library;
import self as self;
import "dart:core" as core;

class B<X extends core::Object = dynamic, Y extends core::Object = dynamic> extends core::Object {
  synthetic constructor •() → void
    : super core::Object::•()
    ;
}
class C<X extends core::Object = dynamic, Y extends core::Object = dynamic> extends core::Object {
  synthetic constructor •() → void
    : super core::Object::•()
    ;
}
class D<X extends self::B<self::D::X, self::D::Y> = self::B<dynamic, dynamic>, Y extends self::C<self::D::X, self::D::Y> = self::C<dynamic, dynamic>, Z extends (self::D::Y) → self::D::X = (core::Null) → self::B<dynamic, dynamic>, W extends core::num = core::num> extends core::Object {
  synthetic constructor •() → void
    : super core::Object::•()
    ;
}
static method main() → dynamic {
  self::D<self::B<dynamic, dynamic>, self::C<dynamic, dynamic>, (core::Null) → self::B<dynamic, dynamic>, core::num> d;
}