mputeroutput"><span class="identifier">first</span></code>
              is reset to its position before entering the parser function. <span class="emphasis"><em>attr</em></span>
              is untouched.
            </li>
</ul></div>
<div class="variablelist">
<p class="title"><b>void what(context)</b></p>
<dl>
<dt><span class="term"><code class="computeroutput"><span class="identifier">context</span></code></span></dt>
<dd><p>
                enclosing rule context (can be <code class="computeroutput"><