const Value& _value;

       const Value& _value;

       Converter _converter;

       Converter _converter;

     public:

     public:

       ValueStorage(const Value& value, const Converter& converter = Converter())

       ValueStorage(const Value& value, const Converter& converter = Converter())

       virtual std::string get() {

       virtual std::string get() {

         return _converter(_value);

         return _converter(_value);

       }

       }

     };

     };