| // Copyright (c) 2018, 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. | 
 |  | 
 | // dart2jsOptions=--strong | 
 |  | 
 | import 'package:expect/expect.dart'; | 
 |  | 
 | abstract class A { | 
 |   m({a, b}); | 
 | } | 
 |  | 
 | class B implements A { | 
 |   noSuchMethod(Invocation i) { | 
 |     return '${i.namedArguments[#a]},${i.namedArguments[#b]}'; | 
 |   } | 
 | } | 
 |  | 
 | void main() { | 
 |   A x = new B(); | 
 |   Expect.equals('3,4', x.m(a: 3, b: 4)); | 
 |   Expect.equals('3,4', x.m(b: 4, a: 3)); | 
 | } |