These methods perform transformations on their input. They'll be tied together in different ways separately. Look for the blog post at blog.jessitron.com.

transformers

// from https://github.com/jessitron/BlogCode/blob/master/optionAsFlow.scala

object transformers {

  def openFile(n: String) : Option[java.io.File] = {
    val f = new java.io.File(n) // catch IOException
    if (f.exists)
      Some(f)
    else
      None    
  }

  def readFirstLine (f : java.io.File) : Option[String] = {
    val source = io.Source.fromFile(f)
    try {
      if (!source.hasNext) 
        None 
      else 
        Some(source.getLines.next)
    } finally {
      source.close
    }
  }

  def parseLine(line : String) : Option[SecretMessage] = {
    val ExpectedFormat = "The secret message is '(.*)'".r
    line match {
      case ExpectedFormat(secretMessage) => Some(SecretMessage(secretMessage))
      case _ => None
    }
  }
}