>!</span><span class="identifier">re</span><span class="special">.</span><span class="identifier">empty</span><span class="special">()</span></code>. Object <span class="emphasis"><em>re</em></span> shall exist
        for the lifetime of the iterator constructed from it.
      </p>
<p>
        <span class="bold"><strong>Effects</strong></span>: constructs a <a class="link" href="regex_token_iterator.html" title="regex_token_iterator"><code class="computeroutput"><span class="identifier">regex_token_iterato