title: Is it possible to include / exclude a list of files by refid in ant?
body: <p>We currently have an ant task that contains something similar to the following:</p>
  
  <pre><code>     &lt;filelist dir="${css.dir}" id="ordered_css"&gt;
          &lt;file name="interface/foo.css" /&gt;
          &lt;file name="pages/monkey.css" /&gt;
          &lt;file name="pages/ninja.css" /&gt;
          &lt;file name="pages/sidebar.css" /&gt;
          &lt;file name="pages/bar.css" /&gt;
          &lt;file name="pages/baz.css" /&gt;
          &lt;file name="pages/robot.css" /&gt;
       &lt;/filelist&gt;
  
       &lt;patternset id="exclude_css"&gt;
          &lt;exclude name="interface/foo.css" /&gt;
          &lt;exclude name="pages/monkey.css" /&gt;
          &lt;exclude name="pages/ninja.css" /&gt;
          &lt;exclude name="pages/sidebar.css" /&gt;
          &lt;exclude name="pages/bar.css" /&gt;
          &lt;exclude name="pages/baz.css" /&gt;
          &lt;exclude name="pages/robot.css" /&gt;
       &lt;/patternset&gt;
  </code></pre>
  
  <p>The task then references the patternset here:</p>
  
  <pre><code> &lt;fileset dir="${css.dir}" id="stuff_css" includes="*/stuff/*.css"&gt;
      &lt;patternset refid="exclude_css" /&gt;
   &lt;/fileset&gt;
  </code></pre>
  
  <p>And further down, it references the fileset here:</p>
  
  <pre><code>&lt;concat destfile="build/all.css" append="false" force="yes"&gt;
      &lt;filelist refid="ordered_css" /&gt;
      &lt;fileset refid="stuff_css" /&gt;
  &lt;/concat&gt;
  </code></pre>
  
  <p><strong>Is there a way to consolidate the two lists of files into one type that can be referenced in both places?</strong> So far I haven't been able to figure out a way, since the patternset contains excludes.  I was hoping for a way to simply create a list of files and include or exclude the referenced list.</p>