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From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr)
Newsgroups: comp.lang.c
Subject: Re: Type-independent absolute value
Keywords: abs, labs
Message-ID: <799@crdos1.crd.ge.COM>
Date: 4 Oct 89 18:18:45 GMT
References: <1389@cipc1.Dayton.NCR.COM>
Reply-To: davidsen@crdos1.UUCP (bill davidsen)
Organization: GE Corp R&D Center
Lines: 20

In article <1389@cipc1.Dayton.NCR.COM>,
	gmaranca@cipc1.Dayton.NCR.COM (Gabriel Maranca) writes:
|	[ she uses... ]
|  #define ABS(x) (((long)(x) < 0L)? -(x) : (x))

|	[ and asks... ]
|  Is this non-ANSI or unportable? It works for me.

  I don't see anything which is non-portable code, but have a few
suggestions:
	1. instead of -(x) use (-(x)).
	2. you might want to use (double) to work with more types
	3. you still have to be careful about what you use for an
	   argument to avoid things like ABS(x[m++]) which are only
	   evaluated once if ABS is a procedure.
-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon