he syntax for getting an element out of a data structure.
Another difference is that while `put` returns the data structure, `set` evaluates
to the new value.
</p>
<h2>Using an Array as a Stack
</h2>
<p>Arrays can also be used for implementing efficient stacks. The
Janet core library provides three functions that can be used
to treat an array as a stack.
</p>
<ul><li><code class="mendoza-code">(array/push stack value)</code></li>
    <li><code class="mendoza-code">(array/pop stack)</code></li>
    <li><code