f lines read so far.</li>
<li><code class="code">n</code>: returns the number of characters read so far.</li>
<li><code class="code"><span class="constructor">N</span></code> or <code class="code"><span class="constructor">L</span></code>: returns the number of tokens read so far.</li>
<li><code class="code">!</code>: matches the end of input condition.</li>
<li><code class="code">%</code>: matches one <code class="code">%</code> character in the input.</li>
<li><code class="code">@</code>: matches one <cod