import util.matching._




object Test {

  def main(args: Array[String]): Unit = {
    replacementMatching
    groupsMatching
  }

  def replacementMatching: Unit = {
    val regex = """\$\{(.+?)\}""".r
    val replaced = regex.replaceAllIn("Replacing: ${main}. And another method: ${foo}.",
        (m: util.matching.Regex.Match) => {
      val identifier = m.group(1)
      identifier
    })
    assert(replaced == "Replacing: main. And another method: foo.")

    val regex3 = """\$\{(.+?)\}""".r
    val replaced3 = regex3.replaceSomeIn("Replacing: ${main}. And another: ${foo}.", (m: util.matching.Regex.Match) => {
      val id = m.group(1)
      if (id.startsWith("m")) Some(id) else None
    })
    assert(replaced3 == "Replacing: main. And another: ${foo}.")
  }

  def groupsMatching: Unit = {
    val Date = """(\d+)/(\d+)/(\d+)""".r
    for (Regex.Groups(a, b, c) <- Date findFirstMatchIn "1/1/2001 marks the start of the millenium. 31/12/2000 doesn't.") {
      assert(a == "1")
      assert(b == "1")
      assert(c == "2001")
    }
    for (Regex.Groups(a, b, c) <- (Date findAllIn "1/1/2001 marks the start of the millenium. 31/12/2000 doesn't.").matchData) {
      assert(a == "1" || a == "31")
      assert(b == "1" || b == "12")
      assert(c == "2001" || c == "2000")
    }
  }

}