ss="identifier">as_wstring</span></code>:
          </p>
<p>
            To properly handle string concatenation with <a class="link" href="../../../support/utree.html" title="The utree data structure"><code class="computeroutput"><span class="identifier">utree</span></code></a>, we make use of <code class="computeroutput"><span class="identifier">as_string</span><span class="special">[]</span></code>.
            We also use <code class="computeroutput"><span class="identifier">as</span><span class="specia