viewvc/ccscs20/Iterator.hpp

// Iterator
//
// Douglas Thrift
//
// $Id$

#ifndef _Iterator_hpp_
#define _Iterator_hpp_

#include "NullNode.hpp"

template<typename Type>
class DoublyLinkedList;

template<typename Type>
class Iterator
{
private:
        NullNode<Type>* front;
        NullNode<Type>* back;
        NullNode<Type>* here;
        Iterator(NullNode<Type>* front, NullNode<Type>* back, bool forward = true) : front(front), back(back) { here = forward ? front->getNext() : back->getPrevious(); }
public:
        bool next(void) { return here->getNext() != back; }
        bool previous(void) { return here->getPrevious() != front; }
        Iterator<Type>& operator++() { here = here->getNext(); return *this; }
        Iterator<Type> operator++(int);
        Iterator<Type>& operator--() { here = here->getPrevious(); return *this; }
        Iterator<Type> operator--(int);
        const Type& operator*() { return here->getValue(); }
// friends:
        friend class DoublyLinkedList<Type>;
};

template<typename Type>
Iterator<Type> Iterator<Type>::operator++(int)
{
        Iterator itor(*this);

        ++*this;
        
        return itor;
}

template<typename Type>
Iterator<Type> Iterator<Type>::operator--(int)
{
        Iterator itor(*this);

        --*this;

        return itor;
}

#endif // _Iterator_hpp_
Revision:	7
Committed:	2004-05-14T00:13:01-07:00 (21 years, 1 month ago) by Douglas Thrift
File size:	1171 byte(s)
Log Message:	Eraser!
#	User	Rev	Content
1	Douglas Thrift	1	// Iterator
2			//
3			// Douglas Thrift
4			//
5			// $Id$
6
7			#ifndef _Iterator_hpp_
8			#define _Iterator_hpp_
9
10	Douglas Thrift	7	#include "NullNode.hpp"
11
12	Douglas Thrift	1	template<typename Type>
13	Douglas Thrift	7	class DoublyLinkedList;
14
15			template<typename Type>
16	Douglas Thrift	1	class Iterator
17			{
18			private:
19	Douglas Thrift	7	NullNode<Type>* front;
20			NullNode<Type>* back;
21			NullNode<Type>* here;
22			Iterator(NullNode<Type>* front, NullNode<Type>* back, bool forward = true) : front(front), back(back) { here = forward ? front->getNext() : back->getPrevious(); }
23	Douglas Thrift	1	public:
24	Douglas Thrift	7	bool next(void) { return here->getNext() != back; }
25			bool previous(void) { return here->getPrevious() != front; }
26			Iterator<Type>& operator++() { here = here->getNext(); return *this; }
27	Douglas Thrift	1	Iterator<Type> operator++(int);
28	Douglas Thrift	7	Iterator<Type>& operator--() { here = here->getPrevious(); return *this; }
29	Douglas Thrift	1	Iterator<Type> operator--(int);
30	Douglas Thrift	7	const Type& operator*() { return here->getValue(); }
31			// friends:
32			friend class DoublyLinkedList<Type>;
33	Douglas Thrift	1	};
34
35	Douglas Thrift	7	template<typename Type>
36			Iterator<Type> Iterator<Type>::operator++(int)
37			{
38			Iterator itor(*this);
39
40			++*this;
41
42			return itor;
43			}
44
45			template<typename Type>
46			Iterator<Type> Iterator<Type>::operator--(int)
47			{
48			Iterator itor(*this);
49
50			--*this;
51
52			return itor;
53			}
54
55	Douglas Thrift	1	#endif // _Iterator_hpp_