access private members in inheritance

c++ inheritance private
ofer picture ofer · Nov 23, 2011 · Viewed 70.6k times · Source

I have a class A, which have a field val declared as private. I want to declare a class B, that inherit from A and have an access to val. Is there a way to do it on C++?

I want to do it because I need to overload some functions of A, without changing A code at all.

Thanks.

Answer

Constantinius picture Constantinius · Nov 23, 2011

Quick answer: You don't. Thats what the protected key-word is for, which you want to use if you want to grant access to subclasses but no-one else.

private means that no-one has access to those variables, not even subclasses.

If you cannot change code in A at all, maybe there is a public/protected access method for that variable. Otherwise these variables are not meant to be accessed from subclasses and only hacks can help (which I don't encourage!).

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