arse-tree.svg" alt="A small parse tree"/>
  <figcaption markdown="1">Figure 14.1: The parse tree of a simple program.</figcaption>
</figure>

<p>Acorn&rsquo;s output is in <span class="ix-entry" ix-key="Esprima format" markdown="1"><a href="https://esprima.org/">Esprima</a> format</span>
(so-called because it was originally defined by a tool with that name).
The format&rsquo;s specification is very detailed,
but we can usually figure out most of what we need by inspection.
For example,
here is the output fo