pkg/front_end/testcases/general/issue47728_1.dart

// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart=2.12

typedef A = Function()?;

class B {}

class C = A with B;

main() {}