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Overloading operator and ostream

ben1355 (5)
In my program I'm trying to override == operator and also stream operator <<. I have some errors in these functions. Please help to fix my code. 

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 #include <iostream>
#include <string>
#include <iomanip>

using namespace std;

class Vehicle
{
public:
	Vehicle(double price = 0, int mpg = 0);
	void setPrice(double price);
	void setMpg(int mpg);
	double getPrice() const;
	int getMpg() const;
	void print() const;

private:
	double price;
	int mpg;
};

class Loan
{
public:
	Loan(string bank = "", double amount = 0);
	void setBank(string bank);
	void setAmount(double amount);
	string getBank() const;
	double getAmount() const;
	void print() const;

private:
	string bank;
	double amount;
};

class Car : public Vehicle
{
	friend ostream& operator<<(ostream&, const Car&);
public:
	Car(int nbrOfLoans = 2,

		double price = 0,
		int mpg = 0,

		string bank = "",
		double amount = 0,

		string name = ""
	);

	void setName(string name);
	string getName() const;
	void setLoan();
	Loan* getpLoan() const;
	void print() const;
	~Car();
	bool operator== (const Car&) const;

private:
	string name;
	Loan *pLoan;
	int nbrOfLoans;
};

Vehicle::Vehicle(double price, int mpg)
{
	Vehicle::price = price;
	Vehicle::mpg = mpg;
}

void Vehicle::setPrice(double price)
{
	Vehicle::price = price;
}

void Vehicle::setMpg(int mpg)
{
	Vehicle::mpg = mpg;
}

double Vehicle::getPrice() const
{
	return price;
}

int Vehicle::getMpg() const
{
	return mpg;
}

void Vehicle::print() const
{
	cout << "Price: " << price << endl;
	cout << "MPG: " << mpg << endl;
}


Loan::Loan(string bank, double amount)
{
	Loan::bank = bank;
	Loan::amount = amount;
}
void Loan::setBank(string bank)
{
	Loan::bank = bank;
}
void Loan::setAmount(double amount)
{
	Loan::amount = amount;
}
string Loan::getBank() const
{
	return bank;
}
double Loan::getAmount() const
{
	return amount;
}
void Loan::print() const
{
	cout << "Bank: " << bank << endl;
	cout << "Amount: " << amount << endl;
}


Car::Car(int nbrOfLoans,
	double price, int mpg,
	string bank, double amount,
	string name)
	:Vehicle(price, mpg)
{
	Car::name = name;
	Car::nbrOfLoans = nbrOfLoans;
	Car::pLoan = new Loan[nbrOfLoans];
}

Car::~Car()
{
	delete[]pLoan;
}

void Car::setName(string name)
{
	Car::name = name;
}
string Car::getName() const
{
	return name;
}
void Car::setLoan()
{
	double amount;
	string bank;

	for (int i = 0; i < nbrOfLoans; i++)

	{
		cout << "Enter bank and amount for loan " << i + 1 << ": ";
		cin >> bank >> amount;
		pLoan[i].setBank(bank);
		pLoan[i].setAmount(amount);
	}
}

Loan* Car::getpLoan() const
{
	return pLoan;
}

void Car::print() const
{
	Vehicle::print();

	for (int i = 0; i < nbrOfLoans; i++)
	{
		cout << endl << "Loan " << i + 1 << ": " << endl;
		pLoan[i].print();
		cout << endl;
	}

	cout << "Name: " << name << endl << endl;

	cout << fixed << showpoint << setprecision(1) << endl;
}

ostream& operator<<(ostream& os, const Car& car)
{
	Loan* pLoan = car.getpLoan();
	os << "Car name: " << car.name << endl
		<< "MPG: " << car.getMpg() << endl
		<< "Bank: " << pLoan[0].getBank();
	return os;
}

bool Car::operator== (const Car& car) const
{
	if (
		name = car.name
		&& pLoan[0].getAmount() == car.pLoan[0].getAmount
		&& pLoan[0].getBank() == car.pLoan[0].getBank
		&& getMpg() == car.getMpg()
		&& getPrice == car.getPrice
		)

		return true;
}


Severity Code Description Project File Line Suppression State
Error C3867 'Loan::getAmount': non-standard syntax; use '&' to create a pointer to member 205
Error C2446 '==': no conversion from 'double (__thiscall Loan::* )(void) const' to 'double' 205
Error C3867 'Loan::getBank': non-standard syntax; use '&' to create a pointer to member 206
Error C2679 binary '==': no operator found which takes a right-hand operand of type 'overloaded-function' (or there is no acceptable conversion) 206
Error C3867 'Vehicle::getPrice': non-standard syntax; use '&' to create a pointer to member 208
closed account (D80DSL3A)
The errors about non standard syntax are from how you're qualifying data members. You caused a name shadowing problem by naming the function parameters the same as the class data member names. eg.
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// example of poor coding practice causing problems
void Loan::setBank(string bank) 
{
	bank = bank;// ambiguous.Which is supposed to be which here?
}

Qualifying the data member should fix this, but Loan::bank would refer to a static class data member (your class has none), not a regular one.
Usethis->bank instead.
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void Loan::setBank(string bank) 
{
	this->bank = bank;// fixed
}

Or better yet, dodge the issue with a different argument name:
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void Loan::setBank(string Bank) 
{
	bank = Bank;// ambiguity be gone!
}

The other errors re no overload for ==...
maybe caused by lines 200, 201 where function calls are incomplete, eg:
car.pLoan[0].getAmount
should be
car.pLoan[0].getAmount()
ben1355 (5)
Thank you! it was very helpful and took off all the errors. Everything is fine except in my predefined variable (car1), I cannot get bank and amount in print and I just get name, MPG and price. Other variable (car2) is fine. Where is the problem?

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#include <iostream>
#include <string>
#include <iomanip>

using namespace std;

class Vehicle
{
public:
	Vehicle(double Price = 0, int Mpg = 0);
	void setPrice(double Price);
	void setMpg(int Mpg);
	double getPrice() const;
	int getMpg() const;
	void print() const;

private:
	double price;
	int mpg;
};

class Loan
{
public:
	Loan(string Bank = "", double Amount = 0);
	void setBank(string Bank);
	void setAmount(double Amount);
	string getBank() const;
	double getAmount() const;
	void print() const;

private:
	string bank;
	double amount;
};

class Car : public Vehicle
{
	friend ostream& operator<<(ostream&, const Car&);
public:
	Car(int nbrOfLoans = 2,

		double Price = 0,
		int Mpg = 0,

		string Bank = "",
		double Amount = 0,

		string Name = ""
	);

	void setName(string Name);
	string getName() const;
	void setLoan();
	Loan* getpLoan() const;
	void print() const;
	~Car();
	bool operator== (const Car&) const;

private:
	string name;
	Loan *pLoan;
	int nbrOfLoans;
};

Vehicle::Vehicle(double Price, int Mpg)
{
	price = Price;
	mpg = Mpg;
}

void Vehicle::setPrice(double Price)
{
	price = Price;
}

void Vehicle::setMpg(int Mpg)
{
	mpg = Mpg;
}

double Vehicle::getPrice() const
{
	return price;
}

int Vehicle::getMpg() const
{
	return mpg;
}

void Vehicle::print() const
{
	cout << "Price: " << price << endl;
	cout << "MPG: " << mpg << endl;
}


Loan::Loan(string Bank, double Amount)
{
	bank = Bank;
	amount = Amount;
}
void Loan::setBank(string Bank)
{
	bank = Bank;
}
void Loan::setAmount(double Amount)
{
	amount = Amount;
}
string Loan::getBank() const
{
	return bank;
}
double Loan::getAmount() const
{
	return amount;
}
void Loan::print() const
{
	cout << "Bank: " << bank << endl;
	cout << "Amount: " << amount << endl;
}


Car::Car(int nbrOfLoans,
	double Price, int Mpg,
	string Bank, double Amount,
	string Name)
	:Vehicle(Price, Mpg)
{
	name = Name;
	Car::nbrOfLoans = nbrOfLoans;
	pLoan = new Loan[nbrOfLoans];
}

Car::~Car()
{
	delete[]pLoan;
}

void Car::setName(string Name)
{
	name = Name;
}
string Car::getName() const
{
	return name;
}
void Car::setLoan()
{
	double Amount;
	string Bank;

	for (int i = 0; i < nbrOfLoans; i++)

	{
		cout << "Enter bank and amount for loan " << i + 1 << ": ";
		cin >> Bank >> Amount;
		pLoan[i].setBank(Bank);
		pLoan[i].setAmount(Amount);
	}
}

Loan* Car::getpLoan() const
{
	return pLoan;
}

void Car::print() const
{
	Vehicle::print();

	for (int i = 0; i < nbrOfLoans; i++)
	{
		cout << endl << "Loan " << i + 1 << ": " << endl;
		pLoan[i].print();
		cout << endl;
	}

	cout << "Name: " << name << endl << endl;

	cout << fixed << showpoint << setprecision(1) << endl;
}

ostream& operator<<(ostream& os, const Car& car)
{
	Loan* pLoan = car.getpLoan();
	os << "Car name: " << car.name << endl
		<< "MPG: " << car.getMpg() << endl
		<< "Bank: " << pLoan[0].getBank();
	return os;
}

bool Car::operator== (const Car& car) const
{
	if (
		name == car.name
		&& pLoan[0].getAmount() == car.pLoan[0].getAmount()
		&& pLoan[0].getBank() == car.pLoan[0].getBank()
		&& getMpg() == car.getMpg()
		&& getPrice() == car.getPrice()
		)

		return true;
}

int main()
{
	string name, bank;
	double price, amount;
	int mpg;

	Car car1(1, 24800.0, 22, "Citi", 21600, "Mustang");
	Car car2;
	Car *pCar1;
	Car *pCar2;

	pCar1 = &car1;
	pCar2 = &car2;

	pCar1->print();
	cout << endl;

	cout << "Enter name: ";
	cin >> name;
	cout << "Enter price: ";
	cin >> price;
	cout << "Enter MPG: ";
	cin >> mpg;

	pCar2->setLoan();
	pCar2->setPrice(price);
	pCar2->setMpg(mpg);
	pCar2->setName(name);

	pCar2->print();

	system("pause");
	return 0;
}
closed account (D80DSL3A)
I think you need to call setLoan() for each of the loans created at line 135 in Car constructor.
Also line 134 an old issue?
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Car::nbrOfLoans = nbrOfLoans;// No error? qualify as this->nbrOfLoans
pLoan = new Loan[nbrOfLoans];// default constructed
// loop and call setLoan() here

Glad that last post cleared all errors.
edit: An array of loans for 1 car? Sounds like a finance nightmare.
Last edited on
ben1355 (5)
When I try to call setLoan() it says class "Loan" has no member "setLoan"

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	Car::pLoan = new Loan[nbrOfLoans];
	for (int i = 0; i < nbrOfLoans; i++)
		pLoan[i].setLoan();
closed account (D80DSL3A)
Right. I guess it's a Car class member function, not a Loan class function.
I assumed wrong about that.
LOOK IT UP! In your own code, line 151 answers questions re. the setLoan function.
ben1355 (5)
I need more help, I don't get it. Sorry!
closed account (D80DSL3A)
It's ok. With some sleep now maybe I can get these crucial lines in the Car constructor right.
I see you chose to Capitalize argument names to distinguish them from the Car data members, but you missed 1 or 2, so need this->nbrOfLoans in:
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this->nbrOfLoans = nbrOfLoans;
pLoan = new Loan[nbrOfLoans];// default constructed
// call setLoan(). It loops through all loans
setLoan();

ben1355 (5)
OK, it solved half of the problem, but for my predefined car1 object, it asks foe bank and amount which I don't want to. Please check my main function too.

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#include <iostream>
#include <string>
#include <iomanip>

using namespace std;

class Vehicle
{
public:
	Vehicle(double myPrice = 0, int myMpg = 0);
	void setPrice(double myPrice);
	void setMpg(int myMpg);
	double getPrice() const;
	int getMpg() const;
	void print() const;

private:
	double price;
	int mpg;
};

class Loan
{
public:
	Loan(string myBank = "", double myAmount = 0);
	void setBank(string myBank);
	void setAmount(double myAmount);
	string getBank() const;
	double getAmount() const;
	void print() const;

private:
	string bank;
	double amount;
};

class Car : public Vehicle
{
	friend ostream& operator<<(ostream&, const Car&);
public:
	Car(int nol = 1,

		double myPrice = 0,
		int myMpg = 0,

		string myBank = "",
		double myAmount = 0,

		string myName = ""
	);

	void setName(string myName);
	string getName() const;
	void setLoan();
	Loan* getpLoan() const;
	void print() const;
	~Car();
	bool operator== (const Car&) const;

private:
	string name;
	Loan *pLoan;
	int nbrOfLoans;
};

Vehicle::Vehicle(double myPrice, int myMpg)
{
	price = myPrice;
	mpg = myMpg;
}

void Vehicle::setPrice(double myPrice)
{
	price = myPrice;
}

void Vehicle::setMpg(int myMpg)
{
	mpg = myMpg;
}

double Vehicle::getPrice() const
{
	return price;
}

int Vehicle::getMpg() const
{
	return mpg;
}

void Vehicle::print() const
{
	cout << "Price: " << price << endl;
	cout << "MPG: " << mpg ;
}


Loan::Loan(string myBank, double myAmount)
{
	bank = myBank;
	amount = myAmount;
}
void Loan::setBank(string myBank)
{
	bank = myBank;
}
void Loan::setAmount(double myAmount)
{
	amount = myAmount;
}
string Loan::getBank() const
{
	return bank;
}
double Loan::getAmount() const
{
	return amount;
}
void Loan::print() const
{
	cout << "Bank: " << bank << endl;
	cout << "Amount: " << amount;
}


Car::Car(int nol,
	double myPrice, int myMpg,
	string myBank, double myAmount,
	string myName)
	:Vehicle(myPrice, myMpg)
{
	name = myName;
	nbrOfLoans = nol;
	pLoan = new Loan[nbrOfLoans];
	setLoan();
}

Car::~Car()
{
	delete[]pLoan;
}

void Car::setName(string myName)
{
	name = myName;
}
string Car::getName() const
{
	return name;
}
void Car::setLoan()
{
	double myAmount;
	string myBank;

	for (int i = 0; i < nbrOfLoans; i++)
	{
		cout << "Enter bank and amount for loan " << i + 1 << ": ";
		cin >> myBank >> myAmount;
		pLoan[i].setBank(myBank);
		pLoan[i].setAmount(myAmount);
	}
}

Loan* Car::getpLoan() const
{
	return pLoan;
}

void Car::print() const
{
	Vehicle::print();

	for (int i = 0; i < nbrOfLoans; i++)
	{
		cout << endl << "Loan " << i + 1 << ": " << endl;
		pLoan[i].print();
		cout << endl;
	}

	cout << "Name: " << name << endl << endl;

	cout << fixed << showpoint << setprecision(1) << endl;
}

ostream& operator<<(ostream& os, const Car& car)
{
	Loan* pLoan = car.getpLoan();
	os << "Price: " << car.getPrice() << endl
		<< "MPG: " << car.getMpg() << endl
		<< "Bank: " << pLoan[0].getBank() << endl
		<< "Amount: " << pLoan[0].getAmount() << endl
		<< "Car name: " << car.name << endl;
		
		
	return os;
}

bool Car::operator== (const Car& car) const
{
	if (
		name == car.name
		&& pLoan[0].getAmount() == car.pLoan[0].getAmount()
		&& pLoan[0].getBank() == car.pLoan[0].getBank()
		&& getMpg() == car.getMpg()
		&& getPrice() == car.getPrice()
		)

		return true;
}

int main()
{
	string name, bank;
	double price, amount;
	int mpg;

	Car car1(1, 24800.0, 22, "Citi", 21600, "Mustang");
	Car car2;
	Car *pCar1;
	Car *pCar2;

	pCar1 = &car1;
	pCar2 = &car2;

	cout << *pCar1 <<endl;
	cout << endl;

	cout << "Enter name: ";
	cin >> name;
	cout << "Enter price: ";
	cin >> price;
	cout << "Enter MPG: ";
	cin >> mpg;

	pCar2->setLoan();
	pCar2->setPrice(price);
	pCar2->setMpg(mpg);
	pCar2->setName(name);

	cout << *pCar2 << endl;

	cout << "Are this cars similar?" << endl;
	if (*pCar1 == *pCar2)
		cout << "Cars are similar." << endl;
	else
		cout << "Cars are different." << endl;

	system("pause");
	return 0;
}
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