   sequence as the key to be used for lookup. The type of that first element
            needs to be convertible to <code class="computeroutput"><span class="identifier">Attrib</span></code>.
            In this case the second element of the <a href="../../../../../../../../libs/fusion/doc/html/index.html" target="_top">Boost.Fusion</a>
            sequence is used as the attribute while calling a generator derived from
            the value stored in the symbol table for the found entry.
          </p>
<p