protected function _id($id)
    {
        if (($id !== null) && isset($this->_options['cache_id_prefix'])) {
            return $this->_options['cache_id_prefix'] . $id; // return with prefix
        }
        return $id; // no prefix, just return the $id passed
    }
protected function _id($id)
    {
        if (($id !== null) && isset($this->_options['cache_id_prefix'])) {
            return $this->_options['cache_id_prefix'] . $id; // return with prefix
        }
        return $id; // no prefix, just return the $id passed
    }
protected function _id ( $ id ) { if ( ( $ id !== null ) && isset ( $ this -> _options [ 'cache_id_prefix' ] ) ) { return $ this -> _options [ 'cache_id_prefix' ] . $ id ; // return with prefix } return $ id ; // no prefix, just return the $id passed }
Make and return a cache id

Checks 'cache_id_prefix' and returns new id with prefix or simply the id if null

@param  string $id Cache id
@return string Cache id (with or without prefix)
Make and return a cache id