  to be passed into the <code class="computeroutput"><span class="identifier">generate</span></code>
            functions. The functions taking two or more attributes are usable when
            the generator expression is a <a class="link" href="../operator/sequence.html" title="Sequence Generator (a &lt;&lt; b)">Sequence
            (<code class="computeroutput"><span class="special">&lt;&lt;</span></code>)</a> only.
            In this case each of the attributes passed have to match the corresponding
 