title: Google Apps Script: how to create autocomplete with optional param using JSDOC?
body: <p>Using jsdoc, I'd like to have optional parameter (like when you start typing <code>=split(</code> and it shows the last 2 params are optional. Google's <a href="https://developers.google.com/apps-script/guides/sheets/functions#autocomplete" rel="nofollow noreferrer">custom function page</a> shows an example of jsdoc applied to a custom function but doesn't show optional params. It does point you to <a href="https://jsdoc.app/tags-param.html" rel="nofollow noreferrer">jsdoc</a>, and if you browse there you will find that it lists two ways of showing optional parameters:</p>
  
  <pre><code>* @param {string} [somebody] - Somebody's name.
  * @param {string=} somebody - Somebody's name.
  </code></pre>
  
  <p>with the second one being even a <code>Google Closure Compiler syntax</code>. But None of these worked.</p>
  
  <p>I've check <a href="https://stackoverflow.com/questions/54383589/jsdoc-for-showing-optional-arguments-in-google-sheets-autocomplete-dropdown">this</a> and <a href="https://stackoverflow.com/questions/5873927/how-to-indicate-param-is-optional-using-inline-jsdoc">this</a>, and the first link is basically my question, but the answer just says "Google doesn't support it", which I find to be a very non-compelling answer as I have not seem anywhere Google stating they don't support it. So, my question is, did anyone make it work or has answers to it?</p>