wren ng thornton
wren at freegeek.org
Sat Aug 27 03:00:25 CEST 2011
On 8/26/11 7:24 PM, Daniel Fischer wrote:
> Using that as intermediate type instead of Rational in realToFrac would
> allow a correct Double<-> Float (and newtypes) conversion also without
> rewrite rules (and should be faster than 'fromRational . toRational' for
> these, since it would be basically 'uncurry encodeFloat . decodeFloat').
For these issues I'd like to point out the RealToFrac class for
correcting the problems with the Prelude's realToFrac. The current
version uses -XOverlappingInstances to provide general instances, but
that's just a convenience and not strictly necessary. The only thing it
actually requires is MPTCs. I've been waiting for the haskell' committee
to finally get around to accepting MPTCs before suggesting the class
replace the Prelude's function.
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