</span><span class="special">::</span><span class="identifier">classic</span></code>.
        All references to the former namespace <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span></code>
        need to be adjusted as soon as the header names are corrected as described
        above. As an alternative you can define the preprocessor constant <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_USE_OLD_NAME