| library; | 
 | import self as self; | 
 | import "dart:core" as core; | 
 |  | 
 | class A extends core::Object { | 
 |   synthetic constructor •() → self::A | 
 |     : super core::Object::•() | 
 |     ; | 
 | } | 
 | class B extends core::Object { | 
 |   synthetic constructor •() → self::B | 
 |     : super core::Object::•() | 
 |     ; | 
 | } | 
 | class AB1 extends self::A implements self::B { | 
 |   synthetic constructor •() → self::AB1 | 
 |     : super self::A::•() | 
 |     ; | 
 | } | 
 | class AB2 extends self::A implements self::B { | 
 |   synthetic constructor •() → self::AB2 | 
 |     : super self::A::•() | 
 |     ; | 
 | } | 
 | class BA1 extends self::B implements self::A { | 
 |   synthetic constructor •() → self::BA1 | 
 |     : super self::B::•() | 
 |     ; | 
 | } | 
 | class BA2 extends self::B implements self::A { | 
 |   synthetic constructor •() → self::BA2 | 
 |     : super self::B::•() | 
 |     ; | 
 | } | 
 | static method takeSubclassOfA(dynamic obj) → dynamic {} | 
 | static method takeSubclassOfB(dynamic obj) → dynamic {} | 
 | static method main() → dynamic { | 
 |   self::takeSubclassOfA(new self::AB1::•()); | 
 |   self::takeSubclassOfA(new self::AB2::•()); | 
 |   self::takeSubclassOfB(new self::BA1::•()); | 
 |   self::takeSubclassOfB(new self::BA2::•()); | 
 | } |