anchor.diff:      gen_server:call(?MODULE, get_interposition_funs, infinity).
   
   %% @doc
  +get_pre_interposition_funs() ->
  +    gen_server:call(?MODULE, get_pre_interposition_funs, infinity).
  +
  +%% @doc
   add_post_interposition_fun(Name, PostInterpositionFun) ->
       gen_server:call(?MODULE, {add_post_interposition_fun, Name, PostInterpositionFun}, infinity).
   
  
positive.code:          add_interposition_fun/2,
           remove_interposition_fun/1,
           get_interposition_funs/0,
           add_post_interposition_fun/2,
           remove_post_interposition_fun/1,
           inject_partition/2,
  
negative.code: 
  handle_call(get_interposition_funs, _From, #state{interposition_funs=InterpositionFuns}=State) ->
      {reply, {ok, InterpositionFuns}, State};
  
  handle_call(get_pre_interposition_funs, _From, #state{pre_interposition_funs=PreInterpositionFuns}=State) ->
      {reply, {ok, PreInterpositionFuns}, State};
  
  handle_call({add_post_interposition_fun, Name, PostInterpositionFun}, _From, #state{post_interposition_funs=PostInterpositionFuns0}=State) ->
      PostInterpositionFuns = dict:store(Name, PostInterpositionFun, PostInterpositionFuns0),
  