1 2 3class test 4{ 5public: 6 virtual void aa() {} 7 8 int f; 9}; 10 11class testsub : public test 12{ 13public: 14 testsub() : g(0) {} 15 virtual void aa() {} 16 17 int g; 18}; 19 20 21class testsubother : public test 22{ 23public: 24 testsubother() : h(0) {} 25 virtual void aa() {} 26 27 int h; 28}; 29 30extern test* maketestsub(); 31 32extern bool istestsub(test* t);