an><span class="special">&lt;</span><span class="keyword">typename</span> InputIterator<span class="special">,</span> <span class="keyword">typename</span> V<span class="special">&gt;</span> 
  <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="keyword">bool</span> 
  <span class="identifier">one_of_equal</span><span class="special">(</span><span class="identifier">InputIterator</span> first<span class="special">,</span> <span class="identifier">InputIterator</span> last<span class="special"