Specific Class

[MrProfit]

Hello. I need to declare a class which must not allow making objects of it. I should not use virtual functions. Thank you in advance !

[Duthomhas]

You are talking about an abstract class.

You cannot make one without at least one pure virtual function.

Or a constructor that just raises an exception...

[MrProfit]

Thank you Duoas. Could you just explain me what "a constructor that just raises an exception" means ?

[Duthomhas]

class AlwaysFail
  {
  public:
    explicit AlwaysFail()
      {
      throw 0;
      }
  };

Such a class cannot be instantiated, since it throws an exception every time you try to create one.

[MrProfit]

O'kay, this works. But unfortunately, in my case that class should be base class. And the derived classes must allow making objects of them. Sorry , may be I've confused you by not saying the whole problem. Thanks again.

[Duthomhas]

I think you need to review the mechanics of inheritance. Either solution will work for your needs, though I suspect that if this is homework you are doing that your professor wants to see a pure virtual function in an abstract class.

[MrProfit]

:)
Yeah, it was a homework, but when it was gaven to us, we hadn't been taught nothing about virtual functions or abstract classes. That was the reason i wanted to avoid using pure virtual fuction. Anyway... thanks for your help!
Best wishes,
MrProfit