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From: jik@athena.mit.edu (Jonathan I. Kamens)
Newsgroups: comp.lang.c
Subject: Re: #define DEBUG... (using printf for debugging)
Message-ID: <1990May3.234339.6582@athena.mit.edu>
Date: 3 May 90 23:43:39 GMT
References: <1717@engage.enet.dec.com>
Sender: news@athena.mit.edu (News system)
Reply-To: jik@athena.mit.edu (Jonathan I. Kamens)
Organization: Massachusetts Institute of Technology
Lines: 39

In article <1717@engage.enet.dec.com>, wallace@oldtmr.enet.dec.com (Ray
Wallace) 
writes:
|> Why not just do this -
|> 
|> #define	BITCH				/* IE: don't print it */
|> #define	DEBUG printf			/* IE: do print it */
|> main( )
|> {
|>   BITCH( "What the <%s> is going on?\n", "hell" );
|>   DEBUG( "%d - nothing.\n%d - something.\n", 1, 2 );
|> }

  Because it's sloppy and causes good compilers to complain.  Compiling
your program on an IBM RT/PC running AOS4.3 with MetaWare's High C
compiler (version 2.1y) works, but produces the following warnings:

    w "foo.c",L5/C8:        "What the <%s> is going on?\n"
    |    Expression has no side-effects.
    w "foo.c",L5/C8:        Expression has no side-effects.

It's stupid to write code that makes the compiler bitch when it's
possible to accomplish the same purpose without the compiler complaining
at all.  The more a compiler is forced to bitch, the more programmers
come to expect compiler error messages, and therefore the less seriously
they take them.

  I personally make it a policy never to write any "real" code (i.e.
code that I expect anyone else to ever see; and please let's not get
into the debate of one-time-only programs again) that won't compile with
High C without any errors.  I wish more programmers had better compilers
to check their code with, and/or ran their code through lint more often,
because it's a rare program I get off the net that doesn't cause
compiler errors or warnings when I compiler it on my system.

Jonathan Kamens			              USnail:
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