Example of regex extractor with pattern matching in scala.

ex-regex-pattern-matching.scala

object Parser {
  val Result = """mac: (\S+) sites: \[([^]]+)\]""".r
  def parseLine(line: String): Option[(String,Seq[String])] = line match {
    case Result(mac,sites) => Some((mac, sites.split(""",\s*""").toSeq))
    case _ => None
  }
}

val input = io.Source.fromFile("input.txt")
val lines = input.getLines()

for (opt <- lines.map(Parser.parseLine);(mac, sites) <- opt; site <- sites) { 
   println("%s %s".format(mac,site)) 
}