nged from the last section.
          We still utilize a very similar scheme. We have an alternative providing
          the formatting rules for our both use cases: one for the full complex format
          and one for complex numbers with a zero imaginary part. But instead of
          selecting the required alternative by comparing the imaginary part to zero
          in the grammar we assume to receive a boolean attribute carrying this information:
        </p>
<pre class="programlisting"><span class="s