infinity comparison

David T. Lewis lewis at mail.msen.com
Sun Sep 19 20:08:55 UTC 2004


On Sun, Sep 19, 2004 at 07:27:03PM -0400, Lex Spoon wrote:
> 
> It does appear that we have to favor one semantics or the other.  [-1.0
> sqrt] has to evaluate either to [Complex i] or to [NaN], which in turn
> have to be different values.  Keystroke for keystroke, I'd guess that
> for Smalltalk, sloppy intuitive arithmetic, where you'd prefer [Complex
> i], is much more common than carefully tuned Floating point arithmetic,
> so I'd guess we want to make [-1.0 sqrt] be [Complex i].

How about:
  -1.0 sqrt ==> Complex i
  Complex i asFloat ==> NaN

Thus:
  -1.0 sqrt asFloat ==> NaN

Dave




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