Why do private member variables behaved like protected in the same module when creating deriving class?

[Neia Neutuladh]

On Tue, 30 Oct 2018 06:49:38 +0000, unprotected-entity wrote:
> Why doesn't D treat const, within a module, the same way it treats
> private?
> 
> I'm mean, either we're all friends, or we're not - which is it?
> 
> -------------
> class Plane {
>      // private const int MAX_SPEED = 1000;
>      //
>      // bummer, my friends below can't change MAX_SPEED - it's
> const.

const prevents *anything* from altering the value through that variable. 
const-correctness is orthogonal to encapsulation.