Scala.js - download browser-generated file

download_file.scala

import org.scalajs.dom.document
import org.scalajs.dom.window
import org.scalajs.dom.URL
import org.scalajs.dom.Blob

def download(filename: String, contents: Blob): Unit = {
  val elem = window.document.createElement("a").asInstanceOf[HTMLAnchorElement];
  elem.href = URL.createObjectURL(contents);
  elem.download = filename;        
  document.body.appendChild(elem);
  elem.click();        
  document.body.removeChild(elem);
}