anchor.diff:      return task.future;
     }
   
  -  Future<List<Object>> mget(List<String> keys){
  +  Future<List<Object>> mget(List<String> allKeys){
       Completer<Object> task = new Completer<List<Object>>();
       List<Object> values = [];
  -    keys.forEach((x) =>
  -      if (_keys.containsKey(x)) values.add(v)
  -    );
  +    allKeys.forEach((x){
  +      if (_keys.containsKey(x)) values.add(_keys[x]);
  +    });
       task.complete(values);
       return task.future;
     }
  
positive.code:   Future incr(String key){
      Completer task = new Completer();
      var counter = _keys[key];
      counter = counter == null ? 1 : Math.parseInt(counter.toString())++;
      _keys[key] = counter;
      task.complete(counter);
      return task.future;
  
negative.code:   Future<List<String>> keys(String pattern){
      Completer<List<String>> task = new Completer<List<String>>();
      List<Object> values = [];
      _keys.forEach((k,v){
        if (_globMatch(k, pattern)) values.add(v);
      });
      task.complete(values);
      return task.future;
    }
  