 visitor return a function object, thus
        delaying application of the visitor to any operands.</td>
</tr>
<tr>
<td><p><span class="term">Requires:</span></p></td>
<td>The given visitor must fulfill the
        <a class="link" href="../variant/reference.html#variant.concepts.static-visitor" title="StaticVisitor"><span class="emphasis"><em>StaticVisitor</em></span></a>
        concept requirements with respect to each of the bounded types of the
        given <code class="computeroutput">variant</code>.