anchor.diff:  
       GroupLevel = QueryArgs#view_query_args.group_level,
       case {ViewType, GroupLevel, IsMultiGet} of
  -        {reduce, exact, true} ->
  -            QueryArgs;
  -        {reduce, _, false} ->
  -            QueryArgs;
  -        {reduce, _, _} ->
  -            % we can simplify code if we just drop this error message.
  -            Msg = <<"Multi-key fetchs for reduce "
  -                    "view must include `group=true`">>,
  -            throw({query_parse_error, Msg});
  -        _ ->
  -            QueryArgs
  +    {reduce, exact, true} ->
  +        QueryArgs;
  +    {reduce, _, false} ->
  +        QueryArgs;
  +    {reduce, _, _} ->
  +        % we can simplify code if we just drop this error message.
  +        Msg = <<"Multi-key fetchs for reduce "
  +                "view must include `group=true`">>,
  +        throw({query_parse_error, Msg});
  +    _ ->
  +        QueryArgs
       end,
       QueryArgs.
   
  
positive.code:     couch_httpd:etag_respond(Req, CurrentEtag, fun() ->
          {ok, RowCount} = couch_view:get_row_count(View),
          FoldAccInit = {Limit, SkipCount, undefined, []},
          {LastReduce, FoldResult} = lists:foldl(
              fun(Key, {_, FoldAcc}) ->
                  FoldlFun = make_view_fold_fun(Req,
                      QueryArgs#view_query_args{
                      }, CurrentEtag, Db, Group#group.current_seq, RowCount,
                      #view_fold_helper_funs{
                          reduce_count = fun couch_view:reduce_to_count/1
                      }),
                  {ok, LastReduce, FoldResult} = couch_view:fold(View, FoldlFun, FoldAcc, 
                      make_key_options(QueryArgs#view_query_args{start_key=Key, end_key=Key})),
                  {LastReduce, FoldResult}
              end, {{[],[]}, FoldAccInit}, Keys),
          finish_view_fold(Req, RowCount, couch_view:reduce_to_count(LastReduce), FoldResult, [{update_seq,Group#group.current_seq}])
      end).
  
  output_reduce_view(Req, Db, View, Group, QueryArgs, nil) ->
  
negative.code: 
  json_view_start_resp(Req, Etag, TotalViewCount, Offset, _Acc, UpdateSeq) ->
      {ok, Resp} = start_json_response(Req, 200, [{"Etag", Etag}]),
      BeginBody = io_lib:format(
              "{\"total_rows\":~w,\"update_seq\":~w,"
              "\"offset\":~w,\"rows\":[\r\n",
              [TotalViewCount, UpdateSeq, Offset]),
      {ok, Resp, BeginBody}.
  
  