Comparing Scala's List#map to Haskell's map

gistfile1.hs

-- http://hackage.haskell.org/package/base-4.6.0.1/docs/src/GHC-Base.html#map

map :: (a -> b) -> [a] -> [b]
map _ []     = []
map f (x:xs) = f x : map f xs

gistfile2.scala

// https://github.com/scala/scala/blob/c5962b1871f8093fe200fe0c47cd9c202b07a8f9/src/library/scala/collection/immutable/List.scala#L270-L287

@noinline // TODO - fix optimizer bug that requires noinline (see SI-8334)
final override def map[B, That](f: A => B)(implicit bf: CanBuildFrom[List[A], B, That]): That = {
  if (bf eq List.ReusableCBF) {
    if (this eq Nil) Nil.asInstanceOf[That] else {
      val h = new ::[B](f(head), Nil)
      var t: ::[B] = h
      var rest = tail
      while (rest ne Nil) {
        val nx = new ::(f(rest.head), Nil)
        t.tl = nx
        t = nx
        rest = rest.tail
      }
      h.asInstanceOf[That]
    }
  }
  else super.map(f)
}