title: regular expression in perl in form get
body: <pre><code>my $formget='(90-?A(SB)?)';
  
  if ($form_type=~/$formget/i)
  </code></pre>
  
  <p>This regular expression gets files that are 90-A and 90-ASB but it also gets 90-A/A and 90-ASB/A.</p>
  
  <p>But I want to get ONLY those that have 90-A and 90-ASB and NOT those with 90-A/A and 90-ASB/A..</p>
  
  <p>What change should I make ?</p>