anchor.diff:          {msg, Msg2Name} ->
               UnpackFnName = mk_c_fn(u_msg_, Msg2Name),
               [?f("~s = ~s(env, &~s);\n",
  -                [DestVar, UnpackFnName, SrcExpr])];
  -        {map, KeyType, ValueType} ->
  -            {KeyDest, ValueDest} = DestVar,
  -            {KeyExpr, ValueExpr} = SrcExpr,
  -            [format_nif_cc_field_unpacker_by_type(KeyDest, KeyExpr,
  -                                                  KeyType, Defs),
  -             format_nif_cc_field_unpacker_by_type(ValueDest, ValueExpr,
  -                                                  ValueType, Defs)]
  +                [DestVar, UnpackFnName, SrcExpr])]
       end.
   
   format_nif_cc_field_unpacker_repeated(DestVar, MsgVar, Field, Defs) ->
  
positive.code:     {Warns, Opts1} = possibly_adjust_typespec_opt(IsAcyclic, Opts0),
      Opts2 = normalize_return_report_opts(Opts1),
      AnRes = analyze_defs(Defs, Opts2),
      case verify_opts(Opts2) of
          ok ->
              Res1 = do_proto_defs(Defs, clean_module_name(Mod), AnRes, Opts2),
              return_or_report_warnings_or_errors(Res1, Warns, Opts2,
                                                  get_output_format(Opts2));
          {error, OptError} ->
              return_or_report_warnings_or_errors({error, OptError}, [], Opts2,
                                                  get_output_format(Opts2))
      end.
  
  
  %% @spec msg_defs(Mod, Defs) -> CompRet
  
negative.code:     erl_syntax:tuple(
        [erl_syntax:tuple([erl_syntax:atom(service),
                           erl_syntax:atom(ServiceName)]),
         rpcs_def_tree(Rpcs, Opts)]).
  
  get_rpc_format_by_opts(Opts) ->
      case proplists:get_bool(defs_as_proplists, proplists:unfold(Opts)) of
  