function handleCallback(value, resolver, callback) {
    var callbackOutput = null;
    try {
      if (isFunction(callback)) callbackOutput = callback();
    } catch (e) {
      return reject(e);
    }
    if (isPromiseLike(callbackOutput)) {
      return callbackOutput.then(function() {
        return resolver(value);
      }, reject);
    } else {
      return resolver(value);
    }
  }
@ngdoc filter
@name uppercase
@kind function
@description
Converts string to uppercase.
@example
   <example module="uppercaseFilterExample" name="filter-uppercase">
     <file name="index.html">
       <script>
         angular.module('uppercaseFilterExample', [])
           .controller('ExampleController', ['$scope', function($scope) {
             $scope.title = 'This is a title';
           }]);
       </script>
       <div ng-controller="ExampleController">
         <!-- This title should be formatted normally -->
         <h1>{{title}}</h1>
         <!-- This title should be capitalized -->
         <h1>{{title | uppercase}}</h1>
       </div>
     </file>
   </example>