gistfile1.scala

  object stuff {
    import scala.util.parsing.combinator._

    class Parser extends RegexParsers {
      
      def parseTop(s: String): Stuff = parse(top(""), s) match {
        case Success(value, _) => value
        case _ => throw new RuntimeException("...")
      }

      def top(indent:String): Parser[Stuff] =
        single(indent) | top(indent + " ")

      def single(indent:String): Parser[Stuff] =
        (indent + "a") ^^ { s => Stuff(s.length) }

      override def skipWhitespace = false
    }

    case class Stuff(i: Int)
  }

  println((new stuff.Parser).parseTop("  a").i)