d to take <code>state</code> as a parameter
because it&rsquo;s contained in the object that they&rsquo;re part of.
That simplifies the methods&mdash;one less parameter&mdash;but it does mean that
anyone who wants to use our visitor has to derive a class,
which is a bit more complicated than writing a function.
This tradeoff is a sign that managing state is part of the problem&rsquo;s
<span class="ix-entry" ix-key="intrinsic complexity" markdown="1"><a class="gl-ref" href="../glossary/#intrinsic_complexity" 