title: Masking a string
body: <p>I need to put a received string in this format:</p>
  <p><code>&quot;## ## ## ###&quot;</code> in typescript/javascript</p>
  <p><strong>Eg</strong>:</p>
  <p><code> &quot;12 34 56 789&quot;</code></p>
  <p>I know there's <code>string-mask</code> and some way via JQuery, is there a simplier way to do it?</p>