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From: rhg@cpsolv.CPS.COM (Richard H. Gumpertz)
Newsgroups: comp.lang.c
Subject: Re: Is this swap() macro correct?
Message-ID: <486@cpsolv.CPS.COM>
Date: 18 Jan 90 23:18:13 GMT
References: <21068@stealth.acf.nyu.edu>
Reply-To: rhg@cpsolv.uucp (Richard H. Gumpertz)
Distribution: usa
Organization: Computer Problem Solving, Leawood, Kansas
Lines: 19

In article <21068@stealth.acf.nyu.edu> brnstnd@stealth.acf.nyu.edu (Dan Bernstein) writes:
>Say swap() is defined as
>
>#define block do {
>#define endblock } while(0)
>#define swap(x,y,typ) block typ *_MV_x = x; typ *_MV_y = y; typ tmp;\
>                    tmp = *_MV_x; *_MV_x = *_MV_y; *_MV_y = tmp; endblock
>
>Now constructions like swap(f++,g++,real) work and are faster than a

Stylistic nit: I would make it &(x) and &(y) in the first line of swap and
make typ the first parameter and then make the call you show be
	swap(real, *f++, *g++)
Maybe I am strange, but I find that easier to read.
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