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Re: reading NaNs



Aubrey Jaffer wrote:
 | Date: Mon, 24 Oct 2005 03:25:09 -0500
 | From: Alan Watson <a.watson@xxxxxxxxxxxxxxxx>
| | NaNs are atoms -- they have no context or stucture, just a single
 | value.

In an implementation which boxes flonums, NaNs aren't a single value;
EQ? and EQV? are *not* guaranteed to return #t given two NaNs.

eq? is not guaranteed to return #t given two equal flonums
eqv? *is* guaranteed to return #t given two equal flonums.

NaNs should be the same: two NaNs that have the same bit-pattern
and size must compare as eqv? but not necessarily eq?.
--
	--Per Bothner
per@xxxxxxxxxxx   http://per.bothner.com/