Luis Medina lu4nm3

## ex17_smart.scala
scala> new EmailAddress("@example.com") {}
<console>:15: error: illegal inheritance from sealed class EmailAddress
       new EmailAddress(""){}

## ex16_smart.scala
scala> class EvilEmailAddress(address: String) extends EmailAddress(address)
<console>:14: error: illegal inheritance from sealed class EmailAddress
       class EvilEmailAddress(address: String) extends EmailAddress(address)

## ex15_smart.scala
sealed abstract case class EmailAddress(emailAddress: String)

## ex14_smart.scala
class EvilEmailAddress(address: String) extends EmailAddress(address)

EmailClient.sendEmail(from = new EvilEmailAddress("[email protected]"), to = new EvilEmailAddress("@example.com")) {
  ...
}

## ex13_smart.scala
new EmailAddress(emailAddress) {}

## ex12_smart.scala
scala> EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
<console>:13: error: value copy is not a member of EmailAddress
       EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
       ^

## ex11_smart.scala
abstract case class EmailAddress(emailAddress: String)

## ex10_smart.scala
scala> EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
res0: scala.util.Either[String,Either[String,EmailAddress]] = Right(Left(Invalid email address))

scala> for {
  |   e1 <- EmailAddress("[email protected]")
  |   e2 <- e1.copy(emailAddress = "@example.com")
  | } yield e2
res1: scala.util.Either[String,EmailAddress] = Left(Invalid email address)

## ex9_smart.scala
case class EmailAddress(emailAddress: String) {
  def copy(emailAddress: String = emailAddress): Either[String, EmailAddress] = {
    EmailAddress(emailAddress)
  }
}

## ex8_smart.scala
scala> val emailAddress = EmailAddress("[email protected]")
emailAddress: Either[String,EmailAddress] = Right(EmailAddress([email protected]))

scala> emailAddress.map(_.copy(emailAddress = "@example.com"))
res0: scala.util.Either[String,EmailAddress] = Right(EmailAddress(@example.com))
	scala> new EmailAddress("@example.com") {}
	<console>:15: error: illegal inheritance from sealed class EmailAddress
	new EmailAddress(""){}
	scala> class EvilEmailAddress(address: String) extends EmailAddress(address)
	<console>:14: error: illegal inheritance from sealed class EmailAddress
	class EvilEmailAddress(address: String) extends EmailAddress(address)
	class EvilEmailAddress(address: String) extends EmailAddress(address)

	EmailClient.sendEmail(from = new EvilEmailAddress("[email protected]"), to = new EvilEmailAddress("@example.com")) {
	...
	}
	scala> EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
	<console>:13: error: value copy is not a member of EmailAddress
	EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
	^
	scala> EmailAddress("[email protected]").map(_.copy(emailAddress = "@example.com"))
	res0: scala.util.Either[String,Either[String,EmailAddress]] = Right(Left(Invalid email address))

	scala> for {
	\| e1 <- EmailAddress("[email protected]")
	\| e2 <- e1.copy(emailAddress = "@example.com")
	\| } yield e2
	res1: scala.util.Either[String,EmailAddress] = Left(Invalid email address)
	case class EmailAddress(emailAddress: String) {
	def copy(emailAddress: String = emailAddress): Either[String, EmailAddress] = {
	EmailAddress(emailAddress)
	}
	}
	scala> val emailAddress = EmailAddress("[email protected]")
	emailAddress: Either[String,EmailAddress] = Right(EmailAddress([email protected]))

	scala> emailAddress.map(_.copy(emailAddress = "@example.com"))
	res0: scala.util.Either[String,EmailAddress] = Right(EmailAddress(@example.com))