Accessing outer class attribute from inner struct

[Andre Pany via Digitalmars-d-learn]

On Tuesday, 29 August 2017 at 08:30:24 UTC, Moritz Maxeiner wrote:
> On Tuesday, 29 August 2017 at 07:59:40 UTC, Andre Pany wrote:
>> On Monday, 28 August 2017 at 23:12:40 UTC, Moritz Maxeiner 
>> wrote:
>>>
>>> In both cases S doesn't inherently how about C, which means a 
>>> solution using default initialization is not feasible, as 
>>> S.init can't know about any particular instance of C.
>>> I don't think there's any way for you to avoid using a class 
>>> constructor.
>>
>> Thanks for the explanation. I now tried to use a class and use 
>> a static opIndex. But it seems from a static method you also 
>> cannot access the attributes of a outer class :)
>
> A nested class' outer property (when nested inside another 
> class) is a class reference, which means we not only require a 
> class instance of the outer class to reference, but also a 
> class instance of the nested class to store said class 
> reference to the other class in.
> A static class method (by definition) is invoked without a 
> class instance.
> The two are inherently incompatible.
>
>> [...]
>>
>> This seems like an unnecessary limitation...
>
> I can only recommend reading the language specification w.r.t, 
> nested classes [1] if it seems that way to you, because it is 
> not.
>
> [1] https://dlang.org/spec/class.html#nested

I think I found a solution which fulfills all goals but I have to 
try it out. A property method "Columns" will return an 
initialized struct "ColumnsArray" as proposed by you.
This should nicely work as string mixin. Thanks for your help.

Kind regards
André