Adds all elements of iterable at the end of the queue. The length of the queue is extended by the length of iterable.
void addAll(Iterable<E> iterable) {
  for (final E value in iterable) {
    _sentinel._prepend(value);
    _elementCount++;
  }
}
    © 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
    https://api.dart.dev/stable/2.5.0/dart-collection/DoubleLinkedQueue/addAll.html