|  | library; | 
|  | import self as self; | 
|  | import "dart:core" as core; | 
|  |  | 
|  | abstract class A extends core::Object { | 
|  | synthetic constructor •() → self::A | 
|  | ; | 
|  | } | 
|  | class B extends core::Object { | 
|  | final field self::A a; | 
|  | external constructor •(self::A a) → self::B; | 
|  | } | 
|  | class C extends core::Object { | 
|  | final field self::A a1; | 
|  | final field self::A a2; | 
|  | external constructor •() → self::C; | 
|  | constructor named(self::A a1, self::A a2) → self::C | 
|  | ; | 
|  | } | 
|  | class D extends core::Object { | 
|  | final field self::A a1; | 
|  | final field self::A a2; | 
|  | external constructor •() → self::D; | 
|  | constructor named(self::A a1) → self::D | 
|  | ; | 
|  | } | 
|  | class E extends core::Object { | 
|  | final field self::A a1; | 
|  | final field self::A a2; | 
|  | constructor •(self::A a2) → self::E | 
|  | ; | 
|  | external constructor named() → self::E; | 
|  | } | 
|  | class F extends core::Object { | 
|  | final field self::A a1; | 
|  | final field self::A a2; | 
|  | constructor •(self::A a1, self::A a2) → self::F | 
|  | ; | 
|  | external constructor named() → self::F; | 
|  | } |