overloading operator <<

[noob2c]

hi, i overloaded the operator << as a friend function in this class, and when i compile the program i get this error:-
\customerType.cpp(90): error C2065: 'vtl' : undeclared identifier

as a friend function doesnt it have access to all private/protected members. Here is the code......what am i doing wrong?

customerType.h

#ifndef H_CUSTOMERTYPE
#define H_CUSTOMERTYPE

#include<iostream>
#include<string>
#include<list>

using namespace std;

class customerType
{
	friend ostream& operator<<(ostream&, const customerType&);
protected:
	string name;
	int numCheckedOut;
	list<string> vtl;

public:
	bool operator < (const customerType& )const;//defined
	bool operator == (const customerType& )const;//defined
	void printCustomerName()const;//defined
	void addTitle(string);
	void removeTitle(string);
	bool matchName(string);
	void printCustomerTitles();
	void setName(string);
	void setNumCheckedOut(int);
	customerType(string);
	customerType();
	void removeAllTitles();
	string getName()const;
	int numberChecked()const;
};

#endif

customerType.cpp

#include "customerType.h"
#include<list>
#include<iostream>

using namespace std;

bool customerType::operator < (const customerType& other)const
{
	return (name < other.name);
}

bool customerType::operator == (const customerType& other)const
{
	return (name == other.name);
}

void customerType::printCustomerName()const
{
	cout<<"Customer Name: "<<name<<endl;
}

void customerType::addTitle(string mName)
{
	vtl.push_back(mName);
	numCheckedOut++;
}

void customerType::removeTitle(string mName)
{
	vtl.remove(mName);
	numCheckedOut--;
}

bool customerType::matchName(string Cname)
{
	return( name == Cname );
}

void customerType::printCustomerTitles()
{
	list<string>::const_iterator video;

	for(video=vtl.begin();video!=vtl.end();video++)cout<<"Movie Name: " << *video<<endl;
}

void customerType::setName(string Cname)
{
	name=Cname;
}

void customerType::setNumCheckedOut(int num)
{
	numCheckedOut=num;
}

customerType::customerType(string cName)
{	
	name=cName;
	numCheckedOut=0;
	
}

customerType::customerType()
{
	name="";
	numCheckedOut=0;
}

void customerType::removeAllTitles()
{
	for(int i=0;i<numCheckedOut;i++)vtl.pop_back();
	numCheckedOut=0;
}

string customerType::getName()const
{
	return name;
}

int customerType::numberChecked()const
{
	return numCheckedOut;
}

ostream& operator<<(ostream& os, const customerType& customer)
{
	list<string>::const_iterator location;
	os<<customer.name;
	os<<customer.numCheckedOut;
	for(location= vtl.begin();location!=vtl.end();location++)
	{
		os<<*location<<endl;
	}
	return os;
}

[joshdick]

I think it needs to be customer.vtl in order for you to access that variable.

[elad]

by default all members of a class are private. Therefore the friend function you have declared has private access, meaning it can only be accessed by a public member function. I would try declaring the friend function with public access so it is available to any function.

[lyx]

joshdick is right, a friend function does have acces to members even if they are privates or protected. But they are not members thus they don't have a this pointer.

elad, I think what you are saying is wrong; as friends do not have the class scope, they do not have the access limitations of the class neither.

[elad]

I agree with the customer.vtl requirement.

With re friend functions I know friend functions don't have access to the this ponter of object to which they are a friend, just access to the data members, but I don't know about scope. Never thought of it actually because I've never seen a friend function declared as private, they've always been public so I just assumed that they were declared so for the same reason other methods are declared public. Live and learn.