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From: Daniel_Gregory_Corbett@cup.portal.com
Newsgroups: comp.lang.c++
Subject: Re: #defines....
Message-ID: <31369@cup.portal.com>
Date: 3 Jul 90 04:17:35 GMT
References: <37786@genrad.UUCP>
Organization: The Portal System (TM)
Lines: 25

Stephen Peters asks:
>Just out of curiousity...
>
>With the C++ const, enum, and inline declarations, is it ever
>necessary to use #define in a C++ program?  Stroustrup emphatically
>says in _The C++ Programming Language_ not to use them if you don't
>have to.  I'm wondering if you ever have to.  I can't think of a
>single time where you would be forced to use a #define over const or
>inline...

If you wish to use conditional compilation using #ifdef, and the like
then #defines are required.  const variables are not understood by cpp
and are therefore ignored.

Example:

#define DEBUG		/* This might be defined on the command line */
			/* using -DDEBUG */

#ifdef DEBUG
printf("Debug Statement i=%d\n", i);
#endifk


		- Daniel