equals method

@override bool equals(Iterable<E>? elements1, Iterable<E>? elements2)

Compare two elements for being equal.

This should be a proper equality relation.

Implementation

@override
bool equals(Iterable<E>? elements1, Iterable<E>? elements2) {
  if (identical(elements1, elements2)) {
    return true;
  }
  if (elements1 == null || elements2 == null) {
    return false;
  }
  final Iterator<E> it1 = elements1.iterator;
  final Iterator<E> it2 = elements2.iterator;
  while (true) {
    final bool hasNext = it1.moveNext();
    if (hasNext != it2.moveNext()) {
      return false;
    }
    if (!hasNext) {
      return true;
    }
    if (!_elementEquality.equals(it1.current, it2.current)) {
      return false;
    }
  }
}