aggstate_set_extra DatumGetSkipListP ensure_same_skiplist_subtype PG_GETARG_SKIPLIST_P PG_RETURN_SKIPLIST_P skiplist_headval skiplist_make skiplist_splice skiplist_temporal_values skiplist_values SkipListPGetDatum

skiplist_headval() void * skiplist_headval ( SkipList *  list ) Return the value at the head of the skiplist.