[r6rs-discuss] Re: [Formal] eq?/eqv? misbehave around NaNs

Marcin 'Qrczak' Kowalczyk qrczak at knm.org.pl
Mon Nov 27 17:08:12 EST 2006


Alan Watson <alan at alan-watson.org> writes:

> An implementor could implement eqv? on singles or doubles either as a
> bitwise comparison (which would make NaNs with different bit patterns
> not eqv?) or with something like:
>
>    (or (and (nan? x) (nan? y))
>        (= x y))

Almost. The other special case is (= 0.0 -0.0) but (not (eqv? 0.0 -0.0)).

-- 
   __("<         Marcin Kowalczyk
   \__/       qrczak at knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/



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