function main_autoload( $class_name )
{
    global $xpl_file_tree ;
    global $tags_tree ;
    //Loading Xpl Library
    $xpl_filename = strtolower ( $class_name ) . '.php' ;
    $xpl_class_node = $xpl_file_tree -> find_node_by_property_from_root ( 'name' , $xpl_filename ) ;
    $xpl_file = $xpl_class_node -> properties[ 'path' ] ;

    if ( is_file ( SITE_PATH . $xpl_file ) )
    {
        include SITE_PATH . $xpl_file ;
        return ;
    }
}