peconv::parse_resource() question

[nblog]

auto on_res_entry_found = [](
    BYTE* modulePtr,
    IMAGE_RESOURCE_DIRECTORY_ENTRY* root_dir,
    IMAGE_RESOURCE_DATA_ENTRY* curr_entry
    ) {
        return true;
};

peconv::parse_resources(execute_pe, on_res_entry_found);

I found that "root_dir" is always the first, maybe I'm wrong. I hope there are relevant examples.