function ngTranscludeCloneAttachFn(clone, transcludedScope) {
          if (clone.length && notWhitespace(clone)) {
            $element.append(clone);
          } else {
            useFallbackContent();
            // There is nothing linked against the transcluded scope since no content was available,
            // so it should be safe to clean up the generated scope.
            transcludedScope.$destroy();
          }
        }
@ngdoc directive
@name ngTransclude
@restrict EAC

@description
Directive that marks the insertion point for the transcluded DOM of the nearest parent directive that uses transclusion.

You can specify that you want to insert a named transclusion slot, instead of the default slot, by providing the slot name
as the value of the `ng-transclude` or `ng-transclude-slot` attribute.

If the transcluded content is not empty (i.e. contains one or more DOM nodes, including whitespace text nodes), any existing
content of this element will be removed before the transcluded content is inserted.
If the transcluded content is empty (or only whitespace), the existing content is left intact. This lets you provide fallback
content in the case that no transcluded content is provided.

@element ANY

@param {string} ngTransclude|ngTranscludeSlot the name of the slot to insert at this point. If this is not provided, is empty
                                              or its value is the same as the name of the attribute then the default slot is used.

@example
### Basic transclusion
This example demonstrates basic transclusion of content into a component directive.
<example name="simpleTranscludeExample" module="transcludeExample">
  <file name="index.html">
    <script>
      angular.module('transcludeExample', [])
       .directive('pane', function(){
          return {
            restrict: 'E',
            transclude: true,
            scope: { title:'@' },
            template: '<div style="border: 1px solid black;">' +
                        '<div style="background-color: gray">{{title}}</div>' +
                        '<ng-transclude></ng-transclude>' +
                      '</div>'
          };
      })
      .controller('ExampleController', ['$scope', function($scope) {
        $scope.title = 'Lorem Ipsum';
        $scope.text = 'Neque porro quisquam est qui dolorem ipsum quia dolor...';
      }]);
    </script>
    <div ng-controller="ExampleController">
      <input ng-model="title" aria-label="title"> <br/>
      <textarea ng-model="text" aria-label="text"></textarea> <br/>
      <pane title="{{title}}"><span>{{text}}</span></pane>
    </div>
  </file>
  <file name="protractor.js" type="protractor">
     it('should have transcluded', function() {
       var titleElement = element(by.model('title'));
       titleElement.clear();
       titleElement.sendKeys('TITLE');
       var textElement = element(by.model('text'));
       textElement.clear();
       textElement.sendKeys('TEXT');
       expect(element(by.binding('title')).getText()).toEqual('TITLE');
       expect(element(by.binding('text')).getText()).toEqual('TEXT');
     });
  </file>
</example>

@example
### Transclude fallback content
This example shows how to use `NgTransclude` with fallback content, that
is displayed if no transcluded content is provided.

<example module="transcludeFallbackContentExample" name="ng-transclude">
<file name="index.html">
<script>
angular.module('transcludeFallbackContentExample', [])
.directive('myButton', function(){
            return {
              restrict: 'E',
              transclude: true,
              scope: true,
              template: '<button style="cursor: pointer;">' +
                          '<ng-transclude>' +
                            '<b style="color: red;">Button1</b>' +
                          '</ng-transclude>' +
                        '</button>'
            };
        });
</script>
<!-- fallback button content -->
<my-button id="fallback"></my-button>
<!-- modified button content -->
<my-button id="modified">
  <i style="color: green;">Button2</i>
</my-button>
</file>
<file name="protractor.js" type="protractor">
it('should have different transclude element content', function() {
         expect(element(by.id('fallback')).getText()).toBe('Button1');
         expect(element(by.id('modified')).getText()).toBe('Button2');
       });
</file>
</example>

@example
### Multi-slot transclusion
This example demonstrates using multi-slot transclusion in a component directive.
<example name="multiSlotTranscludeExample" module="multiSlotTranscludeExample">
  <file name="index.html">
   <style>
     .title, .footer {
       background-color: gray
     }
   </style>
   <div ng-controller="ExampleController">
     <input ng-model="title" aria-label="title"> <br/>
     <textarea ng-model="text" aria-label="text"></textarea> <br/>
     <pane>
       <pane-title><a ng-href="{{link}}">{{title}}</a></pane-title>
       <pane-body><p>{{text}}</p></pane-body>
     </pane>
   </div>
  </file>
  <file name="app.js">
   angular.module('multiSlotTranscludeExample', [])
    .directive('pane', function() {
       return {
         restrict: 'E',
         transclude: {
           'title': '?paneTitle',
           'body': 'paneBody',
           'footer': '?paneFooter'
         },
         template: '<div style="border: 1px solid black;">' +
                     '<div class="title" ng-transclude="title">Fallback Title</div>' +
                     '<div ng-transclude="body"></div>' +
                     '<div class="footer" ng-transclude="footer">Fallback Footer</div>' +
                   '</div>'
       };
   })
   .controller('ExampleController', ['$scope', function($scope) {
     $scope.title = 'Lorem Ipsum';
     $scope.link = 'https://google.com';
     $scope.text = 'Neque porro quisquam est qui dolorem ipsum quia dolor...';
   }]);
  </file>
  <file name="protractor.js" type="protractor">
     it('should have transcluded the title and the body', function() {
       var titleElement = element(by.model('title'));
       titleElement.clear();
       titleElement.sendKeys('TITLE');
       var textElement = element(by.model('text'));
       textElement.clear();
       textElement.sendKeys('TEXT');
       expect(element(by.css('.title')).getText()).toEqual('TITLE');
       expect(element(by.binding('text')).getText()).toEqual('TEXT');
       expect(element(by.css('.footer')).getText()).toEqual('Fallback Footer');
     });
  </file>
</example>