alternative.scala

// Notice we're just extending our prior notion.
trait Alternative[F[_]] {
  // Kind of like true, or 1
  def pure[A](x: A): F[A]

  // Kind of like boolean AND, or multiplication
  def product[A, B](fa: F[A], fb: F[B]): F[(A, B)]

  // Kind of like false, or 0
  def empty[A]: F[A]

  // Kind of like boolean XOR, or addition
  // Named this way for Reasons™
  def combineK[A](x: F[A], y: F[A]): F[A]
}