// Programmer:  Aaron Shbeeb
// File:  Pair.h
// Created:  10-25-02
// Updated:  08-13-02

#ifndef PAIR_H
#define PAIR_H

#include <assert.h>
#include "../Keywords.h"

namespace ShbeebLib
{

template <class X, class Y>
class Pair_Rep
{
public:
	X x;
	Y y;
};

template <class X, class Y>
class Pair
{
public:
	//Basic Operations
	X& x();	//Cheap form of accessor
	Y& y();

	bool operator==(preserves Pair<X,Y>& p);

	//Constructor/Destructor
	Pair();
	~Pair();

	//Standard Operations
	void Clear();
	void operator &=(alters Pair<X,Y>& p);
	
private:
	Pair_Rep<X,Y> *rep;

protected:
	void Initialize();
	void Finalize();
};

//Basic Operations
template <class X, class Y>
X& Pair<X,Y>::
x()
{
	return rep->x;
}

template <class X, class Y>
Y& Pair<X,Y>::
y()
{
	return rep->y;
}

template <class X, class Y>
bool Pair<X,Y>::
operator==(preserves Pair<X,Y>& p)
{
	if(rep->x == p.rep->x && rep->y == p.rep->y) return true;
	return false;
}

//Constructor/Destructor
template <class X, class Y>
Pair<X,Y>::
Pair()
{
	Initialize();
}

Pair<int,int>::
Pair()
{
	Initialize();
	rep->x = 0;
	rep->y = 0;
}

template <class X, class Y>
Pair<X,Y>::
~Pair()
{
	Finalize();
}

//Standard Operations
template <class X, class Y>
void Pair<X,Y>::
Clear()
{
	Finalize();
	Initialize();
}

template <class X, class Y>
void Pair<X,Y>::
operator &=(alters Pair<X,Y>& p)
{
	Pair_Rep<X,Y> *tmp;

	tmp = rep;
	rep = p.rep;
	p.rep = tmp;
}

//Protected Operations
template <class X, class Y>
void Pair<X,Y>::
Initialize()
{
	rep = new Pair_Rep<X,Y>;
	assert(rep != 0);
}

template <class X, class Y>
void Pair<X,Y>::
Finalize()
{
	delete rep;
}

}//end namespace ShbeebLib

#endif