title: php regexp exclude
body: <p>I use this to clean html from font tag :</p>
  
  <pre><code>$html = '&lt;font class="textmiddle" color="red"&gt;toto&lt;/font&gt;' ;
  $clean = preg_replace('/&lt;font[^&gt;]*&gt;/', '', $html) ;
  $clean = preg_replace('/&lt;\/font&gt;/', '', $clean) ;
  </code></pre>
  
  <p>It works like a charm.</p>
  
  <p>But, when the html string is :</p>
  
  <pre><code>$html = '&lt;font class="textmiddle" color="&lt;%= color.importanttext %&gt;"&gt;toto&lt;/font&gt;' ;
  </code></pre>
  
  <p>Then the result is not the expected one : </p>
  
  <pre><code>"&gt;toto
  </code></pre>