</span><span class="special">()</span><span class="keyword">const</span><span class="special">;</span>
</pre>
<p>
        <span class="bold"><strong>Requires</strong></span>: that the match_results object
        has been initialized as a result of a successful call to <a class="link" href="regex_search.html" title="regex_search"><code class="computeroutput"><span class="identifier">regex_search</span></code></a> or <a class="link" href="regex_match.html" title="regex_match"><code class="computeroutput"><sp