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From: petrilli@walt.cc.utexas.edu (Chris Petrilli)
Newsgroups: comp.lang.c++
Subject: Re: #defines....
Message-ID: <33133@ut-emx.UUCP>
Date: 2 Jul 90 16:00:58 GMT
References: <37786@genrad.UUCP>
Sender: news@ut-emx.UUCP
Reply-To: petrilli@walt.cc.utexas.edu (Chris Petrilli)
Organization: The University of Texas at Austin, Austin, Texas
Lines: 34

In article <37786@genrad.UUCP> slp@genrad.genrad.COM (Steven L. Peters) writes:
>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...
>

The only time where you HAVE to use a #define (or at least, it is the best
way for clarity) is in conditionally compiled code.  For example:

#define DEBUG

#ifdef DEBUG
 ... (do something) ...
#endif

This would be more difficult under C++ convention of using constants, than
the preprocessor, since you don't care about type, just whether it is defined
or not.

Hope this clarifies it... if someone can thing of another time where you HAVE
to use the pre-processor, I'd like to know, I might be misusing/abusing 
C++.


+ Chris Petrilli                                    "Opinons represented here
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