From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Help with class "chicken or the egg" problem
Date: Mon, 16 Feb 1998 03:58:18 -0800
Organization: Alcyone Systems
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Riley wrote:

> I am having trouble writing a program.  Is there an equivalent to a
> function
> prototype but for classes???  I have two classes that have pointers to
> each
> other and I can't figure out how to define them.  Attached is a simple
> demonstration program to get my point across.

Particularly in your case, the solution is very simple:  Simply declare
the other class before you define the new one.  If there are only
pointers involved, then you will never have a problem.  This is, by the
way, exactly analogous to the situation in C where you have opaque
pointers to structures, where the compiler never learns about the
internal makeup of those structures, but doesn't have to care:

    class B;

    class A
    {
      private:
        B *b;

        ...
    };

    class B ...

-- 
         Erik Max Francis, &tSftDotIotE / mailto:max AT alcyone DOT com
                       Alcyone Systems / http://www.alcyone.com/max/
  San Jose, California, United States / icbm://+37.20.07/-121.53.38
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