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From: Andy Wingo <wingo@pobox.com>
To: Mark H Weaver <mhw@netris.org>
Cc: Taylor R Campbell <campbell@mumble.net>, guile-devel@gnu.org
Subject: Re: Equality predicates, signed zeroes, R5RS and R6RS
Date: Wed, 02 Feb 2011 21:09:10 +0100	[thread overview]
Message-ID: <m3wrlitd09.fsf@unquote.localdomain> (raw)
In-Reply-To: <87k4hkyhmu.fsf@yeeloong.netris.org> (Mark H. Weaver's message of "Mon, 31 Jan 2011 14:53:29 -0500")

On Mon 31 Jan 2011 20:53, Mark H Weaver <mhw@netris.org> writes:

> Given that everyone agrees that `eqv?' must distinguish 0 from 0.0, it
> is already not useful as a numerical `='.  Any program that uses it this
> way is asking for trouble.  Therefore, I don't have qualms about keeping
> our existing behavior, namely that (eqv? 0.0 -0.0) returns #f.
>
> What do you think?

This sounds OK to me.  I don't have a horse in the race, but the
argument that (eqv? 0 0.0) => #f is convincing, especially given the
0.0-or-0 games that many procedures are allowed to play.

Andy
-- 
http://wingolog.org/



  reply	other threads:[~2011-02-02 20:09 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20110131185050.9C10F98298@pluto.mumble.net>
2011-01-31 19:53 ` Equality predicates, signed zeroes, R5RS and R6RS Mark H Weaver
2011-02-02 20:09   ` Andy Wingo [this message]
2011-01-31 21:36 Mike Gran
2011-01-31 22:42 ` Mark H Weaver
  -- strict thread matches above, loose matches on Subject: below --
2011-01-31 23:13 Mike Gran

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