#ifndef LISTITERATOR_HH
#define LISTITERATOR_HH

/*
 * Name: Geoff Kuenning
 * Course: CS 70, Spring 2000
 * Assignment #8
 *
 * This file contains the interface for the ListIterator class.  This class
 * supports iteration over lists defined in the list.hh file.
 *
 * Normally, this file would be part of list.hh, since lists and their
 * iterators are tied so closely together.  It is provided separately
 * only because students are expected to provide their own list class.
 *
 * Requirements for the DATA class:
 *	The DATA class must support copy construction for the list
 *	class to be useful.  No other functions are required, but if
 *	DATA supports input or output, then the list class will
 *	support the corresponding functions.
 *
 * The ListIterator class provides forward-iterator access to list
 * elements.  Note that all iterators are inactivated whenever any
 * element is removed from the list.
 *
 * The following operations are supported:
 *
 * Constructors and destructors:
 *	Zero-argument construction is not allowed.  The constructor
 *	must specify a target list that is to be iterated over.  A
 *	copy constructor is also provided.
 * Operators:
 *	=		Assignment between iterators.
 *	bool		Typecast to boolean.  Returns true if the
 *			iterator currently refers to a valid list
 *			element, false if the iterator has been
 *			stepped past the end of the list.
 *	*		Access.  Returns a reference to the DATA item
 *			stored by the current list element.  Normally
 *			used as "x = *iterator;".
 *	->		Access.  Returns a pointer to the DATA item
 *			stored by the current list element.  Normally
 *			used as "x = iterator->member;".
 *	++		Incrementation.  Steps the iterator to the
 *			next list element.  Available in both prefix
 *			and postfix versions, properly implemented to
 *			return the iterator after or before
 *			incrementation, respectively.
 */

#include <stdlib.h>

#include "list.hh"

/*
 * Table of contents: the following classes are defined in this file
 */
template <typename DATA> class ListIterator;

/*
 * The ListIterator class.  See above for documentation of the public
 * functions.
 */
template <typename DATA> class ListIterator
    {
    public:
			ListIterator(const List<DATA>& source);
			ListIterator(const ListIterator& source);
			~ListIterator();
	ListIterator&	operator=(const ListIterator& source);
			operator bool() const;
					// Test for more data
	DATA&		operator*() const;
					// Provide member access
	DATA*		operator->() const;
					// Provide member access
	ListIterator<DATA>&
			operator++();	// Pre-incrementation
	ListIterator<DATA>
			operator++(int); // Post-incrementation
	void		reset();	// Reset to beginning of list

    private:
	/*
	 * Private data members
	 */
	const List<DATA>&
			target;		// Target of the iterator
	List<DATA>::Element*
			current;	// Current data element
    };

#include "listiterator.icc"

#endif // LISTITERATOR_HH