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From: brianj@witsend.cs.umd.edu (Brian Johnson)
Newsgroups: comp.sys.mac.programmer
Subject: Circular Referencing Think C Classes
Message-ID: <BRIANJ.90Sep5175658@witsend.cs.umd.edu>
Date: 5 Sep 90 21:56:58 GMT
Sender: news@mimsy.umd.edu
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Organization: University of Maryland Computer Science
Lines: 52


What do I need to do in order to let two classes "talk" to each other.
It took me awhile to figure out that this was my problem.  Is there
some sort of forward declaration for classes (class structs)
referenced in this way.

Here are four sample files.
Example Code:

#define	_H_Class1			/* Include this file only once */
#include "Class3.h"

struct Class1 : indirect {
	Class3	*three;
	void doit(void);
};

---------------------

#include "Class1.h"
#include <Stdio.h>

void	Class1::doit(void) {
	printf("I'm Class One.");
}

---------------------

#define	_H_Class3			/* Include this file only once */
#include "Class1.h"			

struct Class3 : indirect {
	Class1	*one;		
	void doit(void);
};

---------------------

#include "Class1.h"
#include <Stdio.h>

void	Class3::doit(void) {
	printf("I'm Class Three.");
}

Thanks,


--
Brian Johnson          Computer Science Department 
brianj@cs.umd.edu      University of Maryland  
(301) 405-2725         College Park, Md 20742