61 lines
1.4 KiB
C++
61 lines
1.4 KiB
C++
// frnd2tmp.cpp -- template class with non-template friends
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#include <iostream>
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using std::cout;
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using std::endl;
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template <typename T>
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class HasFriend
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{
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private:
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T item;
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static int ct;
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public:
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HasFriend(const T & i) : item(i) {ct++;}
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~HasFriend() {ct--; }
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friend void counts();
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friend void reports(HasFriend<T> &); // template parameter
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};
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// each specialization has its own static data member
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template <typename T>
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int HasFriend<T>::ct = 0;
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// non-template friend to all HasFriend<T> classes
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void counts()
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{
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cout << "int count: " << HasFriend<int>::ct << "; ";
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cout << "double count: " << HasFriend<double>::ct << endl;
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}
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// non-template friend to the HasFriend<int> class
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void reports(HasFriend<int> & hf)
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{
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cout <<"HasFriend<int>: " << hf.item << endl;
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}
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// non-template friend to the HasFriend<double> class
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void reports(HasFriend<double> & hf)
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{
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cout <<"HasFriend<double>: " << hf.item << endl;
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}
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int main()
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{
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cout << "No objects declared: ";
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counts();
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HasFriend<int> hfi1(10);
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cout << "After hfi1 declared: ";
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counts();
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HasFriend<int> hfi2(20);
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cout << "After hfi2 declared: ";
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counts();
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HasFriend<double> hfdb(10.5);
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cout << "After hfdb declared: ";
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counts();
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reports(hfi1);
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reports(hfi2);
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reports(hfdb);
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// std::cin.get();
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return 0;
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}
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