anchor.diff:  
   
     Future addAll(List<Map> data, String author) {
  +    for (Map d in data) ensureId(d, idgen);
       cache.invalidate();
       num nextVersion;
       return _get_locks().then((_) => _maxVersion).then((version) {
  
positive.code:       .catchError((e, s) => _release_locks().then((_) => _processError(e, s)));
    }
  
    static stripCollectionName(Map doc){
      //modifikuje doc
      if (doc.containsKey(COLLECTION_NAME)) doc.remove(COLLECTION_NAME);
  
negative.code: 
  MongoProvider mpClone(MongoProvider source){
  
    MongoProvider m = new MongoProvider.config(source.collection,
        source._collectionHistory, source._lock, source.cache, source.idgen);
    m._selectorList = new List.from(source._selectorList);
    m._sortParams = new Map.from(source._sortParams);
    m._limit = source._limit;
  