/*
   Value Based Semantics
   must have 
   1) default constructor
   2) overload of assignment
   3) copy constructor
   4) destructor

   Ken Moore
   Spring 2004
*/

#include<iostream>
using namespace std;

// class to wrap an array and check for
// out of bounds
class aWrap{
private:
	int num;
	int *a;
public:

	// default constructor
	aWrap():num(10),a(new int[10]){}
	/* same as
	aWrap(){
	   num = 10;
	   a = new int[10];
	}
	*/
	// overload constructor
	aWrap(int n):num(n),a(new int[n]){}
	
	// copy constructor
	aWrap(aWrap &aw){
			if(this->a){
				delete [] this->a;
			}
			this->num = aw.num;
			this->a = new int[this->num];
			for(int i = 0; i < this->num; i++)
				this->a[i] = aw[i];
	}
	
	// overload [] operator 
	int & operator[](int i){
		if(i>=0&&i<=num)
			return a[i];
		else
			cout << "OUT OF BOUNDS " << i << endl;
		return i;
	}

	// overload assignment operator =
	// note this-> is implied and can be totally removed
	// with no effect on the code.  Most programmers never
	// use this-> unless it is to disambiguate
	aWrap& operator=(aWrap & aw){

		// check for self assignment
		if(this != &aw){
			if(this->a){
				delete [] this->a;
			}

			// copy into new array
			this->num = aw.num;
			this->a = new int[this->num];
			for(int i = 0; i < this->num; i++)
				this->a[i] = aw[i];
		}

		return *this;
	}
	
	// destructor
	~aWrap(){
		cout << "In d-tor" << endl;
		delete [] a;
	}
	
	friend ostream& operator << (ostream& o, aWrap &aw);
};
ostream& operator << (ostream& o, aWrap &aw){
	for(int i = 0; i < aw.num; i++)
		o << aw[i] << endl;
	return o;
}
void main(){
	aWrap arr(5);
	// arr[i] = arr.[](i)
	for(int i = 0; i < 5; i++){ 
		arr[i] = i + 1;
	}
	arr[6]=17;
	cout << arr << endl;
	aWrap ar(5);

	// call assignment operator ar.=(arr)
	ar = arr;
	cout << ar << endl;

	// call copy constructor 
	aWrap x(ar);
	cout << x << endl;


}