[Haskell-cafe] Why is toRational a method of Real?

Henning Thielemann lemming at henning-thielemann.de
Thu Aug 5 05:24:29 EDT 2010

On Thu, 5 Aug 2010, Ivan Lazar Miljenovic wrote:

> On 5 August 2010 10:15, Lennart Augustsson <lennart at augustsson.net> wrote:
>> You're right.  It's bad to have toRational in Real.  It's also bad to
>> have Show and Eq as superclasses to Num.
> I understand why it's bad to have Show as a superclass, but why Eq?
> Because it stops you from using functions as numbers, etc. ?

Yes, and on lazy computable reals (==) is not defined for numbers that are 

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