Scala compilation issue "forward reference extends over definition of value"

user_3002377 0
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Compilation error occurs for the below snippet only when it is method level implementation and error does not occur when it is defined in main. What is the difference ? Scala version used is 2.13.5.

class FibonacciGenerator  {
  def generate(total: Int): List[Int] = {
    val fibSeries: LazyList[Int] = LazyList.cons(1, LazyList.cons(1, fibSeries.zip(fibSeries.tail).map { t => t._1 + t._2 }))
    fibSeries.take(total).toList
  }
}

Same implementation does not fail below.

object Misc extends App {

  val x: LazyList[Int] = LazyList.cons(1, LazyList.cons(1, x.zip(x.tail).map{t => t._1 + t._2}))
  println(x)
  println(x.take(10).toList)
scala-2.13 lazy-evaluation scala
1 Answers

The difference is that in the latter case you are using objects which are created lazily

An object... is created lazily when it is referenced, like a lazy val.

In the first case it should work if you declare lazy val fibSeries.

user_52050220
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