42) },
        {"test", 't', "requires a value", opt::value<int>() },
        {"list", 'l', "requires a list", opt::list<std::vector<int>>(3) },
        {"compose", 'c', "composes", opt::compose<std::vector<int>>() }
    }};
    parser.program_name = "dev";
    parser.description = "A test program to test the different ways of handling command line arguments.";
    auto&& args = parser.parse(argv, argv + argc);

    if(args.options.is_active("list")) {
        std::cout << "list:\n";
        for(auto&& i : args.options.get<std::vector<int>>("list")) {
            std::cout << i << '\n';
        }
    }

    if(args.options.is_active('f')) {
        std::cout << "f has returned: " << args.options.get<int>('f') << '\n';
    }

    if(args.options.is_active("test")) {
        std::cout << "test has returned: " << args.options.get<int>("test") << '\n';
    }

    if(args.options.is_active("compose")) {
        std::cout << "compose:\n";
        for(auto&& i : args.options.get<std::vector<int>>("compose")) {
            std::cout << i << '\n';
        }
    }

    if(!args.positional.empty()) {
        std::cout << "positional: \n";
        for(auto&& i : args.positional) {
            std::cout << i << '\n';
        }
    }

    std::cout << "stuff: " << stuff << '\n';
}

stdout

danny@debian:~/Documents/GitHub/Gears$ ./dev
stuff: 0
danny@debian:~/Documents/GitHub/Gears$ ./dev --stuff=42
stuff: 42
danny@debian:~/Documents/GitHub/Gears$ ./dev -f --stuff=20
f has returned: 42
stuff: 20
danny@debian:~/Documents/GitHub/Gears$ ./dev -c 10 --stuff=40 -c 20
compose:
10
20
stuff: 40
danny@debian:~/Documents/GitHub/Gears$ ./dev -t 10 --list 1 2 3 -c 10 --stuff=20 -c 30 -- 1 2 3
list:
1
2
3
test has returned: 10
compose:
10
30
positional: 
1
2
3
stuff: 20
danny@debian:~/Documents/GitHub/Gears$ ./dev --help
usage: dev [options...]
A test program to test the different ways of handling command line arguments.

options:
    -h, --help            shows this message and exits
        --stuff           modifies stuff
    -f                    returns 42
    -t, --test            requires a value
    -l, --list            requires a list
    -c, --compose         composes