title: Create String list in Groovy
body: <p>The following code in Groovy adds <code>GString</code>s to the list:</p>
  
  <pre><code>List&lt;String&gt; args = [ 'cmd', "-Dopt=${value}" ]
  </code></pre>
  
  <p>When I create a <code>ProcessBuilder</code> with this list, I get a <code>ClassCastException</code>. What's a groovy way to coerce the list elements to the correct type?</p>