case insensitive pattern match in Scala - scala

Question

I want to do pattern matching in Scala but it should be case insensitive. Is there a way I can write the code without using separate 'case' clauses for lower and upper cases
//person class with first name and last name
case class Person (var fn: String, val ln: String) {
val name = fn
val lastName = ln
}
//two instances. Same last name but cases are different
val a2 = Person("Andy","Cale")
val a3 = Person("Andy","cale")
def isCale(person:Person) {
person match {
//I want that this case should be case insensitive
case Person(_,"Cale") => println("last-name Cale")
case _ => println("not Cale")
}
}
isCale(a2)
lastname Cale
//I want this to also match
isCale(a3)
not Cale
One alternative is to extract the last name and compare as follows but I am interested in finding if there is a way to do this in case itself.
def isCale(a2:A2) {
val s = a2.ln
s.toLowerCase match {
case "cale" => println("last-name Cale")
case _ => println("not Cale")
}

Answer 1

You can use a guard:
def main(args: Array[String]): Unit = {
case class Person(firstName: String, lastName: String)
val p = Person("Yuval", "Itzchakov")
p match {
case Person(_, lastName) if lastName.equalsIgnoreCase("itzchakov") =>
println(s"Last name is: $lastName")
case _ => println("Not itzchakov")
}
}
Side note - case class parameters will be attached as vals on the declared class, there's no need for the additional assignment and no need for the val/var definition on the constructor.

Answer 2

You can use an extractor:
scala> val r = "(?i:it.*ov)".r
r: scala.util.matching.Regex = (?i:it.*ov)
scala> case class Person(firstName: String, lastName: String)
defined class Person
scala> val ps = Person("Fred", "Itchikov") :: Person("Yuval", "Itzchakov") :: Nil
ps: List[Person] = List(Person(Fred,Itchikov), Person(Yuval,Itzchakov))
scala> ps collect { case Person(_, n # r()) => n }
res0: List[String] = List(Itchikov, Itzchakov)