d>
  <table class="params">
    <tr><td class="paramname">instance</td><td>An opaque instance of the underlying type. </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>A wrapper containing the value of the underlying variable. </dd></dl>

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<h2 class="memtitle"><span class="permalink"><a href="#a148f106584bfdd2bb33591d790c4a1c1">&#9670;&#160;</a></span>is_const()</h2>

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