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
Lines:	35
Message-ID:	<34E829DA.56FBE8A8@alcyone.com>
References:	<6c99k6$1u6 AT bgtnsc02 DOT worldnet DOT att DOT net>
NNTP-Posting-Host:	165.90.20.242
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

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
                                     \
        "I've got the fever for the / flavor of a cracker"
                                   / Ice Cube

- Raw text -