library /*isNonNullableByDefault*/;
import self as self;
import "dart:core" as core;
import "dart:async" as asy;

import "dart:async";

class B<Y extends core::Object? = dynamic> extends core::Object {
  synthetic constructor •() → self::B<self::B::Y%>
    ;
  method bar(generic-covariant-impl asy::FutureOr<self::B::Y%> y) → dynamic
    ;
}
class A<X extends core::Object? = dynamic> extends core::Object {
  generic-covariant-impl final field self::B<self::A::X%> b;
  synthetic constructor •() → self::A<self::A::X%>
    ;
  method foo([generic-covariant-impl asy::FutureOr<self::A::X%>? x]) → dynamic
    ;
}
class C<T extends core::Object? = dynamic> extends core::Object {
  synthetic constructor •() → self::C<self::C::T%>
    ;
  method baz<generic-covariant-impl X extends asy::FutureOr<self::C::T%> = asy::FutureOr<self::C::T%>>(generic-covariant-impl asy::FutureOr<self::C::T%> x) → asy::FutureOr<self::C::T%>
    ;
}
class D<T extends core::Object? = dynamic> extends self::C<self::D::T%> {
  synthetic constructor •() → self::D<self::D::T%>
    ;
  method baz<generic-covariant-impl X extends asy::FutureOr<self::D::T%> = asy::FutureOr<self::D::T%>>(generic-covariant-impl asy::FutureOr<self::D::T%> x) → asy::FutureOr<self::D::T%>
    ;
}
static method main() → dynamic
  ;