title: JS create array with arrow function and rest parameters
body: <p>In one app I saw this part of code:</p>
  <pre><code>const arrayCreate = length =&gt; [...Array(length)];
  </code></pre>
  <p>It works, but I'm not sure how. We have a arrow function that takes a length parameter, and creates an array in array or what? :)
  And what does the spread operator doing here?</p>