e a default value if not supplied by the caller. Janet has support for this via
the <code class="mendoza-code">&amp;opt</code> symbol in parameter lists, where all parameters after <code class="mendoza-code">&amp;opt</code> are
<code class="mendoza-code">nil</code> if not supplied.
</p>
<pre class="mendoza-codeblock"><code data-language="janet">(<span class="mdzsyn-coresym">defn</span> <span class="mdzsyn-symbol">my-opt-function</span>
 <span class="mdzsyn-string">"A dumb function with optional arguments."<