1.
      <?php
   2.
       
   3.
        function returnStringRST($text, $openingMarker, $closingMarker) {
   4.
         $openingMarkerLength = strlen($openingMarker);
   5.
         $closingMarkerLength = strlen($closingMarker);
   6.
       
   7.
         $result = "";
   8.
         $position = 0;
   9.
       
  10.
         if(($position = strpos($text, $openingMarker, $position)) !== false) {
  11.
       
  12.
           if (($closingMarkerPosition = strpos($text, $closingMarker, $position)) !== false) {
  13.
             $replaceThis = substr($text, $position-$openingMarkerLength, $closingMarkerPosition - $closingMarkerLength);
  14.
             $text = ereg_replace($replaceThis, '', $text);
  15.
             returnStringRST($text,  "<!--", "-->");
  16.
       
  17.
           }
  18.
         }
  19.
         return $text;
  20.
        }
  21.
       
  22.
       
  23.
        $testText = "Before comment <!-- comment--> before comment2 <!-- comment2 --> after comment2";
  24.
        $result = returnStringRST($testText, "<!--", "-->");
  25.
        print($result);
  26.
       
  27.
      ?>