重载operator<< operator==和operator!=

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必须重载operator<<、operator==和operator!=

.h文件和.cpp文件包含在下面：

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);
  }

我收到以下编译错误：

../src/hw4.cpp:71:错误：'c1 <<“** *\012"‘../src/Complex.h:54:注意:候选项为: std::ostream& JoePitz::operator<<( std::ostream&，const bool&) ../src/Complex.h:53:注意:std：：ostream& JoePitz::operator<<(std::ostream&，const JoePitz::Complex&)

据我所知，这是因为不知道要实现哪个重载函数。

我遇到的问题是如何处理这样一个事实: operator<<函数返回一个ostream并接受一个复杂对象，而operator==函数返回一个bool。

但是我不知道如何更改operator==函数来处理布尔和/或复杂对象。我试图添加另一个重载的返回布尔值的opperator<<函数，但编译器仍然有问题。

任何帮助都将不胜感激。

Answer 1

这是一个简单的运算符优先级错误，这是

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

应该是这样的

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

<<比==具有更高的优先级，因此您需要使用括号。

删除ostream bool过载。

另一个变化

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

都应该是const方法

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