Is there a way to pass a parameter to an arcade expression?

JeffreySchmidt3000

Is there a way to pass a parameter to an arcade expression in JSAPI 3.20 or get the value of a select, text box... or anything in the DOM?  I have tried using vanilla javascript and jquery to handle this, but it always throws an error when I try to reference the DOM from within the arcade <script> tag.  The following sample https://developers.arcgis.com/javascript/3/jssamples/renderer_arcade.html doesnt really show what I need and I could not find it in the Arcade documentation.  I need to look at a string of tags and check whether a select value is contained in this string.  This logic updates a UniqueValueRenderer...

Thanks!