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From: Alfred Perlstein <bright@mu.org>
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To: Lawrence Stewart <lstewart@freebsd.org>
Subject: Re: Adding a FOREACH_CONTINUE() variant to queue(3)
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On 4/30/13 8:57 PM, Lawrence Stewart wrote:
> [reposting from freebsd-arch@ - was probably the wrong list]
>
> Hi all,
>
> I've had use for these a few times now when wanting to restart a loop at
> a previously found element, and wonder if there are any thoughts about
> sticking them (and equivalents for other list types) in <sys/queue.h>?
>
> Cheers,
> Lawrence
>
> #define TAILQ_FOREACH_CONTINUE(var, head, field)		\
> 	for ((var) = ((var) ? (var) : TAILQ_FIRST((head)));	\
> 	(var);							\
> 	(var) = TAILQ_NEXT((var), field))
>
>
> #define SLIST_FOREACH_CONTINUE(var, head, field)		\
> 	for ((var) = ((var) ? (var) : SLIST_FIRST((head)));	\
> 	(var);							\
> 	(var) = SLIST_NEXT((var), field))
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>

Can you show a few uses please?  If it can significantly cut down on 
extra code it seems wise.

-Alfred