|  | library; | 
|  | // | 
|  | // Problems in library: | 
|  | // | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:7:1: Error: The 'class-modifiers' language feature is disabled for this library. | 
|  | // Try removing the `@dart=` annotation or setting the language version to 3.0 or higher. | 
|  | // base class A {} | 
|  | // ^^^^ | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:5:1: Context: This is the annotation that opts out this library from the 'class-modifiers' language feature. | 
|  | // // @dart=2.19 | 
|  | // ^^^^^^^^^^^^^ | 
|  | // | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:9:10: Error: The 'class-modifiers' language feature is disabled for this library. | 
|  | // Try removing the `@dart=` annotation or setting the language version to 3.0 or higher. | 
|  | // abstract base class B {} | 
|  | //          ^^^^ | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:5:1: Context: This is the annotation that opts out this library from the 'class-modifiers' language feature. | 
|  | // // @dart=2.19 | 
|  | // ^^^^^^^^^^^^^ | 
|  | // | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:11:1: Error: The 'class-modifiers' language feature is disabled for this library. | 
|  | // Try removing the `@dart=` annotation or setting the language version to 3.0 or higher. | 
|  | // base mixin M {} | 
|  | // ^^^^ | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:5:1: Context: This is the annotation that opts out this library from the 'class-modifiers' language feature. | 
|  | // // @dart=2.19 | 
|  | // ^^^^^^^^^^^^^ | 
|  | // | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:12:1: Error: The 'class-modifiers' language feature is disabled for this library. | 
|  | // Try removing the `@dart=` annotation or setting the language version to 3.0 or higher. | 
|  | // base class C = Object with M; | 
|  | // ^^^^ | 
|  | // pkg/front_end/testcases/general/base_class_declaration.dart:5:1: Context: This is the annotation that opts out this library from the 'class-modifiers' language feature. | 
|  | // // @dart=2.19 | 
|  | // ^^^^^^^^^^^^^ | 
|  | // | 
|  | import self as self; | 
|  | import "dart:core" as core; | 
|  |  | 
|  | class A extends core::Object { | 
|  | synthetic constructor •() → self::A | 
|  | ; | 
|  | } | 
|  | abstract class B extends core::Object { | 
|  | synthetic constructor •() → self::B | 
|  | ; | 
|  | } | 
|  | abstract class M extends core::Object /*isMixinDeclaration*/  { | 
|  | } | 
|  | class C = core::Object with self::M /*hasConstConstructor*/  { | 
|  | const synthetic constructor •() → self::C | 
|  | : super core::Object::•() | 
|  | ; | 
|  | } |