}
template <typename T, typename F>
inline
void MaybeSet(const std::map<std::string, std::string> & options, const std::string & name, T & res, F conv)
{
}
template <typename T, typename F>
inline
void MaybeSet(const std::map<std::string, std::string> & options, const std::string & name, T & res, F conv)
{