policies. For this reason the <code class="computeroutput"><span class="identifier">multi_pass</span></code>
        library implements a template <code class="computeroutput"><span class="identifier">iterator_policies</span><span class="special">::</span><span class="identifier">default_policy</span></code>
        allowing to combine several different policies, each implementing one of
        the functionality groups:
      </p>
<div class="table">
<a name="spirit.support.multi_pass.policies_needed_for_d