I'm working on a simple Template class (Mucklate) and I'm having a visibility problem with one of the methods. How can I allow the anonymous callback function for ob_start to access the parseTemplate method if I make the parseTemplate private static? I would rather it be invisible outside the class. Any other way I can achieve this?

(This isn't the whole class, and it's still in progress, so if it looks odd, that's why.)
PHP Code:
        public function __construct($templatePath$stripWhitespace false){

            if(
$templatePath && file_exists($templatePath)){
                
                
ob_start(function($buffer){ return Mucklate::parseTemplate($buffer); });
                
                include(
$templatePath);
                            
            }
            
        }
                
        public static function 
parseTemplate($buffer){
            
            foreach(
Mucklate::$varSet as $var){
                                
                
$buffer str_replace(Mucklate::$delimiter $var["var"] . strrev(Mucklate::$delimiter), $var["value"], $buffer);
                
            }
            
            return 
$buffer;
            
        }