
</li>
<li>
<p>a <strong>primitive value</strong> (sometimes also called a constant) <code>42</code></p>
</li>
</ul>
<p>Let’s take a slightly more complex example: the <em>church</em> encoding of pairs in the lambda-calculus (here the one embedded in Clojure).</p>
<pre><code class="language-clojure">(def pair (fn [x] (fn [y] (fn [z] ((z x) y)))))
(def fst (fn [p] (p (fn [x] (fn [y] x)))))
(def snd (fn [p] (p (fn [x] (fn [y] y)))))
</code></pre>
<p>Here are a few example:</p>
<pre><code class="language-clo