Re: Restricting access should be illegal?
Walter Bright wrote:
#include <stdio.h>
class A {
public:
virtual void Member() { printf("A::Member\n"); }
};
class B : public A {
private:
virtual void Member() { printf("B::Member\n"); }
};
int main()
{
B *b = new B();
// b->Member(); // error, B::Member is private
A *a = b;
a->Member(); // calls B::Member
}
-------------------------
Shouldn't restricting access to an overriding virtual function be an
error? After all, we can get at it anyway via an implicit conversion.
Does anyone know of a legitimate design pattern that does this?
I can't believe that this question still pops up after all these years
of having been beaten to death. Googling for "private interface" should
yield convincing arguments for why keeping virtual dispatch and access
level orthogonal is desirable.
--
Gerhard Menzl
#dogma int main ()
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