Property discussion wrap-up

[Zach the Mystic]

On Wednesday, 30 January 2013 at 18:36:17 UTC, Dmitry Olshansky 
wrote:
> I have one key problem - the hidden pointer detail.
> In other words how should it find the instance of the outer 
> struct to to access it?
>
> struct A{
> 	int a;
> 	struct B{
> 		void foo(){ a = 42; }
> 	}	
> 	B b;
> }
>
> A a;
> a.b.foo(); //how that b is supposed to know it's outer struct 
> without the hidden pointer?
>
> auto x = a.b;
> x.foo();// and now what?

It seems struct B does need a pointer... and yet it only needs it 
in compile time. "auto x = a.b" is no different from "alias a.b 
x", because when you have no data, you have no data to worry 
about! a.b is nothing but a namespace with full struct semantics.

I can only say that my intuition tells me that this is easily 
managed. I cannot tell you what adjustments need to be made to 
the compiler to get this to come out right.

But what if B actually had some data? The only solution is to 
have one pointer for every struct it's nested inside of. I can 
imagine it getting tricky in this case. If it were so tricky as 
to be prohibitive to implement, then all is not lost. You can 
still implement zero-data structs as properties. In that case, I 
suggest weaving the implementation in directly with the 
Highlanders, because Highlanders will be much less appealing for 
any other use.