public function filterStylesheetUri($css, WPLessStylesheet $stylesheet) { $this->_TmpBaseDir = dirname($stylesheet->getSourceUri()); return preg_replace_callback('#url\\s*\\((?P<quote>[\'"]{0,1})(?P<url>[^\'"\\)]+)\\1\\)#siU', array($this, '_filterStylesheetUri'), $css); unset($this->_TmpBaseDir); }