title: Using TS Enum Flags in Angular 2+ template
body: <p>In Angular is it possible to use TypeScript's Enum Flags inside the template?<br>
  I'm getting a rejection with the "&amp;" bitwise operator.<br>
  I suspect it's not possible, just double checking.  </p>
  
  <pre><code>export enum Flags {
    Virgin  = 0,
    Loading = 1 &lt;&lt; 0,
    Loaded  = 1 &lt;&lt; 1,
    Hidden  = 1 &lt;&lt; 2,
  }
  // component.ts
    public flags = Flags;
  // component.html
    *ngIf="(userDetailsFlags$ | async) &amp; flags.Loaded"
  // Error:
  Parser Error: Unexpected token &amp;, expected identifier, keyword, or string at
  </code></pre>
  
  <p><strong>Update:</strong>
  To everyone commenting about using "&amp;&amp;" instead of "&amp;", please read <a href="https://basarat.gitbooks.io/typescript/docs/enums.html#enums-as-flags" rel="nofollow noreferrer">this document first</a>.<br>
  I know full well the difference between the two.</p>