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

typedef Test<contravariant T extends self::X> = (T?) → dynamic;
class X extends core::Object {
  synthetic constructor •() → self::X
    ;
}
static method checkme<T extends self::X>(self::checkme::T? t) → dynamic
  ;
static method main() → dynamic
  ;