title: Angular destroy directive manually
body: <p>There is a way to remove directive manually? For example, I want to do some work only once and remove the directive, so it won't stay in memory. </p>
  
  <pre><code>@Directive({
    selector: '[doSomething]'
  })
  export class DoSomethingDirective {
  
    constructor(private el: ElementRef) {
      // do something with the element and destroy the directive
    }
  
  }
  </code></pre>