Pattern match for variable in scope (Scala)

Question

In the following code

val x = 5
val y = 4 match {
  case x => true
  case _ => false
}

the value y is true. Scala interp

Answer 1

Invoking the least astonishment principle, I will simply do:

val x = 5
val y = 4 match {
  case z if z == x => true
  case _ => false
}