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From: rob@kaa.eng.ohio-state.edu (Rob Carriere)
Newsgroups: comp.lang.c
Subject: Re: Another silly question
Message-ID: <2206@quanta.eng.ohio-state.edu>
Date: 18 May 89 01:02:16 GMT
References: <17812@cup.portal.com> <2336@Portia.Stanford.EDU>
Sender: news@quanta.eng.ohio-state.edu
Reply-To: rob@kaa.eng.ohio-state.edu (Rob Carriere)
Organization: Ohio State Univ, College of Engineering
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In article <2336@Portia.Stanford.EDU> mesmo@Portia.Stanford.EDU (Chris Johnson)
writes:
>	The supposed proof of a[i] == i[a] rests on the faulty
>	assumption that (x+y) == (y+x) in all contexts; this is
>	not correct.

No it doesn't.  It relies on a direct statement in K&R I (pg 210, 1st par)

"Therefore, despite its asymmetric appearance, subscripting is a
commutative operation."

>	When "+" denotes simple (ie int/float/etc) arithmetic, the
>	operation commutes; when it denotes pointer arithmetic,
>	commutation is not legal/meaningful.

There is no such statement in K&R; in fact, the paragraph from the
above quote came implies the oppposite and so does the section on the
"+" operator (A7.4, pg188--189)

SR