r to earlier versions as
        <a href="../../../../../../libs/spirit/classic/index.html" target="_top"><span class="emphasis"><em>Spirit.Classic</em></span></a>).
        The parser generators are now only one part of the whole library. The parser
        submodule of <a href="http://boost-spirit.com" target="_top">Spirit</a> is now called
        <span class="emphasis"><em>Spirit.Qi</em></span>. It is conceptually different and exposes
        a completely different interface. Generally, there is no eas