EvalQuestion2.scala

object Main extends App {

  import cats._
  import cats.implicits._

  val ans: Eval[Int] = for {
    a <- Eval.now { println("a"); 40 }
    b <- Eval.always { println( "b" ); 2 }
    c <- Eval.later { println( "c" ); 2 }
  } yield {
    println("Adding!")
    a + b + c
  }

  println("---")
  ans.value // ignored
  ans.value // ignored

}