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From: aka@cbrma.UUCP
Newsgroups: net.lang.c
Subject: Re: swap() macro
Message-ID: <4728@cbrma.UUCP>
Date: Mon, 7-Jul-86 14:37:02 EDT
Article-I.D.: cbrma.4728
Posted: Mon Jul  7 14:37:02 1986
Date-Received: Wed, 16-Jul-86 20:25:32 EDT
References: <1201@brl-smoke.ARPA> <193@stracs.cs.strath.ac.uk> <733@ho95e.UUCP> <1836@brl-smoke.ARPA> <2225@umcp-cs.UUCP>
Reply-To: aka@cbrma.UUCP (Andy Kashyap(Andy) x5292)
Organization: AT&T-BL, RMAS, Columbus
Lines: 50

In article <2225@umcp-cs.UUCP> chris@maryland.UUCP (Chris Torek) writes:
>In article <1836@brl-smoke.ARPA> gwyn@brl.arpa (Doug Gwyn
>(VLD/VMB) <gwyn>) writes:
>>It may be amusing and/or instructive to contemplate the fact that
>>there is no way to write a function that exchanges the contents of
>>two variables in a language where parameters are passed "by name".
>
>How so?  It seems rather simple.  I have here a C program that effects
>call-by-name and does indeed perform a swap:

[ ... fragmen
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