[racket] Typed Racket Performance Optimization

From: Hendrik Boom (hendrik at topoi.pooq.com)
Date: Thu May 10 09:43:27 EDT 2012

On Thu, May 10, 2012 at 08:55:06AM -0400, Ray Racine wrote:
> It was late... but the penny dropped this morning.   Consider the domain of
> log (x) for x<0.

Where log a multivalued function, and none of the values are real.

Acually, the logarithm function complex numbers is multivalued even 
when the argument happens to be real.  A good example of how functions 
need to be inherently typed, even when there are more-or-less 
compatible versoins for different types.

You get similar, bit simpler, behaviour with square root.

-- hendrik

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