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From: dsrekml@prism.gatech.EDU (Mike Mitten)
Newsgroups: comp.lang.c
Subject: Re: Computing the absolute value of an integer
Keywords: absolute, abs(), fabs()
Message-ID: <8977@hydra.gatech.EDU>
Date: 6 May 90 05:42:31 GMT
References: <11679@june.cs.washington.edu> <1990May4.121950.22726@agate.berkeley.edu>
Organization: Georgia Institute of Technology
Lines: 31

In article <1990May4.121950.22726@agate.berkeley.edu> c60c-3cf@e260-3c.berkeley.edu (Dan Kogai) writes:
>What's wrong with using a macro like the following
>
>#define abs(x) (((x) >= 0) ? (x) : -(x))

...

>	I just took a look at /usr/include/math.h and it was even more
>concice:
>
>#define _abs(x) (x < 0 ? (-x): (x))


Won't both of these macros blow up if x is a function such as:

	y = abs(foo(bar));

or

	y = _abs(foo(bar));


	Shalom,

	      -Mike
Mike  Mitten                              -- Irony is the spice of life. --
WREK Radio, Georgia Tech, Atlanta GA, 30332  (404) 894-2468
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