Nested Structs

[Steven Schveighoffer]

On Mon, 27 Dec 2010 08:54:37 -0500, d coder <dlang.coder at gmail.com> wrote:

> Greetings All
>
> I have a situation where I have a struct nested inside a class. I
> would like to make the enclosing class' members visible inside the
> nested struct's constructor. I see that such preposition is feasible
> for nested classes, but not for nested structs. Why so?

A struct nested in a class does not have a hidden "outer" pointer as a  
nested class does.  It's because a struct is generally more bare-bones  
than a class (which has loads of hidden pieces: vtable, interfaces,  
classinfo, etc.).  Also, instantiating such a struct does not tie it to a  
class instance.

>
> Are there some alternative constructs which could give me this
> behavior for nested constructs?

You need to implement this behavior on your own:

class C
{
   struct S
   {
     private C _outer;
     this(C c) { this._outer = c; _outer.x = 5;} // access enclosing class  
instance via _outer.
   }

   int x;
}

-Steve