| library; | 
 | // | 
 | // Problems in library: | 
 | // | 
 | // pkg/front_end/testcases/class_modifiers/interface/outside_library/main.dart:7:37: Error: The class 'A' can't be extended outside of its library because it's an interface class. | 
 | // class ExtendsInterfaceClass extends A {} | 
 | //                                     ^ | 
 | // | 
 | import self as self; | 
 | import "main_lib.dart" as mai; | 
 | import "dart:core" as core; | 
 |  | 
 | import "org-dartlang-testcase:///main_lib.dart"; | 
 |  | 
 | class ExtendsInterfaceClass extends mai::A { | 
 |   synthetic constructor •() → self::ExtendsInterfaceClass | 
 |     : super mai::A::•() | 
 |     ; | 
 | } | 
 | abstract class MixinOnA extends mai::A /*isMixinDeclaration*/  { | 
 | } | 
 | abstract class MixinOnAM extends self::_MixinOnAM&A&B /*isMixinDeclaration*/  { | 
 | } | 
 | abstract class _MixinOnAM&A&B extends core::Object implements mai::A, mai::B /*isAnonymousMixin*/  { | 
 |   synthetic constructor •() → self::_MixinOnAM&A&B | 
 |     : super core::Object::•() | 
 |     ; | 
 | } |