protected function throwNewInvalidArgumentException ($errorMsg) {
		$msgs = [];
		if ($this->field) 
			$msgs[] = 'Field name: `'.$this->field->GetName() . '`, Field type: `'.get_class($this->field).'`';
		if ($this->form) 
			$msgs[] = 'Form id: `'.$this->form->GetId() . '`, Form type: `'.get_class($this->form).'`';
		$selfClass = version_compare(PHP_VERSION, '5.5', '>') ? self::class : __CLASS__;
		throw new \InvalidArgumentException(
			'['.$selfClass.'] ' . $errorMsg . ($msgs ? ' '.implode(', ', $msgs) : '')
		);
	}