// turn string array of angle-bracketed elements into numeric array
// e.g. "<1><2><3>" => array(1,2,3);
preg_match_all('/<(' . Group::FOLLOWERS . '|'. Group::MUTUALS . '|[0-9]+)>/', $ids, $matches, PREG_PATTERN_ORDER);
// turn string array of angle-bracketed elements into numeric array
// e.g. "<1><2><3>" => array(1,2,3);
preg_match_all('/<(' . Group::FOLLOWERS . '|'. Group::MUTUALS . '|[0-9]+)>/', $ids, $matches, PREG_PATTERN_ORDER);