title: ngFor with nested selects
body: <p>How can I use <code>ngFor</code> correctly using a nested select?
  My current code is this:</p>
  
  <pre class="lang-js prettyprint-override"><code>&lt;tr *ngFor="let role of user.roles"&gt;
    &lt;td&gt;{{role.permissionId}}
       &lt;select class="form-control" [(ngModel)]="role.permissionId" name="permissions"&gt;                       
          &lt;option *ngFor="let permission of permissions" [ngValue]="permission.key"&gt;{{permission.value}}
          &lt;/option&gt;                        
       &lt;/select&gt;    
    &lt;/td&gt;                                     
  &lt;/tr&gt;
  </code></pre>
  
  
  
  <p>The select is filled corectly with all options but the value selected dont correspond to the object(role). When I push a new element to the array all the dropdowns take the same value.</p>