n><span class="special">(</span><span class="identifier">BidirectionalIterator</span> <span class="identifier">a</span><span class="special">,</span>
                     <span class="identifier">BidirectionalIterator</span> <span class="identifier">b</span><span class="special">,</span>
                     <span class="keyword">const</span> <span class="identifier">regex_type</span><span class="special">&amp;</span> <span class="identifier">re</span><span class="special">,</span>
                     <spa