/*
 *
 * Copyright (c) 1995
 * Knowledge Science Institute, University of Calgary
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  The Knowledge Science Institute makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 */

#ifndef MREF2_H
#define MREF2_H

#ifndef MERROR_H
#include <MError.h>
#endif

#ifndef MDEBUG_H
#include <MDebug.h>
#endif

#define NOTHING

template <class T>
class Ref2
  {
  public:
    DECL_EXCEPT_CLASS(NOTHING,DefConstructorCalled,ErrorMsgException,"Illegal operation: Default Constructor Called");
    Ref2(const T &s)	{KillData = true;
			 t = s.clone();}
    Ref2(T *s, bool ownIt=false) {MASSERT(s); KillData = ownIt; t = s;}
    Ref2(const Ref2<T> &r)
			//{KillData = true;
			// t = (r.t?r.t->clone():NULL);}
			{KillData = r.KillData;
			 t = (r.t?(KillData?r.t->clone():r.t):NULL);}
    Ref2()		{throw DefConstructorCalled();}
    ~Ref2()		{if (t && KillData) delete t;}

    Ref2<T>& operator=(const Ref2<T>& r) {
			 if (t && KillData) delete t;
			 KillData = true;
			 t = (r.t?r.t->clone():NULL);
			 return *this; }
    T* operator->() const
			{return t;}
    int operator< (const Ref2<T>& r) const
			{return t?(r.t?(*t) < (*r.t):false):true;}
    operator T&() const	{return *t;}
    operator T*() const	{return t;}
    T& operator*() const
			{return *t;}
    ostream& printOn(ostream& o) const
			{o << *t; return o;}
  protected:
    T *t;
  private:
    bool KillData;
  };

#endif