Typeconstructor equivalence

tceq.scala

object tc {
  sealed trait =::=[F[_], G[_]] {
    def apply[A](f: F[A]): G[A]
  }
  object =::= {
    implicit def idFunctors[F[_]]: F =::= F = new =::=[F, F] {
      def apply[A](f: F[A]): F[A] = f
    }
  }
  
  type Id[A] = A
  type SomeotherId[A] = A
  implicitly[Id =::= SomeotherId]
}