public static function can_mark_all_messages_as_read(int $userid, int $conversationid) : bool {
        global $USER;

        $systemcontext = \context_system::instance();

        if (has_capability('moodle/site:readallmessages', $systemcontext)) {
            return true;
        }

        if (!self::is_user_in_conversation($userid, $conversationid)) {
            return false;
        }

        if ($USER->id == $userid) {
            return true;
        }

        return false;
    }
public static function can_mark_all_messages_as_read(int $userid, int $conversationid) : bool {
        global $USER;

        $systemcontext = \context_system::instance();

        if (has_capability('moodle/site:readallmessages', $systemcontext)) {
            return true;
        }

        if (!self::is_user_in_conversation($userid, $conversationid)) {
            return false;
        }

        if ($USER->id == $userid) {
            return true;
        }

        return false;
    }
public static function can_mark_all_messages_as_read ( int $ userid , int $ conversationid ) : bool { global $ USER ; $ systemcontext = \ context_system :: instance ( ) ; if ( has_capability ( 'moodle/site:readallmessages' , $ systemcontext ) ) { return true ; } if ( ! self :: is_user_in_conversation ( $ userid , $ conversationid ) ) { return false ; } if ( $ USER -> id == $ userid ) { return true ; } return false ; }
Checks if a user can mark all messages as read.

@param int $userid The user id of who we want to mark the messages for
@param int $conversationid The id of the conversation
@return bool true if user is permitted, false otherwise
@since 3.6
Checks if a user can mark all messages as read .