       <h5 class="title"><a id="idp50491480"></a>x</h5>
                </div>
              </div>
            </div>
            <p>The target key to find. </p>
          </div>
          <div class="sect4" lang="en" xml:lang="en">
            <div class="titlepage">
              <div>
                <div>
                  <h5 class="title"><a id="idp50495536"></a>readonly</h5>
                </div>
              </div>
            </div>
            <p>Whether the returned iterator is readonly. </p>
