advanced-scala-pattern-matching-code8.scala

val five = 5
five match {
  case v if v > 5 => ???
  case v if v == 5 => ???
  case v if v < 5 => ???
}
// more practical example
final case class FeeInquiry(user: UserId, amount: BigDecimal, currency: Currency)

val requestedFee: Option[FeeInquiry] = ???

requestedFee match {
  case Some(FeeInquiry(user, amount, currency) if currency === Currency.USD => 
            Right(amount)
  case Some(FeeInquiry(user, amount, currency) if currency === Currency.__ => 
            Left("We can't accept other than USD")
  case None => Right(BigDecimal(0))
}