#include <itemkeyfun.h>
+/**
+ * A tuple is an array of void*
+ */
+typedef void *tuple[];
+
/**
* A tupleschema record declares the itemkeyfun functions for tuple
* items together with applicable arity and domain combinations. The
* provide the handling of the tuple columns.
*/
itemkeyfun functions;
+
/**
* This is the number of columns in a tuple.
*/
int arity;
+
/**
- * This is an array of pointers to the tuple item domains as
- * represented by their associated itemkeyfun records.
+ * This points to an array of pointers to the tuple item domains
+ * as represented by their associated itemkeyfun records.
*/
- itemkeyfun **schema;
+ itemkeyfun **columns;
} tupleschema;
/**
- * This callback function returns the hashcode of a key.
- *
- * \param this is a pointer to the itemkeyfun record from where this
- * callback got invoked
- *
- * \param key is the key to produce a hascode for
- *
- * \returns the hashcode which is a vector_index (i.e. unsigned long)
- *
- * 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 tupleitem_hashcode(itemkeyfun *this,void *key);
-
-/**
- * This callback function determines whether an item has a
- * given key or not.
+ * Create a tuples with given values.
*/
-extern int tupleitem_haskey(itemkeyfun *this,void *item,void *key);
+extern tuple *tuple_create(int arity,...);
/**
- * This callback function returns the key of an item by considering
- * the arity and schema.
+ * Create a tuples with given values.
*/
-extern void *tupleitem_itemkey(itemkeyfun *this,void *item);
+extern tupleschema *tupleschema_create(int arity,tuple *columns);
/**
- * This callback function handles a key obtained from the itemkey
- * callback function to reclaim temporary allocation.
+ * Copy the given tupleschema into a new tupleschema with some columns
+ * masked. This represents a sub-index type using the unmasked columns
+ * for indexing.
*/
-extern void tupleitem_releasekey(itemkeyfun *this,void *key);
+extern tupleschema *tupleschema_mask(tupleschema *schema,...);
/**
* The TUPLEITEMINIT macro is used for initializing a tupleschema
* of parts itemkeyfun pointers.
*/
#define TUPLEITEMINIT(arity, ... ) { \
- functions = { \
+ .functions = { \
.hashcode = tupleitem_hashcode, \
.haskey = tupleitem_haskey, \
.itemkey = tupleitem_itemkey, \