diff --git a/src/vim9script.c b/src/vim9script.c
index 3035889..cdacf0b 100644
--- a/src/vim9script.c
+++ b/src/vim9script.c
@@ -1127,6 +1127,7 @@
     "null_dict",
     "null_function",
     "null_list",
+    "null_tuple",
     "null_partial",
     "null_string",
     "null_channel",