angularjs - Badident error when using "as" in ng-repeat -

i have following code filters through table of results:

<strong>clients [ {{ results.length }} ]</strong>  <thead ng-show="clientsearch">         <tr>             <th><i class="fa fa-search"></i></th>             <th class="search-box">                 <input type="text" placeholder="search name" ng-model="searchresult.firstname">             </th>             <th class="search-box">                 <input type="text" placeholder="search surname" ng-model="searchresult.lastname">             </th>             <th class="search-box">                 <input type="text" placeholder="search address" ng-model="searchresult.address">             </th>             <th class="search-box">                 <input type="text" placeholder="search email" ng-model="searchresult.email">             </th>             <th class="search-box">                 <input type="number" placeholder="search mobile" ng-model="searchresult.mobile">             </th>              <th class="search-box">                 <input type="date" class="datepicker" placeholder="search date" ng-model="searchresult.registrationdate">             </th>         </tr>         </thead> 

this code produces table data:

<tr ng-repeat="client in clients results  | filter : searchresult " ng-dblclick="open(client)">             <td>{{$index + 1}}</td>             <td>{{client.firstname}}</td>             <td>{{client.lastname}}</td>             <td>{{client.address}}</td>             <td>{{client.email}}</td>             <td>{{client.mobile}}</td>             <td>{{client.registrationdate | date: 'medium'}}</td>             <td ng-if="results.length === 0">no results found</td>         </tr> 

but error https://code.angularjs.org/1.3.16/docs/error/ngrepeat/badident when try use ngrepeat.

any suggestions on how can fix this.