pan class="special">&amp;</span> <span class="identifier">e</span><span class="special">,</span>
         <span class="keyword">int</span> <span class="identifier">sub</span><span class="special">,</span>
         <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">match_flag_type</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">matc