 derived from a corresponding
        instantiation of <code class="computeroutput"><span class="identifier">iterator_facade</span></code>
        and implement the core behaviors in terms of the <code class="computeroutput"><span class="identifier">Base</span></code>
        type. In essence, <code class="computeroutput"><span class="identifier">iterator_adaptor</span></code>
        merely forwards all operations to an instance of the <code class="computeroutput"><span class="identifier">Base</span></code