Postfilters
  Template postfilters are PHP functions that your templates are ran through
  after they are compiled. Postfilters can be either
  registered or loaded
  from the plugins directory
  by using
  load_filter() function or by
  setting
  $autoload_filters
  variable. Smarty will pass the compiled template code as the first
  argument, and expect the function to return the result of the
  processing.
 
Example 15-3. using a template postfilter 
<?php // put this in your application function add_header_comment($tpl_source, &$smarty) {     return "<?php echo \"<!-- Created by Smarty! -->\n\"; ?>\n".$tpl_source; }
  // register the postfilter $smarty->register_postfilter('add_header_comment'); $smarty->display('index.tpl'); ?>
 |  
 
   This will make the compiled Smarty template index.tpl look like:
   <!-- Created by Smarty! -->
{* rest of template content... *} |  
  | 
 See also register_postfilter(),
 prefilters
 and
 load_filter()