In article <90nr64$45i$1@nnrp1.deja.com>, Rene Nyffenegger wrote:

> I am getting stuck with
>
>
> class A {
>   B _b;
> };
>
> class B {
>   std::vector<A> GetSomeAs();
> };
>
> I cant't think of way using forward declarations to solve that!
> If someone can, please let me know.

If your compiler doesn't accept this, then forward-declare class B
before class A, and declare _b to be a pointer to a B.

However, I *think* it should be possible to get what you're after by
writing:

  #include <vector>

  class A;

  class B {
    std::vector<A> GetSomeAs();
  };

  class A {
    B _b;
  };

In fact, it would be very useful to be able to declare recursive data
structures like:

#include <vector>

struct Node {
  int data;
  std::vector <Node> children;
};

CORBA IDL allows something like this; I'm not sure the C++ standard
allows it too.  Anyone?  [cross-posted to comp.std.c++]

- Wil

--
Wil Evers, DOOSYS IT Consultants, Maarssen, Holland
[Wil underscore Evers at doosys dot com]

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