+ int ReadDouble(const string & param, double * val, double defaultVal) const;
+
+ void WriteString(const string & param, const char * val) { return WriteString(param, std::string(val)); }
+ void WriteString(const string & param, const string & val);
+ void WriteInt(const string & param, int64_t val);
+ void WriteDouble(const string & param, double val);