On Friday, 18 May 2018 at 15:57:06 UTC, bachmeier wrote:
class A {
private int x;
private(this) int y;
}
Instead of such a syntax if this ever comes to be, we could just
introduce a new keyword into the language.
class A {
private int x;
closed int y; //closed for acces outside this class.
owned int z; //owned by this class.
inside int zz; //only accessible inside this class.
}
As far as I can tell we don't need a `private(this)` or
`private(classname)` declaration. I'd much rather have a keyword
specifically designed for the thing that it does.
D is at the point that there's already legacy code so you can't
use the `private` keyword anymore whitout doing something funky
with defining it private to class scope any other given scope. It
would also raise the question of "Why can't I have
`private(functionName)`? Does that make sense?"
I do see how this could be usefull if you had a 6000 line static
function that you don't want to have access to a private member
that is defined in thesame module. But then again, one could
simply extract it to its own module, reference the former module
and use those classes.
I personally find having no class private members incredibly
usefull since I can use them for unittests that way.
Then I can enforce the existance of a class member regardless of
its scope to exist and therefore enforce the use of a given
approach to the problem a class is solving.
While you might say that a unittest shouldn't acces private
members and only public members, there are plenty of testcases
where one would want to write a unittest to set a given variable
via public function and then test if the appropriate private
fields are properly set. While this sounds like a trivial usecase
I believe it to be a verry big one in practice since it removes a
lot of boilerplate code from your unit-tests, together with
exposing the innards of a class's implementation to the outside
world just so you can unit-test it. The last point is something I
don't like about OOP + TDD in languages like C# or java and I
think D has (accidentally) solved this in a beautiful way, and I
would dislike to see this feature go.
