Fixes #1255. Use nullable type parameter for type check
diff --git a/LanguageFeatures/Super-parameters/type_inference_A03_t02.dart b/LanguageFeatures/Super-parameters/type_inference_A03_t02.dart
index 324fa19..6c2185c 100644
--- a/LanguageFeatures/Super-parameters/type_inference_A03_t02.dart
+++ b/LanguageFeatures/Super-parameters/type_inference_A03_t02.dart
@@ -18,7 +18,7 @@
 
 import "../../Utils/expect.dart";
 
-test<T>(T t) {}
+test<T>(T? t) {}
 
 class S<T> {
   final f1;