Proposal: Faster conversion between Rational and Double/Float

[Henning Thielemann]

On Thu, 31 Mar 2011, Daniel Fischer wrote:

> Summary:
>
> I propose
> - adding modules implementing integer logarithm functions to integer-gmp
> and integer-simple
> - changing the implementation of toRational and fromRational for Double and
> Float using those to become significantly faster.

Is there also a rule to, say, convert
   fromRational . toRational :: Double -> Double
  to 'id'? Sure 'id' is not quite correct because of NaNs. Maybe 
'realToFrac'.