errors with virtual functions

I have declared these classes, as below, but I get repeatedly the following compile errors. Could you explain to me what is wrong?

Code:

---

class A{
      public:
            virtual void f1();
};

class A1: public A{
      public:
        void f1();
};

class A2: public A{
      public:
        void f1();
};

---

Code:

---

variable or field `f1' declared void
`f1' declared as a `virtual' field
 expected `;' before '(' token

---

what compiler are you using? i would have expected a different error so perhaps something else is going on that you have not posted, but in any case if you declare a virtual function then you also have to provide an implementation, so just place a pair of curly braces after the declaration in your class definition

Quote:

---

Originally Posted by rogster001

what compiler are you using? i would have expected a different error so perhaps something else is going on that you have not posted, but in any case if you declare a virtual function then you also have to provide an implementation, so just place a pair of curly braces after the declaration in your class definition

---

I am using the Dev C++. I have also provided the virtual functions implementations along with the child class definitions. I just removed them, when posting the code.

The only way to get that message is to have

Code:

---

virtual void f1;

---

instead of

Code:

---

virtual void f1();

---

The missing ; probably just brings the point home that you need to check your parentheses and braces and make sure they line up where they're supposed to.

I'm not sure what the problem is but MinGW GCC 4.5 can compile your code as is. To get the same amazing result, you could just upgrade your compiler (which means throwing Dev-C++ away probably) and try this orthis .

I am using the Dev C++ (vc 2005 TooL), can compile your code .

Well, I had to test another compiler simply (Microsoft visual C++ 2010).