// DllIterator.h  doubly linked list iterator class for Encoder
//	an iterator of this type operates on the Encoder dll

#ifndef DLL_ITERATOR     
#define DLL_ITERATOR     

#include <string>
#include "TNode.h" 
template <class T>

// doubly linked list const iterator
class DllIterator {

  private:
    TNode<T> *curr;   // points to current node

  public:
    // initializes curr to currIn
    DllIterator(TNode<T> *currIn = NULL);

    // returns a pointer to an element of type T
    const TNode<T> * operator->() const;

    // dereference curr, returns element of type T
    const T &operator*() const;

    // pre-increment operator
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator &operator++();

    // post-increment operator
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator++(int);

    // pre-decrement operator
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator &operator--();

    // post-decrement operator
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator--(int);

    // for iterator math
    // for example it = it + 4;
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator+(const int &);

    // for iterator math
    // for example it = it - 4;
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator-(const int &);

    // for iterator math
    // for example it -= 4;
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator-=(const int &);

    // for iterator math
    // for example it += 4;
    // THROWS OutOfBounds EXCEPTION if you walk off the dll
    DllIterator operator+=(const int &);

    // equality operator
    bool operator==(const DllIterator &other);

    // inequality operator
    bool operator!=(const DllIterator &other);

  private:

    // you may put any private member functions here
};
    
#endif // DLL_ITERATOR