struct bar;
struct foo
{
   operator bar*();
   auto operator<=>(const foo& rhs) const = default;
};

class Foo {
   Foo operator       +(const Foo& rhs) const;

   const Foo& operator==(Foo& me);

   bool operator      >(const Foo& rhs) const;

   InStream& operator <<(InStream& in);
}

const Foo& Foo::operator==(Foo& me)
{
}

Foo Foo::operator+(const Foo& rhs) const
{
}

bool Foo::operator>(const Foo& rhs) const
{
}

class Example
{
   char                  m_array[256];

   Example& operator     =(const Example& rhs);
   Example& operator     +=(const Example& rhs);
   const Example operator+(const Example& other) const;
   bool operator         ==(const Example& other) const;
   bool operator         !=(const Example& other) const;
   Example operator      +(const Example& x, const Example& y);
   Example operator      *(const Example& x, const Example& y);

   double& operator      ()(int row, int col);
   double operator       ()(int row, int col) const;
   void operator         ++();
   int& operator         *();
   Example& operator     ++();    // prefix ++
   Example operator      ++(int); // postfix ++

   bool operator         <(const Example& lhs, const Example& rhs) const;

   int operator()(int index)
   {
      i = ~~3;
      return index + 1;
   }

   char& operator[](unsigned i)
   {
      return m_array[i & 0xff];
   }
}
bool Example::operator==(const Example& other) const
{
   /*TODO: compare something? */
   return false;
}
bool Example::operator!=(const Example& other) const
{
   return !operator==(other);
}


void a() {
   Op op = &X::operator==;
   if (!A)
      if (op != &X::operator==)
	 A(1) = a;
   if (!A) {
      if (op != &X::operator==)
	 A(1) = a;
   }
}

void *operator new(std::size_t) throw(std::bad_alloc);
void *operator new[](std::size_t) throw(std::bad_alloc);
void operator  delete(void *) throw();
void operator  delete[](void *) throw();