From 5695804e273da3a3baccf4dbc7a087578264b3c1 Mon Sep 17 00:00:00 2001
From: tserg <8017125+tserg@users.noreply.github.com>
Date: Wed, 25 Oct 2023 10:49:49 +0800
Subject: [PATCH] add comment

---
 vyper/semantics/types/subscriptable.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/vyper/semantics/types/subscriptable.py b/vyper/semantics/types/subscriptable.py
index 3faaf54509..967991ce76 100644
--- a/vyper/semantics/types/subscriptable.py
+++ b/vyper/semantics/types/subscriptable.py
@@ -295,6 +295,8 @@ def from_annotation(cls, node: vy_ast.Subscript) -> "DArrayT":
 
         value_type = type_from_annotation(node.slice.value.elements[0])
         if not value_type._as_darray:
+            # TODO: this is currently not reachable because all instantiable types are set to True
+            #       and non-instantiable types like events are caught by `type_from_annotation`
             raise StructureException(f"Arrays of {value_type} are not allowed", node)
 
         return cls(value_type, max_length)