nested class has special capabilities ] C++^java

Q: Can nested class (NN) methods access a private member of the enclosing class EE? See c++nested class accessing host private member

Can EE methods access NN’s private members? Yes. Tested. See below.

Below is based on P186 ARM, perhaps outdated.
Q: in terms of syntax, how does Inner class methods refer to Outer class’s non-static[1] field?
A: no special access. Unlike java, there’s no hidden “this” field pointing to the Outer _i n s t a n c e_
A: yes if the Inner method has a pointer, reference or a nonref variable of an Outer class _i n s t a n c e_,

Java’s nested class N1 is in the same “private club” along with E2() an Enclose class private method.
– N1 methods can access private members of E2
– E2 methods can access private members of N1
–> Not in C++

Q: So what special capabilities does a nested class has? Why make a class nested at all?
A: to mention the “Inner” type name, you need to prefix it as “Outer::Inner”
A: another specialness — inner class methods can access outer private members. As pointed out on
— in the original C++98 the inner class has no special privileges accessing the outer class.With C++98 compiler you’d either have to give the inner class the necessary privileges (friendship) or expose
the outer members x and y as public. However, this situation was classified as a defect in C++98, and it was decided that inner classes should have full access to outer class members (even private ones).

[1] static is fine — Outer::f


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