public function isPresenceRequired($validatePresent = null)
    {
        if ($validatePresent === null) {
            return $this->_validatePresent;
        }

        deprecationWarning(
            'ValidationSet::isPresenceRequired() is deprecated as a setter. ' .
            'Use ValidationSet::requirePresence() instead.'
        );

        return $this->requirePresence($validatePresent);
    }