title: validating a numeric input's length in laravel 5
body: <p><strong>foo.blade.php</strong></p>
  
  <pre><code>&lt;input type="text" name="national-id" /&gt;
  </code></pre>
  
  <p><strong>FooController.php</strong></p>
  
  <pre><code>$rules = [
      'national-id' =&gt; 'required|size:10|numeric'
  ];
  </code></pre>
  
  <p>the <code>national-id</code> field should contain <code>10</code> <code>digits</code> and I actually expected the code above to validate this , but instead It will check If the <code>national-id</code> exactly equals to 10 or not ...<br><br>
  how can I validate the <code>length</code> of a numeric field?</p>