
<p>If we want to find functions, variables, or anything else in an AST
we need to <span class="ix-entry" ix-key="walk a tree" markdown="1"><a class="gl-ref" href="../glossary/#walk_tree" markdown="1">walk the tree</a></span>,
i.e.,
to visit each node in turn.
The <a href="https://www.npmjs.com/package/acorn-walk"><code>acorn-walk</code></a> library will do this for us
using the <span class="ix-entry" ix-key="Visitor pattern;design pattern!Visitor" markdown="1">Visitor design pattern</span> we first saw in 