重载operator << operator ==和operator！=

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必须重载operator <<，operator ==和operator！=

.h文件和.cpp文件包括在下面：

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 <<“中没有匹配'operator <<'* * * * 012”'../src/Complex.h:54：注意：候选人是： std :: ostream＆JoePitz :: operator <<（std :: ostream＆，const bool＆）../ src /Complex.h：53：注意：std :: ostream＆JoePitz :: operator <<（std :: ostream＆，const JoePitz ：：复杂＆）

根据我的理解，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operator <<函数返回一个ostream并接受一个Complex对象这一事实，但是operator == function返回一个bool。

但我不知道如何更改operator ==函数来处理bool和/或Complex对象。 我试图添加另一个重载的opperator <<函数返回一个bool但编译器仍然有问题。

任何帮助将不胜感激。

Answer 1

这是一个简单的运算符优先级错误，这个

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

应该是这个

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

<<具有比==更高的优先级，因此您需要括号。

删除ostream bool重载。

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);

应该都是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;