Required arguments about cxxopts

[jarro2783]

I'm reluctant to do this, and something similar was raised in #25. The reason being that I don't think the parser should have any logic in it. The problem is that in general, you can't just say that an argument is required or not. There are some specific cases where it works, but a lot of the time, arguments are required based on the presence of other arguments. I would rather leave that logic up to the program.

[crusader-mike]

I agree with OP -- simple method will certainly simplify my life (as in I don't need to write it myself). Something very trivial, like:

class Options {
...
template<class T>
T const& required(string const& opt)
{
    if (!count(opt))
        throw ...(u8"Option ‘%s’ is required", opt.c_str());
    return (*this)[opt].as<T>();
}
...
};

Also, you may want to clean up this code a bit -- I skimmed over it and noticed few strange pieces (like calling std::move on string const&). Don't take it personally -- it is a neat little library and it seem to get it's task done.

[jarro2783]

I'll see if I can add something simple for required options. It seems to be the most requested feature, and something simple should be ok. As long as it is understood that anything more complicated belongs in the main program.

Thanks for pointing out the strange things in it. It has been around for a while and acquired some cruft.

[patrikhuber]

Hi,

I have been searching for this for quite a while. I don't think this is documented anywhere. Shall we add this to the wiki? It's meant to be used as follows, correct?

cxxopts::check_required(options, { "option1", "option2" });