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loic.actarus.joly@numeric · Guest

Hello, and happy new year !

I recently came upon some code like this:

class A
{
protected:
int f();
};

class B : public A
{
typedef int(A::*fptr)();
fptr p;
int g()
{
//p = &A::f;
p = &B::f;
}
};

If I remove the comment, I get a compilation error, which is normal
according to the standard :

11.5 Protected member access
When a friend or a member function of a derived class references a
protected nonstatic member of a base class, an access check applies in
addition to those described earlier in this clause.[...] If the
access is to form a pointer to member, the nested-name-specifier shall
name the derived class (or any class derived from that class).

I just wonder what can be the reason of this rule. I tried looking in
the D&E, without success, so I come to you in hope of some explanation.

Best regards,

--
Loïc Joly

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