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Date: Sun, 07 Jul 2002 22:27:00 -0000
From: Tim Hollebeek <tim@hollebeek.com>
To: Robert Dewar <dewar@gnat.com>
Cc: pkoning@equallogic.com, gcc@gcc.gnu.org, geoffk@geoffk.org,
        lars@nocrew.org
Subject: Re: Comparing doubles
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> <<Truncation before compare allows {a==b, b==c, c!=a}, and all other
> sorts of unreasonable things.  Regardless of whether the standard
> strictly requires it or not, it is reasonable to expect equality to be
> an equivalence operation.
> >>
> 
> But it is not necessarily the case that a==a (in the case of a NaN) so
> your equivalence relation does not cover NaN's. That's still reasonable,
> but it is worth noticing the exception.

I was going to mention it, but couldn't find a good way of saying
"when restricted to 'real' values."  Thanks.