|  | // 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. | 
|  |  | 
|  | // @dart = 2.9 | 
|  |  | 
|  | class A { | 
|  | const A(a); | 
|  | const A.named({a: 42}); | 
|  | const A.optional([a]); | 
|  | } | 
|  |  | 
|  | main() { | 
|  | const A(1); | 
|  | const A(); | 
|  | //     ^^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.NOT_ENOUGH_POSITIONAL_ARGUMENTS | 
|  | // [cfe] Too few positional arguments: 1 required, 0 given. | 
|  | const A(1, 2); | 
|  | //         ^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.EXTRA_POSITIONAL_ARGUMENTS | 
|  | //     ^^^^^^ | 
|  | // [cfe] Too many positional arguments: 1 allowed, but 2 found. | 
|  | const A.named(); | 
|  | const A.named(b: 1); | 
|  | //            ^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.UNDEFINED_NAMED_PARAMETER | 
|  | // [cfe] No named parameter with the name 'b'. | 
|  | const A.named(a: 1, a: 2); | 
|  | //                  ^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.DUPLICATE_NAMED_ARGUMENT | 
|  | // [cfe] Duplicated named argument 'a'. | 
|  | const A.named(a: 1, b: 2); | 
|  | //                  ^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.UNDEFINED_NAMED_PARAMETER | 
|  | // [cfe] No named parameter with the name 'b'. | 
|  | const A.optional(); | 
|  | const A.optional(42); | 
|  | const A.optional(42, 54); | 
|  | //                   ^^ | 
|  | // [analyzer] COMPILE_TIME_ERROR.EXTRA_POSITIONAL_ARGUMENTS | 
|  | //              ^^^^^^^^ | 
|  | // [cfe] Too many positional arguments: 1 allowed, but 2 found. | 
|  | } |