diff --git a/interpreter/src/objects.rs b/interpreter/src/objects.rs
index 6c8ccc2..69919f7 100644
--- a/interpreter/src/objects.rs
+++ b/interpreter/src/objects.rs
@@ -174,6 +174,7 @@ pub enum Value {
     Null,
 }
 
+#[derive(Copy, Debug)]
 pub enum ValueType {
     List,
     Map,