">::</span><span class="identifier">_2</span></code>,
            etc. (yes, these placeholders are defined in the global namespace).
          </p>
<p>
            For <a href="../../../../../../../libs/lambda/index.html" target="_top">Boost.Lambda</a> use
            the placeholders defined in the namespace <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">lambda</span></code>.
          </p>
<p>
            For semantic actions writ