Coincidentally just saw this video a few days ago.<p>Interesting approach, to use RPN for expressions, including for the condition in the while statement.<p>I could understand most of the logic of the interpreter, except for the part about how the while statement is implemented.<p>I did not quite understand the parts of the code with<p><pre><code> case "while"
</code></pre>
and<p><pre><code> case "end
</code></pre>
fragments.<p>That is, around the region of lines 11 to 14 or so, at about 18:0 in the video.<p>How does the code there, work?