Non-ugly ways to implement a 'static' class or namespace?

ProtectAndHide ProtectAndHide at gmail.com
Thu Feb 16 02:50:23 UTC 2023


On Thursday, 16 February 2023 at 02:26:44 UTC, Mike Parker wrote:
> On Wednesday, 15 February 2023 at 20:10:31 UTC, ProtectAndHide 
> wrote:
>
>>
>> What Mike is arguing, is that I don't need a 'data hiding' 
>> mechanism for a user-defined type, because that is already 
>> provided to me by the 'data hiding' mechanism of the module.
>>
>> That is his argument.
>>
>> My argument is that I want 'data hiding' mechanism at the 
>> user-defined type level as well.
>>
>> Again, his argument is that i don't need it.. because...
>>
>>
>
> Wrong. I'm arguing  things:
>
> 1. D has encapsulation (you say it doesn't).
> 2. We don't need a new protection attribute or a redefinition 
> of private because D already provides the mechanism to give you 
> what you want.

Honestly. How hard is it for you to accept? It's so simple I 
could explain it to first year programmer!

It's really straight forward, obvious, correct, and can be 
demonstrated like this:

// foo type has no ability (at the type level)
// to hide anything from other code in the module.
// this is fact. I'm not making it up!
// There is nothing to argue against here. It's just fact.

module test;
@safe:

import std;

class foo { private int x = 10; } // C++, C#, Swift, 
Javascript...programmers - beware!

void main()
{
     foo f = new foo;

     f.x = 20; // D provides no way to prevent this from occuring 
as there is no mechanism at the type level to do this. Instead 
you have to put foo in a module by itself, so no other code can 
access x. So EVERY user-defined type that wants data hiding from 
users of that type (including other code in the module using that 
type), must be in its own module.


     writeln(f.x);
}


I understand your argument completely. Just put foo in its own 
module. I get it.

What you don't get, is that I want such design decisions to be in 
my hands, and not yours.

That is, I want a mechanism at the type level as well.

You don't want me to have that. Well fine.

But at stop mispresenting what I'm saying. What I've stated 
above, is what I'm saying.. no more.. no less.




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