clear method
void clear(Remove all elements from this linked list.
Source
void clear() {
  _modificationCount++;
  if (isEmpty) return;
  E next = _first;
  do {
    E entry = next;
    next = entry._next;
    entry._next = entry._previous = entry._list = null;
  } while (!identical(next, _first));
  _first = null;
  _length = 0;
}
    © 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
    https://api.dartlang.org/stable/1.24.3/dart-collection/LinkedList/clear.html