slice.cpp

来自「Thinking in C++ 2nd edition source code 」· C++ 代码 · 共 35 行

//: C15:Slice.cpp
// From Thinking in C++, 2nd Edition
// at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Object slicing
#include <iostream>
using namespace std;

class Base {
  int i;
public:
  Base(int I = 0) : i(I) {}
  virtual int sum() const { return i; }
};

class Derived : public Base {
  int j;
public:
  Derived(int I = 0, int J = 0)
    : Base(I), j(J) {}
  int sum() const { return Base::sum() + j; }
};

void call(Base b) {
  cout << "sum = " << b.sum() << endl;
}

int main() {
  Base b(10);
  Derived d(10, 47);
  call(b);
  call(d);
} ///:~