MyObject: type = {
    // some more fields
    public url: std::string;
    public operator=:(out this, url_: std::string) = {
        this.url = url_;
    }
    public operator=:(out this, in that) = {
        this.url = that.url;
    }
}

CachingMyObjectAccessor: type = {
    public operator=:(out this, obj_: *MyObject) = {
        this.obj = obj_;
        this.parsed_url = std::nullopt;
    }
    public get_domain: (inout this) -> std::string_view = {
        this.parse_url();
        return std::get<1>(parsed_url*);
    }
    public get_path: (inout this) -> std::string_view = {
        this.parse_url();
        return std::get<2>(parsed_url*);
    }
    private parse_url: (inout this) = {
        if (!parsed_url.has_value()) {
            // some expensive code
            s := std::string_view(obj*.url);
            i := s.find("//");
            j := s.find("/", i+2);
            this.parsed_url = (s.substr(0, i), s.substr(i+2, j-i-2), s.substr(j));
        }
    }
    obj: *MyObject;
    parsed_url: std::optional<std::tuple<std::string_view, std::string_view, std::string_view>>;
}

main: () -> int = {
    o: MyObject = ("http://a.b/c/d/e");
    a: CachingMyObjectAccessor = (o&);
    // oo := o;  // uncommenting this moves out of o breaking the accessor
    std::print("domain: {} path: {}", a.get_domain(), a.get_path());
    _ = a;
}