gistfile1.scala

import java.io.PrintWriter

import scala.io.Source
import scala.util.continuations._

trait ContextType[B]

def contextType[B]: ContextType[B] = null

def using[A <: AutoCloseable, B: ContextType](resource: A)(op: A => B) = {
  try op(resource)
  finally resource.close()
}

def resource[A <: AutoCloseable, B: ContextType](r: A) = shift(using[A, B](r))

def withResources[B](op: => B@cps[B]) = reset(op)

withResources {
  implicit val _ = contextType[Unit]
  val w1 = resource(new PrintWriter("col1.txt"))
  val w2 = resource(new PrintWriter("col2.txt"))

  Source.stdin.getLines().map(_.split("\t")).foreach {
    case Array(col1, col2, _*) =>
      w1.println(col1)
      w2.println(col2)
    case Array(col1) => w1.println(col1)
  }
}