diff --git a/graph/memstore/iterator.go b/graph/memstore/iterator.go
index fb82a9f..68f47bb 100644
--- a/graph/memstore/iterator.go
+++ b/graph/memstore/iterator.go
@@ -34,10 +34,6 @@ type Iterator struct {
 	err    error
 }
 
-func cmp(a, b int64) int {
-	return int(a - b)
-}
-
 func NewIterator(tree *b.Tree, data string, qs *QuadStore) *Iterator {
 	iter, err := tree.SeekFirst()
 	if err != nil {
diff --git a/graph/memstore/quadstore.go b/graph/memstore/quadstore.go
index 9807c6e..fcf9753 100644
--- a/graph/memstore/quadstore.go
+++ b/graph/memstore/quadstore.go
@@ -35,6 +35,10 @@ func init() {
 	}, nil, nil)
 }
 
+func cmp(a, b int64) int {
+	return int(a - b)
+}
+
 type QuadDirectionIndex struct {
 	index [4]map[int64]*b.Tree
 }