es the elements in sorted order.</li></ul>
<p>It is generally not allowed to modify the set (add or remove elements) while
an operation on the set is being performed, for example during a call to
<a href="dart-core/Iterable/forEach.html">forEach</a> or <a href="dart-core/Set/containsAll.html">containsAll</a>. Nor is it allowed to modify the set while
iterating either the set itself or any <a href="dart-core/Iterable-class.html">Iterable</a> that is backed by the set,
such as the ones returned by methods lik