member_functions.cpp

来自「ThinkingC++中文版」· C++ 代码 · 共 72 行

#include <iostream>
using namespace std;

// Member functions (implicit "this"):
class Byte {
  unsigned char b;
public:
  Byte(unsigned char bb = 0) : b(bb) {}
  // No side effects: const member function:
  const Byte& operator+() const {
    cout << "+Byte\n";
    return *this;
  }
  const Byte operator-() const {
    cout << "-Byte\n";
    return Byte(-b);
  }
  const Byte operator~() const {
    cout << "~Byte\n";
    return Byte(~b);
  }
  Byte operator!() const {
    cout << "!Byte\n";
    return Byte(!b);
  }
  Byte* operator&() {
    cout << "&Byte\n";
    return this;
  }
  // Side effects: non-const member function:
  const Byte& operator++() { // Prefix
    cout << "++Byte\n";
    b++;
    return *this;
  }
  const Byte operator++(int) { // Postfix
    cout << "Byte++\n";
    Byte before(b);
    b++;
    return before;
  }
  const Byte& operator--() { // Prefix
    cout << "--Byte\n";
    --b;
    return *this;
  }
  const Byte operator--(int) { // Postfix
    cout << "Byte--\n";
    Byte before(b);
    --b;
    return before;
  }
};

void g(Byte b) {
  +b; //call member function: b.operator+();
  -b;
  ~b;
  Byte* bp = &b;
  !b;
  ++b;
  b++;
  --b;
  b--;
}

void main() {
//  Integer a;
  //f(a);
  Byte b;
  g(b);
} ///:~