op</span></code>
        and <code class="computeroutput"><span class="identifier">local</span><span class="special">::</span><span class="identifier">can_call_func</span></code> traits:
      </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">local</span>
<span class="special">{</span>
    <span class="identifier">BOOST_DECLARE_IS_CALLABLE</span><span class="special">(</span><span cl