@ instance: type not found

[DmytroMitin]

  import com.github.dmytromitin.auxify.macros.{aux, instance}

  /*@aux*/ @instance
  trait Compare[T1, T2] {
    type T
    type Out = (T, T)
    def apply(a: T1, b: T2): Out
  }

  object Compare {
    type Aux[T1, T2, T0] = Compare[T1, T2] { type T = T0 }
//    def instance[T1, T2, T0](f: (T1, T2) => (T0, T0)): Aux[T1, T2, T0] = new Compare[T1, T2] {
//      override type T = T0
//      override def apply(a: T1, b: T2): Out = f(a, b)
//    }

    implicit def reverseCompare[T1, T2](implicit ev: T2 => T1): Aux[T1, T2, T1] = instance((a, b) => (a, ev(b)))
    implicit def directCompare[T1, T2](implicit ev: T1 => T2): Aux[T1, T2, T2] = instance((a, b) => (ev(a), b))
  }

  def compare[T1, T2](a: T1, b: T2)(implicit cmp: Compare[T1, T2]) = (compareImpl[cmp.T] _).tupled(cmp(a, b))
  def compareImpl[T](a: T, b: T) = a == b

  case class Foo(s: String)
  case class Bar(s: String)

  implicit def foo2bar(f: Foo): Bar = Bar(f.s)

  compare(Foo("hello"), Bar("hello"))

Warning:scalac: {
  abstract trait Compare[T1, T2] extends scala.AnyRef {
    type T;
    type Out = scala.Tuple2[T, T];
    def apply(a: T1, b: T2): Out
  };
  object Compare extends scala.AnyRef {
    def <init>() = {
      super.<init>();
      ()
    };
    def instance[T1, T2, T0$macro$1](f$macro$2: _root_.scala.Function2[T1, T2, Out]): Compare[T1, T2] {
      type T = T0$macro$1
    } = {
      final class $anon extends Compare[T1, T2] {
        def <init>() = {
          super.<init>();
          ()
        };
        override type T = T0$macro$1;
        type Out = scala.Tuple2[T, T];
        override def apply(a: T1, b: T2): Out = f$macro$2(a, b)
      };
      new $anon()
    };
    type Aux[T1, T2, T0] = Compare[T1, T2] {
      type T = T0
    };
    implicit def reverseCompare[T1, T2](implicit ev: _root_.scala.Function1[T2, T1]): Aux[T1, T2, T1] = instance(((a, b) => scala.Tuple2(a, ev(b))));
    implicit def directCompare[T1, T2](implicit ev: _root_.scala.Function1[T1, T2]): Aux[T1, T2, T2] = instance(((a, b) => scala.Tuple2(ev(a), b)))
  };
  ()
}

Error:(11, 13) not found: type Out
  /*@aux*/ @instance

[DmytroMitin]

def instance[T1, T2, T0$macro$1](f$macro$2: _root_.scala.Function2[T1, T2, Out]): Compare[T1, T2] {
      type T = T0$macro$1
    }

instead of

  def instance[T1, T2, T0](f: (T1, T2) => (T0, T0)): Aux[T1, T2, T0] = new Compare[T1, T2] {
    override type T = T0
    override def apply(a: T1, b: T2): Out = f(a, b)
  }