comma operator

[Steven Kilbane]

>From article <2963 at solo6.cs.vu.nl>, by roemer at cs.vu.nl (Roemer Lievaart):
> tada at athena.mit.edu (Michael Zehr) writes:
> I often write:
> 
> 	if (something_goes(wrong) )
> 		fprintf(stderr, "%s: I give up!\n", argv[0] ) ,
> 		exit(2) ;
> 
> Of course it's no better than using { ; }, but it's not worse either.

Personally, I think it is worse that {;}. If you have something of the form

	x = Expr1 , Expr2;

then Expr2 will be assigned to x, rather than Expr1. If you rewrite them as

	x = Expr1,
	    Expr2;

you're relying on (a) the indentation and (b) being very careful, to notice you
have a comma instead of a semicolon. Inserting extra code might be nasty:

	x= Expr1,
	   Expr3;
	   Expr2;

*BOOM*...
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Stephen Kilbane                      |Email: skilbane at uk.co.bt.axion
British Telecom Research Laboratories|or smk-a at uk.ac.york.minster (or, if that
Martlesham Heath                     |doesn't work, root at uk.ac.york.softeng - 
Ipswich IP5 7RE (0473 646638)        |not me, but it may be passed on....
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