title: How to tell an Applescript to stop executing
body: <p>Applescript's "choose from list" user interaction has a "cancel" button — I want this "cancel" to tell the script to immediately stop executing. In other words:</p>
  
  <pre><code> set wmColor to choose from list {"Black", "Black for all", "White", 
       "White for all"} with prompt "What color should the watermark be?" 
       default items "White for all" without multiple selections allowed and 
       empty selection allowed
   if wmColor is false
       *tell script to stop executing*
   end if
  </code></pre>
  
  <p>Can't seem to find how to do this — does anyone know how?</p>