e="boost_regex.syntax.basic_extended.variations"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.variations">Variations</a>
      </h4>
<h5>
<a name="boost_regex.syntax.basic_extended.h29"></a>
        <span class="phrase"><a name="boost_regex.syntax.basic_extended.egrep"></a></span><a class="link" href="basic_extended.html#boost_regex.syntax.basic_extended.egrep">Egrep</a>
      </h5>
<p>
        When an expression is compiled with the <a class="link" href="../ref/syn