Path: utzoo!attcan!uunet!sco!seanf
From: seanf@sco.COM (Sean Fagan)
Newsgroups: comp.lang.c
Subject: Re: For vs while (was Re: Comparing strings...)
Message-ID: <8308@scolex.sco.COM>
Date: 20 Oct 90 09:18:39 GMT
References: <2205.271700c2@cc.nu.oz.au> <1990Oct13.190106.15615@ux1.cso.uiuc.edu> <10678.271ade27@amherst.bitnet> <1990Oct17.030157.460@ux1.cso.uiuc.edu> <2226@ukc>
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Reply-To: seanf (Sean Fagan)
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In article <2226@ukc> tlg@ukc.ac.uk (T.L.Goodwin) writes:
>Almost, but not quite.  If the body of the loop contains a "continue",
>then the second example becomes an infinite loop (other changes to i
>and "break"s notwithstanding), since the increment is never reached.

#define	while(cond)	for(;cond;)

(I'm sitting here trying to think of any case where this will break
[no pun intended 8-)] something; I can't think of any, offhand.)

If you have something such as

	while () {
		whatever;
	}

this will be an infinite loop given the macro, but a syntax error otherwise.
But that's all I can think of...

(I've wondered why C had while, because of this.  The only think I could
think of was that for came after while, and They didn't want to break
existing code...  Any commentators?  [Henry?  Chris?  Doug?  Dennis?])

-- 
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