diff --git a/packages/vue-language-core/src/generators/template.ts b/packages/vue-language-core/src/generators/template.ts
index e0d01b6fb..73c44487f 100644
--- a/packages/vue-language-core/src/generators/template.ts
+++ b/packages/vue-language-core/src/generators/template.ts
@@ -1023,7 +1023,7 @@ export function generate(
 					);
 				}
 				else {
-					codeGen.addText(`undefined`);
+					codeGen.addText(`() => {}`);
 				}
 			}
 		}