title: exclude underscore from alpha numeric regex
body: <p>I want use <code>\w</code> regex for to allow alpha numeric but I don't want underscore <code>_</code> to be part of it. Since <code>_</code> is included in <code>\w</code>. So I have coded like this but doesn't work, what is my mistake?</p>
  
  <pre><code>(/^roger\w{2,3}[0-9a-z]/i)
  </code></pre>
  
  <p>I am expecting any character other than A-Z or 1-2 to be exclude </p>
  
  <p>ex -
  <code>roger3_2 or roger46_ or roger2_</code></p>
  
  <p>but</p>
  
  <blockquote>
    <p>roger54 or roger4a or roger455 or rogerAAA</p>
  </blockquote>
  
  <p>are to be ok</p>