Property discussion wrap-up

[Rob T]

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?
>
>

Good point.

A property-struct could behave like a struct and also like a 
regular member function.

Member functions work because they take in a pointer to the 
struct or class when called, eg

a.b.foo();

becomes

a.b.foo(&a);

auto x = a.b; // returns property value of b, not b itself.
auto x = &a.b; // returns delegate pointer to b
x.foo(); // OK

--rt