entifier">filter_iterator</span></code>
        and then <code class="computeroutput"><span class="identifier">make_filter_iterator</span></code>
        to output only the positive integers from an array of integers. Then <code class="computeroutput"><span class="identifier">make_filter_iterator</span></code> is is used to output
        the integers greater than <code class="computeroutput"><span class="special">-</span><span class="number">2</span></code>.
      </p>
<pre class="programlisting"><span cla