anchor.diff:      }
       return this;
     }
  -  
  +
     String getQueryString(){
       var result = JSON.encode(map);
       result = result.replaceAllMapped(objectIdRegexp, (Match match)=>'ObjectId("${match.group(1)}")');
       return result;
  -  }  
  +  }
   
   }
  
positive.code:         dotAll:dotAll,extended:extended)});
      return this;
    }
    
    SelectorBuilder inRange(String fieldName, min, max, {bool minInclude: true, bool maxInclude: false}) {
      Map rangeMap = {};
      if (minInclude){
  
negative.code: 
  
    SelectorBuilder fields(List<String> fields) {
      if (paramFields == null) {
        paramFields = {};
      }
      for (var field in fields) {
        paramFields[field] = 1;
      }
      return this;
    }
    SelectorBuilder excludeFields(List<String> fields) {
      if (paramFields == null) {
        paramFields = {};
      }
      for (var field in fields) {
        paramFields[field] = 0;
      }
  