Scala capture group using regex

Question

Let\'s say I have this code:

val string = \"one493two483three\"
val pattern = \"\"\"two(\\d+)three\"\"\".r
pattern.findAllIn(string).foreach(println)
         


        

Answer 1

Starting Scala 2.13, as an alternative to regex solutions, it's also possible to pattern match a String by unapplying a string interpolator:

"one493two483three" match { case s"${x}two${y}three" => y }
// String = "483"

Or even:

val s"${x}two${y}three" = "one493two483three"
// x: String = one493
// y: String = 483

If you expect non matching input, you can add a default pattern guard:

"one493deux483three" match {
  case s"${x}two${y}three" => y
  case _                   => "no match"
}
// String = "no match"