overloading operator<< operator== and operator!=

Question

Homework assignment

Have to overload both the operator<<, operator== and operator!=

.h file and .cpp file is included below:

namespace JoePitz
{
 class Complex
 {
 // declare friend functions
 friend ostream &operator<<(ostream &out, const Complex &value);
 friend ostream &operator<<(ostream &out, const bool &value);
 friend istream &operator>>(istream &in, Complex &value);
 public:
 // constructor
 Complex(double real, double imaginary);
 // overloading +/-/==/!= operators
 Complex operator+(const Complex &compx2);
 Complex operator-(const Complex &compx2);
 bool operator==(const Complex &compx2);
 bool operator!=(const Complex &compx2);
 private:
 double real;
 double imaginary;
 void initialize(double real, double imaginary);
 };
 // GCC requires friend functions to be declared in name space
 ostream &operator<<(ostream &out, const Complex &value);
 ostream &operator<<(ostream &out, const bool &value);
 istream &operator>>(istream &in, Complex &value);
}
 excerpt from .cpp file
 ostream& JoePitz::operator<<(ostream &out, const Complex &value)
 {
 // print real
 cout << value.real;
 // print imaginary
 if (value.imaginary == ISZERO)
 {
 cout << POSSIGN << value.imaginary << IMAGNSGN;
 }
 else if (value.imaginary > ISZERO)
 {
 cout << POSSIGN << value.imaginary << IMAGNSGN;
 }
 else
 {
 cout << value.imaginary << IMAGNSGN;
 }
 return out;
 }
 ostream& JoePitz::operator<<(ostream &out, const bool &value)
 {
 return out;
 }
 // overloaded == operator
 bool JoePitz::Complex::operator==(const Complex &compx2)
 {
 return (this->real == compx2.real && this->imaginary == compx2.imaginary);
 }
 // overloaded != operator
 bool JoePitz::Complex::operator!=(const Complex &compx2)
 {
 return !(this->real == compx2.real && this->imaginary == compx2.imaginary);
 }

I received the following compile error:

../src/hw4.cpp:71: error: no match for 'operator<<' in 'c1 << " * * *012円"' ../src/Complex.h:54: note: candidates are: std::ostream& JoePitz::operator<<(std::ostream&, const bool&) ../src/Complex.h:53: note: std::ostream& JoePitz::operator<<(std::ostream&, const JoePitz::Complex&)

From my understanding this is a result from not knowing which overloaded function to implement.

The problem I am having is how to deal with the fact that the operator<< function return an ostream and accepts a Complex object, but the operator== function return a bool.

But I do not know how to change the operator== function to handle the bool and or the Complex object. I have attempted to add another overloaded opperator<< function that return a bool but the compiler still has problems with it.

Any assistance will be greatly appreciated.

• Qaz: Where is the error happening?
• huskerchad: And what are the types/values of POSSIGN/IMAGNSGN? Furthermore, it's not clear why you're overloading the ostream/bool pair for operator<< (especially given that your overload does nothing).
• japreiss: Please share the code that actually produces the error. The line numbers of your error message don't correspond with the sample you posted. Even better, post an SSCCE.
• Joe Pitz: The code that produces the error is: cout << "* * * Unit Test 3 comparison operations == != * * \n"; cout << " * * Print c1 == c1 = " << c1 == c1 << " * * *\n"
• Joe Pitz: const char POSSIGN = '+'; const char NEGSIGN = '-'; const char IMAGNSGN = 'i'; const double ISZERO = 0.0

Answer 1

It's a simple operator precedence error, this

cout << "* * * Unit Test 3 comparison operations == != * * \n";
cout << " * * Print c1 == c1 = " << c1 == c1 << " * * *\n";

should be this

cout << "* * * Unit Test 3 comparison operations == != * * \n";
cout << " * * Print c1 == c1 = " << (c1 == c1) << " * * *\n";

<< has higher precedence than == so you need the brackets.

Remove the ostream bool overload.

Another change

 Complex operator+(const Complex &compx2);
 Complex operator-(const Complex &compx2);
 bool operator==(const Complex &compx2);
 bool operator!=(const Complex &compx2);

should all be const methods

 Complex operator+(const Complex &compx2) const;
 Complex operator-(const Complex &compx2) const;
 bool operator==(const Complex &compx2) const;
 bool operator!=(const Complex &compx2) const;