Example of `lazy val` inside `implicit class`

gistfile1.scala

// `lazy val` inside `implicit class`

implicit class RichStream[T](s: Stream[T]) {
  lazy val circular: Stream[T] =
    s #::: circular
}

// in order to make this work with `extends AnyVal`, you have to make the
// lazy val local, as follows:

implicit class RichStream[T](private val s: Stream[T]) extends AnyVal {
  def circular: Stream[T] = {
    lazy val result: Stream[T] = s #::: result
    result
  }
}