Terse syntax for creating an unapply

UnapplySyntax.scala

object UnapplySyntax {
  trait Unapplier[A, B] { def unapply(a: A): Option[B] }

  class <= [B, A](f: A => Option[B]) extends Unapplier[A, B] {
    def unapply(a: A): Option[B] = f(a)
  }

  object <= {
    def apply[B, A](f: A => Option[B]): B <= A = new <=(f)
  }

  implicit def unapplyConversion[B, A](f: A => Option[B]): B <= A = <=(f)


  // Using the class
  val I1 = new (Int <= String)(s => Try(s.toInt).toOption)

  // Using the apply method
  val I2 = <=((s:String) => Try(s.toInt).toOption)

  // Implicit conversion
  val I3: Int <= String = (s:String) => Try(s.toInt).toOption

}