text: // Copyright (c) 2012, 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.
  
  import "package:expect/expect.dart";
  
  class A {
    final x;
    const A(this.x);
    const A.named([this.x]);
    const A.named2([this.x = 2]);
  }
  
  class B extends A {
    const B(x) : super(x + 10);
    const B.named_() : super.named();
    const B.named(x) : super.named(x + 10);
    const B.named2_() : super.named2();
    const B.named2(x) : super.named2(x + 10);
  }
  
  const b1 = const B(0);
  const b2 = const B.named_();
  const b3 = const B.named(1);
  const b4 = const B.named2_();
  const b5 = const B.named2(3);
  
  main() {
    Expect.equals(10, b1.x);
    Expect.equals(null, b2.x);
    Expect.equals(11, b3.x);
    Expect.equals(2, b4.x);
    Expect.equals(13, b5.x);
  }
  