diff --git a/vexflow/vexflow.d.ts b/vexflow/vexflow.d.ts
index 5f450190a3..f44fb7868a 100644
--- a/vexflow/vexflow.d.ts
+++ b/vexflow/vexflow.d.ts
@@ -346,7 +346,7 @@ declare module Vex {
         }
         
         export module Curve {
-            enum Position {NEAR_HEAD, NEAR_TOP}
+            const enum Position {NEAR_HEAD, NEAR_TOP}
         }
         
         class Curve {