ction class="summary offset-anchor" id="operators">
      <h2>Operators</h2>
      <dl class="callables">
        <dt id="operator []" class="callable">
          <span class="name"><a href="dart-collection/MapMixin/operator_get.html">operator []</a></span><span class="signature">(<wbr><span class="parameter" id="[]-param-key"><span class="type-annotation"><a href="dart-core/Object-class.html">Object</a></span> <span class="parameter-name">key</span></span>)
            <span class="returntype parameter">&#