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SubjectRe: macro conflict
Date
From: "Andrew Cannon" <ajc@gmx.net>
>
> What about this then:
>
> #define min(x,y) ({typeof(x) __x=(x); typeof(y) __y=(y); (__x < __y) ?
> __x : __y})
>
> This is guaranteed to work the same as the old min/max in all cases but
> without side effects. You can still force the comparison to be done with
> a certain type by casting the arguments first:
>
[snip]

Well it's closer but not really what i want.
The min/max_type is maybe the way to go, but the above can still bit you if
the types differ. Consider max().

char lut[256];
int c1 = 256+rand()%256;
char c2 = rand()%256;
char dest = lut[max(c2,c1)];

Won't c1 still be returned untruncated?

Ofcourse one will use another construct for these kinds of checks, but maybe
your brain collapses just for a second and think that this will return a
char.

OK ok bad example, but maybe you see that i have a point here somewhere
(under my chair? :) ).

Magnus

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Programmer/Networker [|] Magnus Naeslund
PGP Key: http://www.genline.nu/mag_pgp.txt
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