/*------------------------------------------------------------------*/
/* list.h                                                           */
/*------------------------------------------------------------------*/

#ifndef LIST_INCLUDED
#define LIST_INCLUDED

typedef struct List *List_T;
typedef struct ListIter *ListIter_T;
typedef struct ListIterR *ListIterR_T;

extern List_T List_new();
/* Return a new List_T. */

extern void List_free(List_T oList);
/* Free oList. */

extern unsigned long List_length(List_T oList);
/* Return the number of items in oList. */

extern void *List_getFirst(List_T oList);
/* Return the first item in oList.
   Checked runtime error: oList is empty. */

extern void *List_getLast(List_T oList);
/* Return the last item in oList.
   Checked runtime error: oList is empty. */

extern void List_addFirst(List_T oList, void *pvItem);
/* Add pvItem to the beginning of oList. */

extern void List_addLast(List_T oList, void *pvItem);
/* Add pvItem to the end of oList. */

extern void List_removeFirst(List_T oList);
/* Remove the first item of oList.
   Checked runtime error: oList is empty. */

extern void List_removeLast(List_T oList);
/* Remove the last item of oList.
   Checked runtime error: oList is empty. */

extern void List_map(List_T oList, 
   void (*pfApply)(void **ppvItem, void *pvExtra),
   void *pvExtra);
/* Call (*pfApply)(&pvItem, pvExtra) for each item pvItem of oList. 
   Checked runtime error: pfApply is null. */

extern void List_toArray(List_T oList, void **ppvArray);
/* Fill array ppvArray with all items of oList.  ppvArray must
   be large enough to hold all items.
   Checked runtime error: ppvArray is NULL. */

extern ListIter_T ListIter_new(List_T oList);
/* Return a new ListIter_T that can iterate over oList from
   front to back. */
 
extern void ListIter_free(ListIter_T oListIter); 
/* Free oListIter. */

extern int ListIter_hasNext(ListIter_T oListIter);
/* Return 1 (TRUE) iff the List_T over which oListIter is 
   iterating has a next item. */

extern void *ListIter_next(ListIter_T oListIter);
/* Return the next item of the List_T over which oListIter
   is iterating. */

extern ListIterR_T ListIterR_new(List_T oList); 
/* Return a new ListIterR_T that can iterate over oList from
   back to front. */

extern void ListIterR_free(ListIterR_T oListIterR); 
/* Free oListIterR. */

extern int ListIterR_hasPrevious(ListIterR_T oListIterR);
/* Return 1 (TRUE) iff the List_T over which oListIterR 
   is iterating has a previous item. */

extern void *ListIterR_previous(ListIterR_T oListIterR);
/* Return the previous item of the List_T over which oListIterR
   is iterating. */

/* 
   Checked runtime errors:
   oList is NULL.
   oListIter is NULL.
   oListIterR is NULL.
*/

#endif