title: Validate an array of integers
body: <p>Given an array of integers:</p>
  
  <pre><code>[1, 2, 3, 4, ...]
  </code></pre>
  
  <p>How can I use the validator to check if each of these exists in a table? Possible without a <code>foreach</code> loop?</p>
  
  <pre><code>$validator = Validator::make($request-&gt;all(), [
      'array' =&gt; 'required|exists:users,id'
  ]);
  </code></pre>