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

class C extends core::Object {
  field core::int? _#C#x;
  synthetic constructor •() → self::C
    ;
  get x() → core::int;
  set x(covariant-by-declaration core::int x#param) → void;
}
class D extends self::C {
  synthetic constructor •() → self::D
    ;
  set x(covariant-by-declaration core::num value) → void
    ;
}
static method main() → dynamic
  ;