title: What is for the Index option in TRemotable derivated classes?
body: <p>When WSDL importer wizard generates the interfaces, all properties have the Index option, but reading the code and the InvokeRegistry unit, I can't found what is that for, anyone know if it is really necessary?</p>
  
  <p>Like this</p>
  
  <pre><code>  Login = class(TRemotable)
    private
      [...] 
    published
      property User: string Index (IS_OPTN) read GetUser write SetUser stored User_Specified;
      [...]
    end;
  </code></pre>
  
  <p>I'm asking because I want to change this unit, adding some Interfaces to this classes, for integrate with MVP framework.</p>