lass="computeroutput"><span class="special">*</span></code> operator will match the
        preceding atom <span class="emphasis"><em>zero or more times</em></span>, for example the expression
        <code class="computeroutput"><span class="identifier">a</span><span class="special">*</span><span class="identifier">b</span></code> will match any of the following:
      </p>
<pre class="programlisting">b
ab
aaaaaaaab
</pre>
<p>
        The <code class="computeroutput"><span class="special">+</span></code> o