public function addStaticInclude($file, $ext = '.js')
    {
        if (@$this->included['js-'.$file.$ext]++) {
            return $this;
        }

        if (strpos($file, 'http') !== 0 && $file[0] != '/') {
            $url = $this->app->locateURL('js', $file.$ext);
        } else {
            $url = $file;
        }

        $this->app->template->appendHTML(
            'js_include',
            '<script type="text/javascript" src="'.$url.'"></script>'."\n"
        );

        return $this;
    }