irror the syntax for getting an element out of a data structure.  Another
difference is that while <code class="mendoza-code">put</code> returns the data structure, <code class="mendoza-code">set</code> evaluates to
the new value.
</p>
<h2 id="Using-an-array-as-a-stack">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 