#ifndef SLLIST_H
#define SLLIST_H

// An sllist is a single linked list.
// array. The item type is void * so it can store pointers
// to items of any type.

typedef struct sllist sllist;


// Creates a new empty sllist.
// If memory allocation fails, returns NULL.
sllist *sllist_new();

// Frees the memory for list. Does not free any dynamically
// allocated memory for the items in list.
void sllist_free(sllist *list);

// Returns the length of list.
size_t sllist_length(sllist *list);

// Returns the item in list in position index which
// must be less than the length of list.
void *sllist_get(sllist *list, size_t index);

// Sets the value of the item in list in position
// index which must be less than the length of list.
void sllist_put(sllist *list, size_t index, void *value);

// Appends a new item to the end of list. Returns list. If
// memory allocation fails, leaves list unchanged and
// returns NULL.
sllist *sllist_append(sllist *list, void *value);

// Removes the item from list in position index
// which must be less than the length of list. Items
// to the right of position index are shifted left.
void sllist_remove(sllist *list, size_t index);

// Inserts an item into list at position index which
// must be less than or equal to the length of list.
// Items from position index to the right are shifted right.
sllist *sllist_insert(sllist *list, size_t index, void *value);

// Returns a dynamically allocated array containing
// (the pointers to) the items in list.
void **sllist_to_array(sllist *list);

// Returns an sllist containing (the pointers to) the items
// in array of size n.
sllist *sllist_new_from_array(int n, void *array[n]);

// Iterates over the items in list calling func on each item in list.
void sllist_iterate(sllist *list, void (*func)(void *));

#endif