add comment to function

libraries/transformations/global.inc.php

@@ -23,7 +23,20 @@
  */
 
 /**
+ * Replaces "[__BUFFER__]" occurences found in $options['string'] with the text
+ * in $buffer, after performing a regular expression search and replace on 
+ * $buffer using $options['regex'] and $options['regex_replace'].
  *
+ * @param string $buffer        text that will be replaced in $options['string'],
+ *                              after being formatted
+ * @param array  $options       the options required to format $buffer
+ *               = array (
+ *                 'string'          => 'string',    // text containing "[__BUFFER__]"
+ *                 'regex'           => 'mixed',     // the pattern to search for
+ *                 'regex_replace'   => 'mixed',     // string or array of strings to replace with
+ *               );
+ *
+ * @return string containing the text with all the replacements
  */
 function PMA_transformation_global_html_replace($buffer, $options = array())
 {