title: angularjs Select with filter to filter out the option that's already selected
body: <p>My code for select with ng-model is working fine except filter stuff.
  Without filter, it's showing duplicated option for the already selected one..
  So I am trying to filter out the one already selected in below code.</p>
  
  <p>But it's not working.. Am I doing something wrong? any help please?</p>
  
  <pre><code>&lt;select ng-model="result.color"&gt;
  &lt;option ng-repeat="codes in obj.codes | filter:!result.color" value="{{codes.code}}"&gt;{{codes.code}}&lt;/option&gt;
  &lt;option ng-selected&gt;{{result.color}}&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>