diff --git a/src/core/interface.scala b/src/core/interface.scala
index 161caaf8..9a85a1bc 100644
--- a/src/core/interface.scala
+++ b/src/core/interface.scala
@@ -85,7 +85,7 @@ object SealedTrait:
                 val annotations: IArray[Any],
                 val typeAnnotations: IArray[Any],
                 val isObject: Boolean,
-                index: Int,
+                val index: Int,
                 callByNeed: CallByNeed[Typeclass[SType]],
                 isType: Type => Boolean,
                 asType: Type => SType & Type
@@ -109,4 +109,4 @@ final class CallByNeed[+A](private[this] var eval: () => A) extends Serializable
   lazy val value: A =
     val result = eval()
     eval = null
-    result
\ No newline at end of file
+    result