gistfile1.scala

object Main {
  def writeFile(fileName: String) {
    val letter = new FileWriter(s"${System.getenv("USERPROFILE")}/${fileName}.txt")
    try {
      Stream.continually(readLine()).takeWhile(_ != ".").map(_ + "\n").foreach(letter.write)
    } finally {
      letter.close()
    }
  }
 
  def main(args: Array[String]) {
    writeFile(args(0))
  }
}

Scala: write file