C++ 之 auto推导遇到多态

#include 

using namespace std;

class base {
public:
    virtual void fun() {
        std::cout << "base::fun()" << std::endl;
    }
};

class Derived : public base {
public:
    virtual void fun() {
        std::cout << "Derived::fun()" << std::endl;
    }
};

int main(int argc, char *argv[]) {
    base* d = new Derived;
    std::cout << " d->fun() call: ";
    d->fun(); // Derived::fun()
    
    auto b = *d;
    std::cout << " b.fun() call: ";
    b.fun(); // base::fun()
    
    auto &bb = *d;
    std::cout << " bb.fun() call: ";
    bb.fun(); // Derived::fun()
    
    auto bbb = d;
    std::cout << " bbb->fun() call: ";
    bbb->fun(); // Derived::fun()
}

输出结果是：

 d->fun() call: Derived::fun()
 b.fun() call: base::fun()
 bb.fun() call: Derived::fun()
 bbb->fun() call: Derived::fun()