title: Property binding not working in ngFor loop
body: <p>When I'm binding my hidden property to a variable it is working but not working when interpolation of binding in a loop of <code>ngFor</code> value.</p>
  
  <p>I've tried like this [hidden]="!(column.key)" and also hidden="!{{column.key}}" and hidden="{{!column.key}}" it is not working that way but working when binding direct to a variable like [hidden]="!name"
  and name is my one of a Boolean variable.</p>
  
  <pre><code>&lt;table mat-table [dataSource]="dataSource"&gt;
      &lt;ng-container matColumnDef="{{column.key}}" *ngFor="let column of displayedColumns"&gt;
          &lt;th mat-header-cell *matHeaderCellDef [hidden]="!(column.key)"&gt; {{column.key}} &lt;/th&gt;
          &lt;td mat-cell *matCellDef="let element" [hidden]="!(column.key)"&gt; {{element[column.value]}} &lt;/td&gt;
      &lt;/ng-container&gt;
      &lt;/ng-container&gt;
      &lt;tr mat-header-row *matHeaderRowDef="columnsToDisplay"&gt;&lt;/tr&gt;
      &lt;tr mat-row *matRowDef="let row; columns: columnsToDisplay;"&gt;&lt;/tr&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>The hidden property should work like this because the <code>column.key</code> has same value as the name of variables.</p>