d <code>below</code> are trivial to write. <code>rotate</code> is similarly simple.</li>
<li>The real punchline comes when you look at the means of abstraction. Since painters are just procedures, everything that Lisp supplies for procedures is automatically available to us in this painting language.</li>
<li>We can write recursive painters without ever having purposely built recursion into the painting language. We can even write higher-order painters.</li>
</ul>
<h3 id="3.2" class="anchor">
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