C++ Final or Sealed

Question

Consider the following class:

class X {
};

One can easily inherit from this:

class Y : public X {
};

Okay so far... Let's say we don't want anyone to inherit from Y we can then do this instead.

class Y sealed : public X {
};

Or we could do this:

class Y final : public X 
};

What are the main differences between the two keywords final and sealed? I know their basic purposes and what they are used for; I just wanted to know if there was anything specifically different between the two.

I don't see how this is a duplicate as I was asking the difference between the two and not so much if one is standard and one isn't; but it's all good. — Francis Cugler, Jun 24 '17 at 07:21
So, is it safe to say that if I have some `native` code that uses the MS specific keyword `sealed` and I want to make that code more portable I could then change `sealed` and replace it directly with `final` and that should do the job? — Francis Cugler, Jun 24 '17 at 07:28

score 7 · Accepted Answer · answered Jun 23 '17 at 09:27

7

sealed is not Standard C++ - it appears to be a Visual C++ CX extension. From that same page:

The ISO C++11 Standard language has the final keyword, which is supported in Visual Studio. Use final on standard classes, and sealed on ref classes.

answered Jun 23 '17 at 09:27

Vittorio Romeo

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Thank you for the information. Now I know that `final` is through the standard and `sealed` is MS specific, otherwise they do basically the same thing. – Francis Cugler Jun 23 '17 at 22:55

C++ Final or Sealed

1 Answers1