Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!bionet!sdsu!usc!elroy.jpl.nasa.gov!cit-vax!wen-king
From: wen-king@cit-vax.Caltech.Edu (King Su)
Newsgroups: comp.lang.c
Subject: Re: comma operator
Message-ID: <11445@cit-vax.Caltech.Edu>
Date: 2 Aug 89 03:36:55 GMT
References: <10099@mpx2.mpx.com> <93@microsoft.UUCP> <10100@mpx2.mpx.com> <10562@smoke.BRL.MIL> <1989Jul24.194646.3012@nc386.uucp> <5630@pt.cs.cmu.edu> <1989Jul28.174033.12734@jarvis.csri.toronto.edu> <3553@buengc.BU.EDU>
Reply-To: wen-king@cit-vax.UUCP (Wen-King Su)
Organization: California Institute of Technology
Lines: 29

In article <3553@buengc.BU.EDU> bph@buengc.bu.edu (Blair P. Houghton) writes:
>In article <1989Jul28.174033.12734@jarvis.csri.toronto.edu> flaps@dgp.toronto.edu (Alan J Rosenthal) writes:
<>
>>dandb@k.gp.cs.cmu.edu (Dean Rubine) writes:
<>>I also occasionally use the comma to save braces:
>>>	if((f = fopen(file, "r")) == NULL)
<>>		fprintf(stderr, "Can't open %s\n", file), exit(2);
>>
<>Funny, I use braces to save commas:
>>	if ((f = fopen(file, "r")) == NULL) {
<>		fprintf(stderr, "Can't open %s\n", file);
>>		exit(2);
<>	}
>
<Funny, you didn't notice the syntactic error of putting a statement
>as the comma's operand, which may only be an expression...

Funny, you didn't notice that both fprintf(...) and exit(...) are
expressions.

My rule about style is that there is no rule.  You can use NULL, TRUE,
comma, or even goto, as long as the end product is easier to understand
as a result of their use.  You can even change your style from time to
time, if it helps.

-- 
/*------------------------------------------------------------------------*\
| Wen-King Su  wen-king@vlsi.caltech.edu  Caltech Corp of Cosmic Engineers |
\*------------------------------------------------------------------------*/