-/**
- * This callback function returns the hashcode of a key. The hashcode
- * is used for indexing into the backing vector for finding the an
- * item via its key. The same key must map consistently to the same
- * hashcode while the hashtable contains an item with that key.
- * Different keys map map to the same hashcode, in which case the
- * vector placement is made at the first empty or hole slot following
- * the hashcode index.
- */
-extern unsigned long integeritem_hashcode(itemkeyfun *this,void *key);
-
-/**
- * This callback function determines whether an item has a
- * given key or not.
- */
-extern int integeritem_haskey(itemkeyfun *this,void *item,void *key);
-
-/**
- * This callback function returns the key of an item by considering
- * the arity and schema.
- */
-extern void *integeritem_itemkey(itemkeyfun *this,void *item);
-
-/**
- * This callback function handles a key obtained from the itemkey
- * callback function to reclaim temporary allocation.
- */
-extern void integeritem_releasekey(itemkeyfun *this,void *key);
-