private:
void appearance(const std::string &);
void color(const std::string &, unsigned, unsigned, unsigned);
private:
void appearance(const std::string &);
void color(const std::string &, unsigned, unsigned, unsigned);
void set_appearance(const std::string &, const Appearance &);
const Appearance &get_appearance(const std::string &) const;
void set_appearance(const std::string &, const Appearance &);
const Appearance &get_appearance(const std::string &) const;