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From: James Kuyper <kuyper@wizard.net>
Subject: Re: Multiple declarations in for loop?
Date: 1998/05/26
Message-ID: <356A4155.2781@wizard.net>#1/1
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Approved: stephen.clamage@sun.com (comp.std.c++)
References: <356196A0.4214@lehman.com> <6jsdc4$fvr@engnews1.Eng.Sun.COM> <6jutcg$96n@marianna.psu.edu>
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Oleg Zabluda wrote:
> 
> Steve Clamage <clamage@Eng.Sun.COM> wrote:
> : In article 4214@lehman.com, Cristian Georgescu <cgeorges@lehman.com> writes:
> : >> Only one simple-declaration is allowed. The following declares i and j as
> : >> you wish
> : >> for (int i=0, j=0; i<10,j<10; i++, j++) ...
> : >
> : >Is there a reason for this limitation (only one simple declaration);
> : >why not:
> : >
> : > for (int i=0, unsigned int j=0; i<10,j<10; i++, j++) ...
> 
> : You can't write
> :       int i=0, unsigned int j=0;
> : in any context, so it would be odd to allow it in a for-loop header.
> : The comma in a declaration separates declarators, it doesn't end
> : a declaration.
> 
> It would be odd, but I think it would be worth it, because
> it is frequently needed, and the alternatives are pretty
> ugly. If the goal is to reduce oddity, maybe allowing
> it in all other relevant contexts would be a solution :-) ?
> Unless it would break something else, of course.

I don't think that the following is very ugly, just a little clumsy:

{
	unsigned int j;
	for(int i=0; i<10 && /* Note correction */ j<10; i++, j++)
	{
		// Loop body; which presumably changes i or j, but not
		// always in the same way; otherwise j is redundant.
	}
}


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