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

class D<X extends () → void> extends core::Object {
  constructor _() → self::D<self::D::X>
    ;
  static factory foo<X extends () → void>() → self::D<self::D::foo::X>
    ;
}
static method main() → dynamic
  ;