anchor.diff:      {stop, term(), tuple()}.
   
   handle_cast(Msg, State, PosMod, PosUser) ->
  -    SubMod = element(PosMod, State),
  -    User = element(PosUser, State),
  -    case erlang:function_exported(SubMod, handle_cast, 2) of
  -        true ->
  -            proc_reply(SubMod:handle_cast(Msg, User), PosUser, State);
  +    handle_cast(handle_cast, Msg, State, PosMod, PosUser).
  +
  +
  +%% @private
  +-spec handle_cast(atom(), term(), tuple(), pos_integer(), pos_integer()) ->
  +    {noreply, tuple()} |
  +    {noreply, tuple(), timeout() | hibernate} |
  +    {stop, term(), tuple()}.
  +
  +handle_cast(Fun, Msg, State, PosMod, PosUser) ->
  +    SubMod = element(PosMod, State),
  +    User = element(PosUser, State),
  +    case erlang:function_exported(SubMod, Fun, 2) of
  +        true ->
  +            proc_reply(SubMod:Fun(Msg, User), PosUser, State);
           false ->
               {noreply, State}
       end.
  
positive.code: -module(nklib_gen_server).
  -author('Carlos Gonzalez <carlosj.gf@gmail.com>').
  
  -export([init/4, handle_call/5, handle_cast/4, handle_info/4, terminate/4, 
           code_change/5, handle_any/5]).
  -include("nklib.hrl").
  
  
  
negative.code:     {stop, term(), tuple()}.
  
  handle_call(Msg, From, State, PosMod, PosUser) ->
      handle_call(handle_call, Msg, From, State, PosMod, PosUser).
  
  
  %% @private
  -spec handle_call(atom(), term(), {pid(), term()}, tuple(), 
                    pos_integer(), pos_integer()) ->
      {reply, term(), tuple()} |
      {reply, term(), tuple(), timeout() | hibernate} |
      {noreply, tuple()} |
      {noreply, tuple(), timeout() | hibernate} |
      {stop, term(), term(), tuple()} |
      {stop, term(), tuple()}.
  
  handle_call(Fun, Msg, From, State, PosMod, PosUser) ->
      SubMod = element(PosMod, State),
      User = element(PosUser, State),
      case erlang:function_exported(SubMod, Fun, 3) of
          true ->
              proc_reply(SubMod:Fun(Msg, From, User), PosUser, State);
          false ->
              {noreply, State}
      end.
  