_matched"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.what_gets_matched">What
        Gets Matched</a>
      </h5>
<p>
        When there is more that one way to match a regular expression, the "best"
        possible match is obtained using the <a class="link" href="leftmost_longest_rule.html" title="The Leftmost Longest Rule">leftmost-longest
        rule</a>.
      </p>
<h4>
<a name="boost_regex.syntax.basic_extended.h28"></a>
        <span class="phrase"><a nam