diff --git a/ndb.go b/ndb.go
index e71c5d7..6fe6e8d 100644
--- a/ndb.go
+++ b/ndb.go
@@ -206,7 +206,7 @@ func (e *Encoder) Encode(v interface{}) error {
 	return Switch(e, val) 
 }
 
-func Switch(e *Encoder, v reflect.Value) error {
+func Switch(e *Encoder, val reflect.Value) error {
 	switch val.Kind() {
 	case reflect.Slice:
 		return e.encodeSlice(val)