</a>&gt;::value</code>.
                </p></li>
<li class="listitem"><p>
                  If <code class="computeroutput">T</code> is derived from <code class="computeroutput"><a class="link" href="callable.html" title="Struct callable">proto::callable</a></code>,
                  <code class="computeroutput">proto::is_callable&lt;T&gt;::value</code> is <code class="computeroutput">true</code>.
                </p></li>
<li class="listitem"><p>
                  Otherwise, <code class="computeroutput">p