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Accessing private member of a class through type-casting

Consider the code

class A {
private:
int a;
};

int main(void) {
A x;
int* ptr = (int*)&x;
*x = 10;
return 0;
}

I understand that I can not change the private attributes of a class,
but what does standard have to say about the code above?

Apr 7 '06
31 3206

Tomás wrote:
If I was on a
MS Windows programming newsgroup, I'd conceed that there's nothing wrong
with storing an object's address in an integral type.


That is also necessary on other platforms. It is the whole reason the
standard guarantees that casting from one pointer type to the other and
back results in the same pointer value...given certain implementation
defined requirements that the programmer is expected to know. It is a
valid technique (necessary when dealing with any C based api), it is
topical, and it is in the standard.

Apr 8 '06 #31
Why would you want to? Reading the replies above, it's could be quite
unsafe to do that.

Reflection is what you need...

Apr 15 '06 #32

This thread has been closed and replies have been disabled. Please start a new discussion.

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