<li class="section-title"><a href="dart-core/Duration-class.html#operators">Operators</a></li>
      <li><a href="dart-core/Duration/operator_multiply.html">operator *</a></li>
      <li><a href="dart-core/Duration/operator_plus.html">operator +</a></li>
      <li><a href="dart-core/Duration/operator_minus.html">operator -</a></li>
      <li><a href="dart-core/Duration/operator_less.html">operator <</a></li>
      <li><a href="dart-core/Duration/operator_less_equal.html">operator <=</a></li>
      <li><a hr