| // Copyright (c) 2019, 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. |
| |
| /// @assertion A generic type alias is a declaration [D] of one of the following |
| /// forms: |
| /// ... |
| /// m typedef S? id<X1 extends B1, . . . , Xs extends Bs>( |
| /// T1 p1, . . . , Tn pn, [Tn+1 pn+1, . . . , Tn+k pn+k]); |
| /// ... |
| /// where [m] is derived from metadata, [T] is a type, and [S?] is a type or the |
| /// empty string. Let [S0] be [S?] if it is a type, otherwise let [S0] be |
| /// [dynamic]. The associated type of [D], call it [F], is, respectively: |
| /// ... |
| /// S0 Function(T1, . . . , Tn, [Tn+1, . . . , Tn+k]) |
| /// ... |
| /// @description Checks that function generic type alias declaration can have |
| /// optional position arguments. |
| /// @author iarkh@unipro.ru |
| |
| |
| import "../../Utils/expect.dart"; |
| |
| typedef int test1<T extends num>(int x, [int y]); |
| |
| int t1<T extends int>(int x, [int y = 0]) { |
| return y == 0 ? x : y; |
| } |
| |
| main() { |
| test1 res = t1; |
| Expect.equals(14, res(1, 14)); |
| Expect.equals(1, res(1)); |
| } |
