A combinator to allow pattern conjunctions

pattern-matching-conjunction.scala

// Splitter to apply two pattern matches on the same scrutinee.
case object && {
  def unapply[A](a: A) = Some((a, a))
}

// Extractor object matching first character.
object StartsWith {
  def unapply(s: String) = s.headOption
}

// Extractor object matching last character.
object EndsWith {
  def unapply(s: String) = s.reverse.headOption
}

// Extractor object matching length.
object Length {
  def unapply(s: String) = Some(s.length)
}

"foo" match {
  case StartsWith('f') && EndsWith('f') => "f.*f"
  case StartsWith('f') && EndsWith(e) && Length(3) if "aeiou".contains(e) => "f..[aeiou]"
  case _ => "_"
}