GroupBy, ForEach and Case

  case class Person(name : String, site : String)

  val team = List(
      Person("Moni", "M"), Person("Anna", "M"), 
      Person("Hannes", "N"), Person("Horst", "N"));
  
  val sites = team.groupBy(_.site);
  
  sites.foreach {
    case (site, persons) => 
      println(site + ": " + persons.map(_.name).mkString(", "));
  }

  sites.foreach {
    siteAndPersons =>
      println(siteAndPersons._1 + ": " + siteAndPersons._2.map(_.name).mkString(", "));
  }