anchor.diff:    }
   
     Future<List> index([Map params]) async {
  -    return items.keys
  -        .where((index) => items[index] != null)
  -        .map((index) => _makeJson(index, items[index]))
  -        .toList();
  +    List result = [];
  +
  +    for (int i = 0; i < items.length; i++) {
  +      result.add(_makeJson(i, items[i]));
  +    }
  +
  +    return result;
     }
   
     Future read(id, [Map params]) async {
       int desiredId = int.parse(id.toString());
  -    if (items.containsKey(desiredId)) {
  +    if (items.length > desiredId) {
         MemoryModel found = items[desiredId];
         if (found != null) {
           return _makeJson(desiredId, found);
  
positive.code: 
    Future update(id, data, [Map params]) async {
      int desiredId = int.parse(id.toString());
      if (items.containsKey(desiredId)) {
        try {
          items[desiredId] =
          (data is Map) ? god.deserializeDatum(data, outputType: T) : data;
  
negative.code: 
    Future modify(id, data, [Map params]) async {
      int desiredId = int.parse(id.toString());
      if (items.length > desiredId) {
        try {
          Map existing = god.serializeObject(items[desiredId]);
          data = mergeMap([existing, data]);
  