title: Replace content between two tags with preg_replace (php)
body: <p>I have a string like this:</p>
  
  <p><code>(link)there is link1(/link), (link)there is link2(/link)</code></p>
  
  <p>Now i want to set the links that it look like this:</p>
  
  <p><code>&lt;a href='there is link1'&gt;there is link1&lt;/a&gt;, &lt;a href='there is link2'&gt;there is link2&lt;/a&gt;</code></p>
  
  <p>I tried with preg_replace but the result is an error (<code>Unknown modifier 'l'</code>)</p>
  
  <p><code>preg_replace("/\(link\).*?\(/link\)/U", "&lt;a href='$1'&gt;$1&lt;/a&gt;", $return);</code></p>