anchor.diff:  
   -define(SERVER, ?MODULE).
   
  --record(state, {manager, pool, ctx, next_funid=1, anon_funs=[], in_batch=false}).
  +-record(state, {manager, pool, ctx, in_batch=false}).
   
   start_link(Manager, PoolName) ->
       gen_server:start_link(?MODULE, [Manager, PoolName], []).
  
positive.code:     riak_kv_js_manager:mark_idle(Pool);
  maybe_idle(#state{in_batch=true}) ->
      ok.
  
negative.code: 
  %% Internal functions
  define_invoke_anon_js(JS, Args, #state{ctx=Ctx}=State) ->
      JSFun =  define_anon_js(JS, Args),
      case invoke_js(Ctx, JSFun) of
          {ok, R} ->
              {{ok, R}, State};
          Error ->
              {Error, State}
      end.
  
  invoke_js(Ctx, JSFun) ->
      case js:eval(Ctx, JSFun) of
          {ok, {struct, R}} ->
              case proplists:get_value(<<"lineno">>, R) of
                  undefined ->
                      {ok, R};
                  _ ->
                      {error, R}
              end;
          R ->
              R
      end.
  
  invoke_js(Ctx, Js, Args) ->
  