anchor.diff:  
   %% gen_server callbacks
   init([Module, Args]) ->
  -    set_state(module, Module),
  -    init_callbacks(Module),
  -
  +    init_state(Module),
       call_callback(init, [Args], {ok, undefined}).
   
   handle_call(Request, From, State) ->
  
positive.code:     gen_server:multi_call(Nodes, Name, Req, Timeout).
  
  enter_loop(Mod, Options, State) ->
      gen_server:enter_loop(Mod, Options, State).
  
  enter_loop(Mod, Options, State, TimeoutOrServerName) ->
      gen_server:enter_loop(Mod, Options, State, TimeoutOrServerName).
  
  enter_loop(Mod, Options, State, ServerName, Timeout) ->
      gen_server:enter_loop(Mod, Options, State, ServerName, Timeout).
  
  %% gen_server2-specific APIs
  
negative.code:                           set_state({have_callback, F},
                                      erlang:function_exported(Module, F, A))
                    end, Callbacks).
  
  init_state(Module) ->
      set_state(module, Module),
      init_callbacks(Module).
  