Adding a Decorator object to a vector

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C++

Hello,

I have a base class for a record, and want to add additional fields using decorators, and be able to chain the decorators (records can have an email, or a date of birth, or both, or none). I'm also going to have a lot of such decorators; one for each addtional field, and its comparison function. Once this is done, I'm going to add the objects to a vector, using a base class pointer.

Here's a precis of the code:

class BaseRecord
{
public:
	virtual bool Compare();		// defined elsewhere

protected:
	std::string m_strName;
	std::string m_strAddress:
};

class EmailDecorator : public BaseRecord
{
public:
	EmailDecorator(BaseRecord *pBase) : m_pBase(pBase){}

	bool Compare()
	{
		if (!CompareEmail())		// defined elsewhere
		{
			return false;
		}

		return m_pBase->Compare();
	}

protected:
	std::string m_strEmail

private:
	BaseRecord *m_pBase;
};

class DOBDecorator : public BaseRecord
{
public:
	DOBDecorator(BaseRecord *pBase) : m_pBase(pBase){}

	bool Compare()
	{
		if (!CompareDOB())		// defined elsewhere
		{
			return false;
		}

		return m_pBase->Compare();
	}

protected:
	std::string m_strDOB;

private:
	BaseRecord *m_pBase;
};

Those are the classes. I then want to do the following:

vector<BaseRecord *> m_vecRecords;

BaseRecord *pRecord = new BaseRecord();

// below is incorrect - copies only the pointer to the vector
m_vecRecords.push_back(pRecord);

// this is OK - default copy constructor used for BaseRecord
m_vecRecords.push_back(new BaseRecord(*pRecord));

// now chain the decorators

// pRecord is a BaseRecord
BaseRecord *pRecord = new EmailDecorator(pRecord);

// this is again incorrect - copies only pointer to the vector
m_vecRecords.push_back(pRecord);

// ??? what to do here - needs copy constructor for EmailDecorator
m_vecRecords.push_back(new EmailDecorator(*pRecord));

// pRecord is an EmailRecord
BaseRecord *pRecord = new DOBDecorator(pRecord);

// this is again incorrect - copies only pointer to the vector
m_vecRecords.push_back(pRecord);

// ??? what to do here - needs copy constructor for DOBDecorator
m_vecRecords.push_back(new DOBDecorator(*pRecord));

// Attempts at writing copy constructors

// should p be an EmailDecorator *p, or a BaseRecord *
EmailDecorator::EmailDecorator(const EmailDecorator *p)
{
// this wuill leak - no delete in the destructor
// in fact, there is no destructor
m_pBase = new BaseRecord(p);
m_strEmail = p->m_strEmail;
}

// should p be a DOBDecorator *, or  BaseRecord *
// in the above example, when the copy constructor is needed, it is an EmailRecord *
DOBDecorator::DOBDecorator(const DOBDecorator *p)
{
// this will leak - no delete in the destructor
// in fact, there is no destructor
m_pBase = new BaseRecord(p);
m_strDOB = p->m_strDOB;
}

So how do I write copy constructors for my decorators? It would appear that there must be a way to do what I want without even needing copy constructors.

Thanks for reading this. Any advice would be much appreciated.

Andy