title: minimum length of characters in regex
body: <p>I have the following regex: <code>^([0-9]{1,4}(\ -?)){3}[0-9]{1,4}$</code></p>
  
  <p>As it is, it matches <code>1234</code></p>
  
  <p>I would like to force to match only on 6 or more digits (ie. not including dashes) eg. 1234 12 or 12 1 123 or 1 1 123 1 or 1-12-12-2222 or 1-123 2 2 etc.</p>
  
  <p>Is there a simple way to achieve this?</p>