forward declaration related problem

From: exits funnel (exitsfunnel_at_NOSPAMyahoo.com)
Date: 11/30/03 

Date: Sat, 29 Nov 2003 23:43:45 GMT

Hello,

I have the following code:

class A
{
   public:
     A(int i = 0):asInt(i) { }
     operator B( ) { return B(asInt); }
   private:
     int asInt;
};
class B
{
   public:
     B(int i = 0):bsInt(i) { }
     operator A( ) { return A(bsInt); }
   private:
     int bsInt;
};
int main( )
{ }

When I try to compile it my compiler has this to say:
> test.cpp:5: parse error before `('
> test.cpp:5: syntax error before `('
> test.cpp:7: semicolon missing after declaration of `A'
> test.cpp:7: parse error at null character
> test.cpp: In method `A::A (int)':
> test.cpp:4: class `A' does not have any field named `asInt'
> test.cpp: At top level:
> test.cpp:7: parse error at null character

The problem is obviously that when the compiler hits the reference to B
in A it doesn't yet know anything about A. So I add this:

class B;

to the very beginning of the file and now my compiler rebuts with:
> test.cpp: In method `A::operator B ()':
> test.cpp:7: return type `class B' is incomplete
> test.cpp:7: invalid use of undefined type `class B'
> test.cpp:1: forward declaration of `class B'

I understand the issue here, but I'm not sure how to solve it. If
anyone could point me in the right direction I'd really appreciate it.
Thanks in advance.

-exits

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