identifier">pair</span><span class="special">&lt;</span> <span class="identifier">OutputIterator</span><span class="special">,</span> <span class="identifier">BidirectionalIterator</span> <span class="special">&gt;</span> 
  <span class="identifier">wait_some</span><span class="special">(</span><span class="identifier">BidirectionalIterator</span> first<span class="special">,</span> <span class="identifier">BidirectionalIterator</span> last<span class="special">,</span> 
            <span class="identifier"