Macro COMMANDS 

macro_rules! COMMANDS {
    (
        $(
            $(#[$main_meta:meta])*
            $name:ident {
            $(
                $(#[$meta:meta])*
                $(($($clap_arg:stmt),*))?
                $command_name:ident {
                $(version = $version:literal)?
                $(author = $author:literal)?
                $(about = $about:literal)?
                $(
                    Args {
                        $(
                            $(#[$args_meta:meta])*
                            $args_name:ident: $args_ty:ty
                        )*
                    }
                )?

                $(
                    $(#[$subcommands_meta:meta])*
                    commands = $subcommands:ty
                )?
            })+
        })+
    ) => { ... };
}