| // Copyright (c) 2022, 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 The semantics of such an enum declaration, E, is defined as |
| /// introducing a (semantic) class, C, just like a similar class declaration. |
| /// ... |
| /// Superclass: The superclass of C is an implementation-specific built-in class |
| /// EnumImpl, with the mixins declared by E applied. (The EnumImpl class may be |
| /// the Enum class itself or it may be another class which extends or implements |
| /// Enum, but as seen from a non-platform library the interface of EnumImpl is |
| /// the same as that of Enum, and its methods work as specified for Enum ) |
| /// |
| /// If E is declared as enum Name with Mixin1, Mixin2 … then the superclass of C |
| /// is the mixin application EnumImpl with Mixin1, Mixin2. |
| /// It’s a compile-time error if such a mixin application introduces any |
| /// instance variables. We need to be able to call an implementation specific |
| /// superclass const constructor of Enum, and a mixin application of a mixin |
| /// with a field does not make its forwarding constructor const. Currently |
| /// that’s the only restriction, but if we add further restrictions on mixin |
| /// applications having const forwarding constructors, those should also apply |
| /// here. |
| /// |
| /// @description Check that it’s a compile-time error if such a mixin |
| /// application introduces late final variables. |
| /// @author sgrekhov@unipro.ru |
| |
| // SharedOptions=--enable-experiment=enhanced-enums |
| |
| mixin M1 on Object { |
| int mixedInMethod1(int v) => v; |
| } |
| |
| mixin M2 on Enum { |
| late final int i2 = 1; |
| int mixedInMethod2(int i) => index + i; |
| } |
| |
| enum E with M1, M2 { |
| // ^^ |
| // [analyzer] unspecified |
| // [cfe] unspecified |
| e1, |
| e2, |
| e3; |
| } |
| |
| main() { |
| E.e1; |
| } |