title: Set minimum and maximum characters in a regular expression
body: <p>I've written a <a href="http://en.wikipedia.org/wiki/Regular_expression" rel="noreferrer">regular expression</a> that matches any number of letters with any number of single spaces between the letters. I would like that regular expression to also enforce a minimum and maximum number of characters, but I'm not sure how to do that (or if it's possible).</p>
  
  <p>My regular expression is:</p>
  
  <pre><code>[A-Za-z](\s?[A-Za-z])+
  </code></pre>
  
  <p>I realized it was only matching two sets of letters surrounding a single space, so I modified it slightly to fix that. The original question is still the same though.</p>
  
  <p>Is there a way to enforce a minimum of three characters and a maximum of 30?</p>