//: C05:BearCorner.h // From "Thinking in C++, Volume 2", by Bruce Eckel & Chuck Allison. // (c) 1995-2004 MindView, Inc. All Rights Reserved. // See source code use permissions stated in the file 'License.txt', // distributed with the code package available at www.MindView.net. #ifndef BEARCORNER_H #define BEARCORNER_H #include using std::ostream; // Item classes (traits of guests): class Milk { public: friend ostream& operator<<(ostream& os, const Milk&) { return os << "Milk"; } }; class CondensedMilk { public: friend ostream& operator<<(ostream& os, const CondensedMilk &) { return os << "Condensed Milk"; } }; class Honey { public: friend ostream& operator<<(ostream& os, const Honey&) { return os << "Honey"; } }; class Cookies { public: friend ostream& operator<<(ostream& os, const Cookies&) { return os << "Cookies"; } }; // Guest classes: class Bear { public: friend ostream& operator<<(ostream& os, const Bear&) { return os << "Theodore"; } }; class Boy { public: friend ostream& operator<<(ostream& os, const Boy&) { return os << "Patrick"; } }; // Primary traits template (empty-could hold common types) template class GuestTraits; // Traits specializations for Guest types template<> class GuestTraits { public: typedef CondensedMilk beverage_type; typedef Honey snack_type; }; template<> class GuestTraits { public: typedef Milk beverage_type; typedef Cookies snack_type; }; #endif // BEARCORNER_H ///:~