sh</span><span class="special">::</span><span class="identifier">block</span></code></a> or <a class="link" href="../boost__beast__zlib__Flush.html" title="zlib::Flush"><code class="computeroutput"><span class="identifier">Flush</span><span class="special">::</span><span class="identifier">trees</span></code></a> is used, and when <code class="computeroutput"><span class="identifier">write</span></code> avoids the allocation of memory
          for a sliding window when <a class="link" href="../boost__beast