Chapter2 続き。.scala

    // For
    for (book <- booklist) {
      println(book)
    }
    // Using Filter
    for (book <- booklist if book.contains("Scala")) {
      println(s"Filter $book")
    }
    // Variable binding in for
    for {book <- booklist
         bookVal = book.toUpperCase}
      println(s"$bookVal : $book")

    // Yield
    var scalabooks = for {
      book <- booklist
      if book.contains("a")
    } yield book
    for (sb <- scalabooks)
      println("Yield aBook: " + sb)

    // Try/finally
    try {
      throw new Exception("something")
    } catch {
      case e: java.io.IOException => println("IOE")
      case n: NullPointerException => println("nullp")
      case t: Exception => println("exp")
    }finally {
      println("This will always be printed.")
    }

    // try parseInt
    println(
      try {
        Integer.parseInt("dog")
      } catch { case _ : Throwable => 0 }
    )
    println(
      try {
        Integer.parseInt("44")
      } catch { case _ : Throwable => 0 }
    )

    // Match
    println(
      44 match {
        case 44 => true
        case _ => false
      }
    )
    println(
      "David" match {
        case "Elwood" => 77
        case "David" => 45
        case _ => 0
      }
    )