title: How can I pass multiple params into a directive?
body: <p>I have a directive:</p>
  
  <pre><code>app.directive('testDir', [function () {
      return {
          require: '?ngModel',
          link: function ($scope, elm, attr, ngModel) {
              var abc=attr.testDir;
              var def=&lt; The value zzz &gt;
          }
      };
  }])
  </code></pre>
  
  <p>I understand I can call this like:</p>
  
  <pre><code>&lt;div test-dir='abcd'&gt;xx&lt;/div&gt;
  </code></pre>
  
  <p>What if I also needed to pass the parameter 'zzz'.  How can I pass more than one parameter to my directive?</p>