| library; | 
 | // | 
 | // Problems in library: | 
 | // | 
 | // pkg/front_end/testcases/class_modifiers/interface/interface_mixin_declaration.dart:5:1: Error: A mixin class can't be declared 'interface'. | 
 | // Try removing the 'interface' keyword. | 
 | // interface mixin class A {} | 
 | // ^^^^^^^^^ | 
 | // | 
 | // pkg/front_end/testcases/class_modifiers/interface/interface_mixin_declaration.dart:7:1: Error: A mixin can't be declared 'interface'. | 
 | // Try removing the 'interface' keyword. | 
 | // interface mixin B {} | 
 | // ^^^^^^^^^ | 
 | // | 
 | import self as self; | 
 | import "dart:core" as core; | 
 |  | 
 | interface mixin class A extends core::Object { | 
 |   synthetic constructor •() → self::A | 
 |     : super core::Object::•() | 
 |     ; | 
 | } | 
 | abstract class B extends core::Object /*isMixinDeclaration*/  { | 
 | } |