virtual

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Original post by luasitdown because I add a virtual function in base class, I need add implementation in all derived class.

Quote:

Original post by Sneftel Quote: Original post by luasitdown because I add a virtual function in base class, I need add implementation in all derived class. No you don't. You only need that if you've declared it as pure virtual. And then, the compiler will straight-out tell you which classes don't yet have it.

struct A{	~A(){std::cout<<"dead\n";}virtual aa();	int i;	char c;	long l;};class B:public A{};A *a = new A; // here LNK error