printing an infinite Stream with Scalaz effects

infinite.scala

import scalaz._
import Scalaz._
import effects._

object Main extends App {

  /* Haskell-style pure main */
  def pmain: IO[Unit] = {
    val infiniteStream: Stream[String] = Stream continually "hello, world"
    infiniteStream.foldr(().pure[IO]) { (el, acc) =>
      for {
        _ <- putStrLn(el)
        _ <- acc
      } yield ()
    }
  }

  pmain.unsafePerformIO
}