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19

LISTING19.3 Nontemplate Friend Function

0: // Listing 19.3 - Type specific friend functions in templates

1:

2: #include <iostream>

3: using namespace std;

4:

5: const int DefaultSize = 10;

6:

7: // declare a simple Animal class so that we can

8: // create an array of animals

9:

10: class Animal

11: {

12: public:

13: Animal(int);

14: Animal();

15: ~Animal() {}

16: int GetWeight() const { return itsWeight; }

17: void Display() const { cout << itsWeight; }

18: private:

19: int itsWeight;

20: };

21:

22: Animal::Animal(int weight):

23: itsWeight(weight)

24: {}

25:

26: Animal::Animal():

27: itsWeight(0)

28: {}

29:

30: template <class T> // declare the template and the parameter

31: class Array // the class being parameterized

32: {

33: public:

34: // constructors

35: Array(int itsSize = DefaultSize);

36: Array(const Array &rhs);

37: ~Array() { delete [] pType; }

38:

39: // operators

40: Array& operator=(const Array&);

41: T& operator[](int offSet) { return pType[offSet]; }

42: const T& operator[](int offSet) const

43: { return pType[offSet]; }

44: // accessors

45: int GetSize() const { return itsSize; }

46:

47: // friend function