       is written into the dereferenced iterator, it is passed as a parameter
          to the function object.
        </li>
<li class="listitem">
          <a href="../generator_iterator.htm" target="_top"><code class="computeroutput"><span class="identifier">generator_iterator</span></code></a>:
          an input iterator wrapping a generator (nullary function object); each
          time the iterator is dereferenced, the function object is called to get
          the value to return. An outdated analog