Accessing subsubcommand matches

[kirillbobyrev]

From what I have seen it is not clear how a sub-subcommand matches should be accessed.

What I expect to see is something like

let matches = App::from_yaml(yml).get_matches();
let subcommand_matches = matches.subcommand_matches(matches.subcommand_name().unwrap());
let subsubcommand_matches = subcommand_matches.subcommand_matches(matches.subcommand_name().unwrap());

However, I get

error: no method named `subcommand_matches` found for type `std::option::Option<&clap::ArgMatches<'_>>` in the current scope

With

rustc 1.13.0
clap-rs 2.19.1

Am I just missing something or is such kind of subsubcommand extraction not supported?

[kbknapp]

It's not the typical way to do it, but you can change your code to work below:

let matches = App::from_yaml(yml).get_matches();

// subcommand_matches returns an option
let subcommand_matches = matches.subcommand_matches(matches.subcommand_name().unwrap()).unwrap();

let subsubcommand_matches = subcommand_matches.subcommand_matches(matches.subcommand_name().unwrap()).unwrap();

The more common way to do this is:

match matches.subcommand() {
    ("foo", Some(foo_matches)) => {
        // Handle the myprog foo subcommand
    },
    ("bar", Some(bar_matches)) => {
        // Handle myprog bar subcommand
        match bar_matches.subcommand() {
            ("baz", Some(baz_matches)) => {
                // handle myprog bar baz subcommand
             },
             _ => unreachabe!()
        }
    },
    _ => unreachabe!()
}

etc.

[kirillbobyrev]

Great, thank you once again and apologies for a newbie question.

Do you think it's worth adding such example to examples/? Even though there are great examples, I would actually love to see even more as a newcomer.

[kbknapp]

For sure! We can always use more examples. I'll add it on my next doc sweep unless someone else beats me to it.