diff --git a/slices/slices.go b/slices/slices.go
index 7fa4bdf..08dcfa1 100644
--- a/slices/slices.go
+++ b/slices/slices.go
@@ -39,9 +39,14 @@ func (ps *PtrSlice) Val() interface{} {
 	return ps.current
 }
 
-func (ps *PtrSlice) Incr() {
-	ps.idx++
-	ps.current = ps.slice.Index(ps.idx).Interface()
+func (ps *PtrSlice) Next() {
+	if ps.idx < ps.length-1 {
+		ps.idx++
+		ps.current = ps.slice.Index(ps.idx).Interface()
+	} else if ps.idx == ps.length-1 {
+		ps.idx++
+		ps.current = nil
+	}
 }
 
 func (ps *PtrSlice) Len() int {