On Monday, 13 June 2022 at 09:09:08 UTC, user1234 wrote:

well the online compilers are too old, but if you try this code with a more recent compiler

{$MODE OBJFPC}{$H+}
{$MODESWITCH ADVANCEDRECORDS}
type TS = record
  private
    a: integer;
  strict private
    b: integer;
end;

var
 s: TS;

begin
  s.a := 1; // OK
  s.b := 1; // NG
end.

this gives

On Monday, 13 June 2022 at 09:11:42 UTC, Ola Fosheim Grøstad wrote:

No, it does not follow in this case. A subclass does not have access to the private members of the superclass in D unless they are declared in the same module. So what that code is doing is saying, "Hey Bar, give me this field that you don't have access to."

On Monday, 13 June 2022 at 09:34:46 UTC, Mike Parker wrote:

It wasn't the subclass that tried to access, it was the owner of the subclass, the module.

If the owner of Cyborgs have direct access to the brain that all Cyborgs possess, then it follows that it also must have direct access to the brain of PinkCyborgs too without having to call it a Cyborg. A PinkCyborg is also a Cyborg.

If a surgeon can operate directly on the brain of a Human, then it follows that he also should be able to operate directly on the brain of Men and Women, without having to claim that they are just Humans to him (and that he does not care about their gender specific attributes). Men and Women are undeniably Human. It should not matter whether the Ambulance personell says "this is a Man" or "this is a Human".

On Monday, 13 June 2022 at 10:03:59 UTC, Ola Fosheim Grøstad wrote:

Typo: "it was the owner of the super class, the module."

On Monday, 13 June 2022 at 10:03:59 UTC, Ola Fosheim Grøstad wrote:

Through the subclass.

I'm a Parker. My father is a Parker. But if you ask me for the contents of my father's safe, and I don't have the combination, then you aren't getting the contents of my father's safe. Ask me to put you in touch with my father though, and you can work something out.

It's all about the interface here. An instance of B is an A only in terms of the public (and protected) interface. It doesn't have access to A's private members if it isn't declared in the same module, so you can't get A's private members through an instance of B. You have to cast to A.

This doesn't allow access either:

module ca;

import cb;

class A {
    private int _x;

    protected void modX(B b) {
        b._x = 10;
    }
}

---

module cb;

import ca;

class B : A {
    void setX() { modX(this); }
}

void main() {
    B b = new B;
    b.setX;
}

On Monday, 13 June 2022 at 10:13:30 UTC, Mike Parker wrote:

No. You have direct access.

This is not an example of inheritance. Inheritance is a subtyping relation.

If you let the Surgeon module own the Human blueprint and direct access to all the brains of all Humans, then it follows that the Surgeon module has to be given direct access to all Humans whether you know if that Human also is a Woman or not.

Keep in mind that there are no pure Humans in the real world, only Men or Women (or some other gendered variations). The fact that we can instance Humans does not mean that they are not Women or Men. It means that we don't care (or know) whether they are Women or Men when we give them a computer representation.

On Monday, 13 June 2022 at 10:13:30 UTC, Mike Parker wrote:

Look, I'm not against the logic, I completely understand it from the perspective of that a subclass shouldn't have access to private members of the class it inherits from, BUT remember in D private doesn't mean private to the class, so the symbol should only be private when accessed from anywhere but the module.

On Monday, 13 June 2022 at 10:43:09 UTC, bauss wrote:

To add on to this; it's not a matter of what's more logical, but simply that D is contradicting itself, so either D stops being referred to as "module private" or this will be deemed an unfinished feature/bug.