angular/angular.js

<div ng-app="selectBenchmark" ng-cloak>
  <div ng-controller="DataController">
    <div class="container-fluid">
      <p>
        Tests the execution of a select with ngRepeat'ed options with ngValue for rendering during model
        and option updates.
      </p>
      <select ng-model="x">
        <optgroup ng-repeat="g in groups track by g.name" label="{{g.name}}">
          <option ng-repeat="a in g.items track by a.id" ng-value="a">{{a.label}}</option>
        </optgroup>
      </select>
    </div>
  </div>
</div>