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Re: C++



On Mon, 24 Feb 2003, Thomas Dodd wrote:

>  I had a question for a C++ programmer. Thought I might find one here :)
>
>
> I have 2 classes that need to reference each other.
>
> "headerA.h"

  class B; // Forward declaration of class B.

> class A{
> public:
>    int x;
>    int y;
>    B *left;
>    B *right;
> }
>
> "headerB.h"

  class A;  // Forward declaration of class A.

> class B{
> public:
>    int a;
>    int b;
>    A *parent;
>    char foo();
> }
>
> Give that top is of type A, in top.left.foo() I need to modify top.right.a
>
> Any ideas? I've tried passing a A* in the constructor for B, but the
> compiler doesn't
> realize that A is a class when I try to compile, and complains about no
> type listed.
>
> I seams to be a circular reference since A needs B and B needs A. This
> cannot be that
> unusual, and has probably been solved before, I just don't know how.
>
> Right now moy only though is to make parent a void* and the cast it to a
> A* in the
> implementation of B. That removes all type checking though and I'd
> rather not abuse
> void pointers like that.
>
>     -Thomas
>
>
>
>
>

-- 
		Matthew Saltzman

Clemson University Math Sciences
mjs clemson edu
http://www.math.clemson.edu/~mjs





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