parboiled cached actions?

MyParser.scala

package lp.windhaml

import org.parboiled.scala._
import org.parboiled.support._
import org.parboiled.support.ParseTreeUtils
import scala.io.Source

class MyParser extends Parser {
    var count = 1
    def all = rule {
        oneOrMore(myrule)
    }
    def myrule = rule {
        count += 1
        println("************ myrule: " + count)
        drule(count, "a")
    }
    private def drule(count: Int, str: String) = {
        println("############## count: " + count + ", str: " + str)
        nTimes(count, str)
    }
}

object MyParser {
    def main(args: Array[String]) {
        val parser = new MyParser { override val buildParseTree = true }
        val fixed = "aaaaaaaaaaa"
        val result = TracingParseRunner(parser.all).run(fixed)
        println(result.result)
    }
}