Wrong value for nargout in subsref of type {}, .

I am overloading subsref in a class which implements a list.

 function [varargout] = subsref(this, index)
     switch index(1).type

         case {'{}'}
             vResult = this.GetItem(index(1).subs{:});
             nResult = length(index);
             if 1 == nResult
                 [varargout{1}] = vResult;
             else
                 [varargout{1:nargout}] = builtin('subsref', vResult, index(2:nResult));
             end
         otherwise
             [varargout{1:nargout}] = builtin('subsref',this,index);
         end

When I do the following:

list = ArrayList();                % new instance of my list class
sig = Simulink.Signal();           % create another object
list.Add(sig);                     % add the object to my list
list{1}.disp();                    % call a method without a return value

I get the error:

??? Error using ==> disp
Too many output arguments.

This is because nargout returns 1 in my subsref method but builtin('subsref', ...) doesn't return anything.

[varargout{1:nargout}] = builtin('subsref', vResult, index(2:nResult));

I can change the value of nargout implementing the numel method. However, the number of return values depends on the method I call (disp in this case) and not the indeces supplied to {}. But in numel I only get the indices of {}.

Is there a solution for this problem?